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Choosing the Right Interconnect Solution for Your Application

Posted By Paul Carter, Saturday, July 01, 2006
Updated: Sunday, February 10, 2013

The world’s population, although greater than ever, is also more connected than ever. We are linked by satellite, Internet, fiber optic cables, and high tech communication cords. We transmit data and power in fractions of seconds, often not giving a moment’s thought about the sophisticated technologies that allow these transmissions to take place.

Many of the devices that keep us connected rely on advanced interconnectivity solutions—connections designed to ensure that cable products deliver the most reliable and consistent data and power transfer. The industries that rely on advanced interconnect solutions are almost endless in their variety and number.

With so many potential applications, and different types of interconnect solutions available, how do you know where to turn? What are the parameters that you should consider when you are selecting an interconnectivity product provider?

In the current marketplace, technology can be the differentiator in supplier selection. If your requirements fall into the commodity category, then price and off-the-shelf availability are typically the prime factors in supplier selection. If your needs are simple, there are thousands of potential suppliers who can meet those needs. If your application has specific requirements related to data rates, custom cable design, high flex assembly designs and over molding, the field of potential suppliers narrows significantly.

Entering the world of custom interconnect solutions requires a detailed analysis to find the right supplier capable of cost effectively filling your requirements. There are many companies that produce both commodity and custom cable, but do not possess the capability to provide cable assemblies. Other companies purchase the cable from these suppliers, providing the assembly services which sometimes include over molding. These companies fill the niche of low technology interconnect solutions where applications are typically not performance driven.

Custom design and manufacturing

Custom high performance applications require the expertise of a fully integrated engineering driven company, possessing the ability to produce both cable and cable assemblies, along with the technical expertise to design and produce custom over molds. Suppliers in this marketplace may differentiate into high speed interfaces such as high speed coax, SCSI (small computer system interface), or Infiniband technologies typically used for enterprise computer applications. Of primary concern, for these applications is the need to maintain as low a dielectric constant as possible, while providing improved signal performance at high frequencies with performance measured according to differential impedance and skew.

As electronics packaging has become lighter and more portable a distinct need has developed for highly flexible cable, coiled cords and custom over molds. Specific design requirements must be achieved to yield a highly flexible yet durable product. Selection of conductor material, strand count, primary jacket compound, shielding and overall jacket each play a critical role in product performance. These materials must all work as a complete system, requiring that product design consider lay length and direction, jacket wall thickness and a number of other considerations in order to optimize performance.

Custom assembly

It is not just the material selection, but the parameters used in manufacturing that impacts results. The cable must be married to a connector system, with subsequent strength added, through the development of an appropriate over mold utilizing specific materials to enhance performance. To achieve these results requires a vertically integrated interconnect supplier having cable, cable assembly and over molding expertise.

Today’s technology driven companies need cable systems (integration of cable, over mold and assembly expertise), rather than mere cable assemblies, to achieve the desired results. Selection of a supplier with the core competence to meet your needs is a key ingredient for success. OEM’s sometimes move business to the lowest bidder, only to find out later that they received what they paid for (typically very little), and they are forced to deal with customer complaints driven by field failures.

Custom over mold

High performance over mold design is the lynch pin between the cable and connector system. Design considerations include application mobility, operating temperature, mechanical requirements and compound compatibility with jacket materials, all playing a key role in the success of the overall system. Shielded assemblies require special consideration to ensure that the shield remains contiguous throughout the mold.

Over molding can also provide environmental protection to the mated pair through the designed introduction of an interfacial moisture sealing ring. The seal rings inhibit the migration of moisture into the connector system, moisture that can affect the signal integrity and enhance corrosion. Over mold systems can also provide protection to the cable and equipment through development of systems that de-mate at designed pull strength. If excessive force is put on the cable, it will simply unplug rather than incurring the damages that usually result from a positive mating system.

Sophisticated product requirements demand specific company expertise to achieve cost-effective design solutions. Very low volume, high performance applications are typically manufactured in the United States; however, medium and high volume markets require companies with ready access to lower labor rates, typically found in Asia or Mexico. Companies with these capabilities are able to support your product through the entire product life cycle from design through full production, providing cost effective product from a consistent technology base.

As the world increasingly focuses on improving the environment, many government initiatives have been launched that are having sweeping impacts on industry. Today’s environmental directives, such as restriction of hazardous substances (RoHS) and waste electrical and electronic equipment (WEEE) are driving the industry to seek acceptable alternatives to restricted substances, while maintaining product performance for electronic applications. The ability to meet performance requirements and still achieve these environmental objects poses a great challenge for interconnect systems—particularly for highly mobile applications. The use of environmentally friendly solders and appropriate alternate alloy constructions is critical to compliance. An interconnect suppliers’ ability to perform a complete range of mechanical testing, including flex and extension testing, is imperative to qualify alternate designs.

Contract manufacturing

Ease of supply chain management should be considered as part of the selection process as well. Interconnect suppliers that can support Kanban and EDI order replenishment systems ensure proper management of product inventory. Order replenishment support ensures timely product delivery while significantly reducing inventory and the cost of order processing.

Electro-mechanical contract manufacturing is another key offering to look for when choosing an interconnect solutions provider. The ability to support contract manufacturing provides additional benefits in the area of cost and supply chain management. Low-cost manufacturing centers significantly lower overall manufacturing costs, ensuring a market-competitive end product.

Regardless of your industry, there are certain specific product design parameters, and possibly a number of stringent environmental regulations to comply with. Nearly every industry—from medical to military to telecommunications—relies on advanced interconnect solutions everyday. There are four key capabilities that should be strongly considered as constants in your selection process: custom design and manufacturing, custom assembly, contract manufacturing and custom over mold. In today’s increasingly competitive marketplace selection of an appropriate interconnect supplier capable of meeting all your interconnect needs is more important than ever.


 About Paul Carter: Paul Carter is vice president of sales and marketing for Whitney Blake Company, a leading interconnect solutions provider. The company's core areas of expertise include: custom cable design and manufacturing; custom cable assemblies; cord assemblies for "hi-flex" applications and custom over mold design and development. For more information please call 1-800-323-0479 or visit www.whitneyblake.com.

Tags:  Featured  July-August 2006 

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Choosing the Right Interconnect Solution for Your Application

Posted By Paul Carter, Saturday, July 01, 2006
Updated: Sunday, February 10, 2013

The world’s population, although greater than ever, is also more connected than ever. We are linked by satellite, Internet, fiber optic cables, and high tech communication cords. We transmit data and power in fractions of seconds, often not giving a moment’s thought about the sophisticated technologies that allow these transmissions to take place.

Many of the devices that keep us connected rely on advanced interconnectivity solutions—connections designed to ensure that cable products deliver the most reliable and consistent data and power transfer. The industries that rely on advanced interconnect solutions are almost endless in their variety and number.

With so many potential applications, and different types of interconnect solutions available, how do you know where to turn? What are the parameters that you should consider when you are selecting an interconnectivity product provider?

In the current marketplace, technology can be the differentiator in supplier selection. If your requirements fall into the commodity category, then price and off-the-shelf availability are typically the prime factors in supplier selection. If your needs are simple, there are thousands of potential suppliers who can meet those needs. If your application has specific requirements related to data rates, custom cable design, high flex assembly designs and over molding, the field of potential suppliers narrows significantly.

Entering the world of custom interconnect solutions requires a detailed analysis to find the right supplier capable of cost effectively filling your requirements. There are many companies that produce both commodity and custom cable, but do not possess the capability to provide cable assemblies. Other companies purchase the cable from these suppliers, providing the assembly services which sometimes include over molding. These companies fill the niche of low technology interconnect solutions where applications are typically not performance driven.

Custom design and manufacturing

Custom high performance applications require the expertise of a fully integrated engineering driven company, possessing the ability to produce both cable and cable assemblies, along with the technical expertise to design and produce custom over molds. Suppliers in this marketplace may differentiate into high speed interfaces such as high speed coax, SCSI (small computer system interface), or Infiniband technologies typically used for enterprise computer applications. Of primary concern, for these applications is the need to maintain as low a dielectric constant as possible, while providing improved signal performance at high frequencies with performance measured according to differential impedance and skew.

As electronics packaging has become lighter and more portable a distinct need has developed for highly flexible cable, coiled cords and custom over molds. Specific design requirements must be achieved to yield a highly flexible yet durable product. Selection of conductor material, strand count, primary jacket compound, shielding and overall jacket each play a critical role in product performance. These materials must all work as a complete system, requiring that product design consider lay length and direction, jacket wall thickness and a number of other considerations in order to optimize performance.

Custom assembly

It is not just the material selection, but the parameters used in manufacturing that impacts results. The cable must be married to a connector system, with subsequent strength added, through the development of an appropriate over mold utilizing specific materials to enhance performance. To achieve these results requires a vertically integrated interconnect supplier having cable, cable assembly and over molding expertise.

Today’s technology driven companies need cable systems (integration of cable, over mold and assembly expertise), rather than mere cable assemblies, to achieve the desired results. Selection of a supplier with the core competence to meet your needs is a key ingredient for success. OEM’s sometimes move business to the lowest bidder, only to find out later that they received what they paid for (typically very little), and they are forced to deal with customer complaints driven by field failures.

Custom over mold

High performance over mold design is the lynch pin between the cable and connector system. Design considerations include application mobility, operating temperature, mechanical requirements and compound compatibility with jacket materials, all playing a key role in the success of the overall system. Shielded assemblies require special consideration to ensure that the shield remains contiguous throughout the mold.

Over molding can also provide environmental protection to the mated pair through the designed introduction of an interfacial moisture sealing ring. The seal rings inhibit the migration of moisture into the connector system, moisture that can affect the signal integrity and enhance corrosion. Over mold systems can also provide protection to the cable and equipment through development of systems that de-mate at designed pull strength. If excessive force is put on the cable, it will simply unplug rather than incurring the damages that usually result from a positive mating system.

Sophisticated product requirements demand specific company expertise to achieve cost-effective design solutions. Very low volume, high performance applications are typically manufactured in the United States; however, medium and high volume markets require companies with ready access to lower labor rates, typically found in Asia or Mexico. Companies with these capabilities are able to support your product through the entire product life cycle from design through full production, providing cost effective product from a consistent technology base.

As the world increasingly focuses on improving the environment, many government initiatives have been launched that are having sweeping impacts on industry. Today’s environmental directives, such as restriction of hazardous substances (RoHS) and waste electrical and electronic equipment (WEEE) are driving the industry to seek acceptable alternatives to restricted substances, while maintaining product performance for electronic applications. The ability to meet performance requirements and still achieve these environmental objects poses a great challenge for interconnect systems—particularly for highly mobile applications. The use of environmentally friendly solders and appropriate alternate alloy constructions is critical to compliance. An interconnect suppliers’ ability to perform a complete range of mechanical testing, including flex and extension testing, is imperative to qualify alternate designs.

Contract manufacturing

Ease of supply chain management should be considered as part of the selection process as well. Interconnect suppliers that can support Kanban and EDI order replenishment systems ensure proper management of product inventory. Order replenishment support ensures timely product delivery while significantly reducing inventory and the cost of order processing.

Electro-mechanical contract manufacturing is another key offering to look for when choosing an interconnect solutions provider. The ability to support contract manufacturing provides additional benefits in the area of cost and supply chain management. Low-cost manufacturing centers significantly lower overall manufacturing costs, ensuring a market-competitive end product.

Regardless of your industry, there are certain specific product design parameters, and possibly a number of stringent environmental regulations to comply with. Nearly every industry—from medical to military to telecommunications—relies on advanced interconnect solutions everyday. There are four key capabilities that should be strongly considered as constants in your selection process: custom design and manufacturing, custom assembly, contract manufacturing and custom over mold. In today’s increasingly competitive marketplace selection of an appropriate interconnect supplier capable of meeting all your interconnect needs is more important than ever.


Read more by Paul Carter

Tags:  Featured  July-August 2006 

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Buyers Beware: Electrical Instrumentation for Use in Hazardous Locations

Posted By Robert (Bob) Baker, Saturday, July 01, 2006
Updated: Sunday, February 10, 2013

Buyers of salvaged, remanufactured, refurbished or new surplus electrical instrumentation for use in hazardous locations (including chemical process plants, refineries, and other industries/applications which are classified as hazardous) need to exercise caution in their instrumentation purchases. Doing so is especially important given the increased market for these items, which experts estimate at $100 million for the process industry and growing. There are several factors responsible for the rapid growth in this market: industry pressure for cost containment (maintenance budgets and small, local capital projects), increased overseas competition and the ongoing closure of North American chemical and hydrocarbon processing facilities.

Photo 1

Len Frier’s May/June 2002 IAEI News article noting that "beauty is only skin deep” could not be more appropriate when dealing with the above types of resold electrical instrumentation,1 especially when those instruments are to be used in hazardous (classified) locations as defined by the National Electric Code2 and the Canadian Electrical Code 3 with regulatory requirements such as Occupational Safety and Health Administration (OSHA) 1910.307. 4 This article is one way of generating process industry awareness of the potential safety risk posed by this instrumentation as well as the risk of regulatory non-conformance. By better understanding how salvaged, remanufactured, refurbished and new surplus electrical instrumentation is certified, buyers can better ensure that their safety management programs meet their needs, helping to provide safer work environments.


Photo 2

There is little process industry awareness of the fact that some nationally recognized testing laboratory (NRTL) instrument certifications may no longer comply with the defined standards to which they were originally certified. Such instruments include salvaged, remanufactured, refurbished or re-marketed as new surplus, even though the reselling entity leaves the original manufacturer’s nameplate containing an NRTL approval mark on the instrument. To date, buyers and installers have assumed that they have purchased replacement-in-kind instruments when, unfortunately, they may not be replacement-in-kind. These purchases require increased scrutiny, including management of change (MOC) evaluations, to better ensure that plant design standards and regulatory requirements are met.

This article will outline steps buyers can take to ensure that their salvaged, remanufactured, refurbished or new surplus electrical instrumentation meets requirements for use in hazardous (classified) locations. Before delving into these solutions, it is important to clarify some definitions.

Definitions

Reconditioned refers to any form of salvaged, refurbished, or remanufactured instrumentation. Transfer of instrument ownership has typically taken place during a reconditioning process with limited, if any, traceability associated with the instrument’s prior application, environmental conditions, handling, maintenance history, use of OEM parts during repairs, etc.

New Surplusis defined as unused current or obsolete instrumentation, which:

  • May or may not still be in the original packaging
  • May have been in end user, distributor or other intermediary inventory since original manufacture
  • May have been previously installed, calibrated and subsequently removed and repackaged without actually being started up.
  • May have had multiple ownership transfers without the instrument ever having been used

More traceability typically exists for new surplus instrumentation than for reconditioned instrumentation, but it is still usually limited. With new surplus instruments subjected to the scenarios outlined in the bullets above, the opportunity exists for unknown changes or hidden damage over the typically lengthy time and handling between original manufacture and subsequent resale.

Product Certification


Photo 3

OSHA safety standards contain requirements for "approval” (i.e., testing and certification) of certain products by a NRTL. These safety standards are found in Title 29 of the Code of Federal Regulations (29 CFR), and the provisions for NRTL certification are generally in Part 1910 (29 CFR Part 1910).4

OSHA recognition of an NRTL is an acknowledgement that the organization has the necessary qualifications to perform safety testing and can "properly certify” the specific products covered within its scope of recognition.4

Properly certified generally means:4

1. The product is labeled or marked with the registered certification mark of the NRTL.
2. The NRTL issues the certification for a product covered within the scope of a test standard for which OSHA has recognized it.
3. The NRTL issues the certification from one of its sites (i.e., locations) that OSHA has recognized.

NRTL Certification Positions

Of the NRTLs OSHA recognizes for the testing and certifying of instrumentation for use in hazardous (classified) locations, FM Approvals, LLC, a member of the FM Global Group has, to date, established its formal position regarding their approval certification mark for refurbished or new surplus product.

"It is FM Approvals’ position that only the original manufacturer of the approved product or an FM Approved remanufacturer whose facilities are part of the FM Approvals follow-up audit program, can remanufacture a product and reissue the FM Approvals certification mark. Any suggestion, practice or inference to the contrary is wrong and must cease.”

Further: "Any salvaged, remanufactured or new surplus electrical instrument cannot be labeled or relabeled as FM Approved for use in a classified hazardous location unless the refurbishing/new surplus supplier entity is audited and approved by FM Approvals, LLC, for that specific type of instrument.”

"Absent the above being met, the device can carry the FM Approvals certification only if the product has been resubmitted and approval granted by FM Approvals. Failure to follow these guidelines will invalidate the FM Approvals certifications. In such instances the FM Approvals certification mark shall be permanently removed from the product (including the nameplate).” 5


Photo 4

To date, the above position has not been well understood, especially in industries having plant/process unit areas classified as hazardous due to the potential presence of ignitable or combustible chemicals, hydrocarbons or dust, as defined by NEC,2 CEC,3 et al.

The typical perception is that an electrical/electronic instrument, once NRTL approved at the factory, remains NRTL approved for the life of the device. This perception is a major concern and results from the original equipment manufacturer (OEM) nameplate usually being left on reconditioned or new surplus instruments by a supplier which may not be audited or approved by the NRTL to do so. This is typically the situation even though there may be other non-OEM markings identifying the instruments as having been reconditioned. See example photo comparisons below.

Thus, both suppliers and purchasers may incorrectly perceive that reconditioned instruments meet engineering or maintenance specifications that require NRTL approval to sustain plant design standards and to comply with regulatory safety requirements. The FM Approvals position is clear that such is not the case; i.e, instruments are no longer approved, and its NRTL approval labeling should be removed. Without NRTL certification, these devices are no longer approved as safe for use in hazardous (classified) locations, thus presumably increasing the risk of a catastrophic accident. A management of change (MOC) evaluation would be necessary if these devices were considered for use in a location classified as hazardous.

Although the use of non-approved instrumentation may not yet have resulted in a catastrophic, explosive incident to date, it may be naïve to assume an accident will not happen in the future.

Typically, safety experts have embraced the philosophy that "just because there hasn’t been an accident in the past does not mean that the combination of situations required to cause an accident will not occur in the future.” However, in addition to the safety issue, the potential regulatory non‑compliance certainly creates additional financial exposure should an incident occur, especially if the incident involves personal injury or death.

Solutions

Within a process safety management program (PSM), including process hazard analysis (PHA), emphasis is needed to ensure hazard identification; adequate risk assessments; detailed attention to instrument specifications by engineering, purchasing and maintenance; supplier qualification, safety training; and the development of appropriate processes for identification and abatement of any currently installed, non-compliant devices.

Where NRTL approved devices are required for use in hazardous locations, confirmation of NRTL approval is recommended. In other words, if reconditioned or new surplus devices have been or are currently being purchased, one may need to perform an appropriate risk/regulatory compliance assessment and identify all devices that are no longer NRTL approved.

The following steps offer a straightforward methodology for identification and abatement.

Identification:

  • Ask the purchasing department to provide a list of the suppliers having sold reconditioned or new surplus instruments that are normally NRTL approved (excepting field inspection and certification if such service is available from the NRTL and the number of required field inspections would be small.)
  • Fully qualify each supplier by requiring them to provide up-to-date, NRTL signed documentation demonstrating that the supplier is compliant with the appropriate NRTL position on such reconditioned or new surplus instruments.
  • Identify hazardous (classified) locations and tag numbers where potentially non-compliant instruments are currently installed (including warehouse spares inventory).
  • Walk down the instruments and identify any instruments suspected to be reconditioned or new surplus. Record each instrument’s serial number.
  • Working with the OEM or the OEM’s local distributor, use the instrument serial numbers to identify the original shipping destination when purchased new.
  • If the shipping destination of the instrument, when purchased new, is different from the current end user’s destination, thereby demonstrating prior ownership, then the instrument may need re-certification (unless documented to have been purchased from an NRTL audited and approved re-conditioner or new-surplus supplier).

Abatement:

  • Recertify reconditioned or new surplus instruments that are no longer NRTL approved. Use a qualified supplier for each instrumentation type and manufacturer; i.e., must be an NRTL audited and approved facility within the NRTL’s scope of recognition by OSHA.
  • Start with the warehouse and have any reconditioned or new surplus instruments that are no longer NRTL approved, re-approved by an appropriate NRTL audited facility.
  • Use these re-approved instruments (or use new, approved instruments) as rotational replacements for the non-compliant field instruments.
  • Continue removing, re-approving and replacing non-compliant field instruments on a rotational basis until full abatement is achieved.

Sustaining:

  • Ensure that purchasing, engineering, operating and maintenance personnel work only with qualified and documented suppliers of reconditioned or new surplus instrumentation for use in hazardous locations (NRTL audited and approved by instrument type and manufacturer).
  • Emphasize the requirements for sustaining NRTL approved reconditioned or new surplus instrumentation and that a management of change process (MOC) will be required when a visual replace-in-kind is not truly an equivalent technical replace-in-kind.

Maintenance MOC

As noted, the MOC process should receive increased emphasis to ensure technical equivalency, especially since many reconditioned instruments are often extolled by a non-OEM supplier as "equivalent to factory specifications.”

Such devices may look identical externally, but they may no longer be identical technically. An example is a supplier of reconditioned or new surplus instruments leaving an original manufacturer’s nameplate on a device (containing the original NRTL approval certification mark), and the supplier is not audited or approved by the NRTL. In such circumstances, an MOC evaluation is necessary for installation into a hazardous (classified) location.

For devices where NRTL approval is in question, an efficient method for verification is to review the serial number with the OEM or OEM distributor. They can identify the original shipping destination when purchased new. If the device has changed ownership, there is a high probability that the device was resold as either new surplus or reconditioned.

Supplier Qualification

End users or intermediate resellers of instrumentation can easily and efficiently ensure that reconditioned or new surplus instruments that require NRTL approvals are purchased from NRTL audited and approved entities by requiring the following:

  • Obtain signed, NRTL authored documentation from suppliers of salvaged, refurbished, remanufactured or new surplus electrical/electronic instrumentation that certifies they are audited and approved by the NRTL to apply, re-apply or leave in place an NRTL approval label
  • Verify that NRTL authored documentation lists the specific manufacturer instrument types for which the supplier is audited and approved
  • Require suppliers to provide their NRTL audit frequency, including ongoing submittal of NRTL signed documentation following each successful follow-up audit

Summary

FM Approvals, LLC, an OSHA accredited NRTL, has gone on record with respect to its approval validation of previously certified products that are subsequently resold into the marketplace after being salvaged, refurbished, remanufactured or resold as new surplus.

Across the process industry, reconditioned and new surplus instrumentation has been incorrectly perceived as sustaining its NRTL approval for use in hazardous (classified) locations, resulting in a growing presence of such non-approved devices. The proliferation of electrical/electronic instruments that are no longer NRTL approved increases the statistical possibility of a catastrophic, explosive incident.

By better understanding and addressing the issues now, appropriate actions and emphasis can be incorporated into hazard identification and process safety management programs, resulting in safer work environments.


1 Frier, Len: "What Electrical Inspectors Don’t See,” IAEI News (May/June 2002); available fromwww.iaei.org

2 ANSI / NFPA 70-1996,National Electrical Code

3 CSA Standard C22.1-98, Canadian Electrical Code

4 U.S. Department of Labor, Occupational Safety & Health Administration

5 Martell, Robert L.: Assistant Vice President, FM Approvals Director, FM Approvals LLC


 

About Robert (Bob) Baker: Robert Baker is vice president of John H. Carter Company, Inc., in Baton Rouge, Louisiana, on contract with Emerson Process Management. He specializes in process safety management issues in hydrocarbon and chemical processing industries.

Tags:  Featured  July-August 2006 

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Buyers Beware: Electrical Instrumentation for Use in Hazardous Locations

Posted By Robert (Bob) Baker, Saturday, July 01, 2006
Updated: Sunday, February 10, 2013

Buyers of salvaged, remanufactured, refurbished or new surplus electrical instrumentation for use in hazardous locations (including chemical process plants, refineries, and other industries/applications which are classified as hazardous) need to exercise caution in their instrumentation purchases. Doing so is especially important given the increased market for these items, which experts estimate at $100 million for the process industry and growing. There are several factors responsible for the rapid growth in this market: industry pressure for cost containment (maintenance budgets and small, local capital projects), increased overseas competition and the ongoing closure of North American chemical and hydrocarbon processing facilities.


Photo 1

Len Frier’s May/June 2002 IAEI News article noting that "beauty is only skin deep” could not be more appropriate when dealing with the above types of resold electrical instrumentation,1 especially when those instruments are to be used in hazardous (classified) locations as defined by the National Electric Code2 and the Canadian Electrical Code 3 with regulatory requirements such as Occupational Safety and Health Administration (OSHA) 1910.307. 4 This article is one way of generating process industry awareness of the potential safety risk posed by this instrumentation as well as the risk of regulatory non-conformance. By better understanding how salvaged, remanufactured, refurbished and new surplus electrical instrumentation is certified, buyers can better ensure that their safety management programs meet their needs, helping to provide safer work environments.


Photo 2

There is little process industry awareness of the fact that some nationally recognized testing laboratory (NRTL) instrument certifications may no longer comply with the defined standards to which they were originally certified. Such instruments include salvaged, remanufactured, refurbished or re-marketed as new surplus, even though the reselling entity leaves the original manufacturer’s nameplate containing an NRTL approval mark on the instrument. To date, buyers and installers have assumed that they have purchased replacement-in-kind instruments when, unfortunately, they may not be replacement-in-kind. These purchases require increased scrutiny, including management of change (MOC) evaluations, to better ensure that plant design standards and regulatory requirements are met.

This article will outline steps buyers can take to ensure that their salvaged, remanufactured, refurbished or new surplus electrical instrumentation meets requirements for use in hazardous (classified) locations. Before delving into these solutions, it is important to clarify some definitions.

Definitions

Reconditioned refers to any form of salvaged, refurbished, or remanufactured instrumentation. Transfer of instrument ownership has typically taken place during a reconditioning process with limited, if any, traceability associated with the instrument’s prior application, environmental conditions, handling, maintenance history, use of OEM parts during repairs, etc.

New Surplusis defined as unused current or obsolete instrumentation, which:

  • May or may not still be in the original packaging
  • May have been in end user, distributor or other intermediary inventory since original manufacture
  • May have been previously installed, calibrated and subsequently removed and repackaged without actually being started up.
  • May have had multiple ownership transfers without the instrument ever having been used

More traceability typically exists for new surplus instrumentation than for reconditioned instrumentation, but it is still usually limited. With new surplus instruments subjected to the scenarios outlined in the bullets above, the opportunity exists for unknown changes or hidden damage over the typically lengthy time and handling between original manufacture and subsequent resale.

Product Certification


Photo 3

OSHA safety standards contain requirements for "approval” (i.e., testing and certification) of certain products by a NRTL. These safety standards are found in Title 29 of the Code of Federal Regulations (29 CFR), and the provisions for NRTL certification are generally in Part 1910 (29 CFR Part 1910).4

OSHA recognition of an NRTL is an acknowledgement that the organization has the necessary qualifications to perform safety testing and can "properly certify” the specific products covered within its scope of recognition.4

Properly certified generally means:4

1. The product is labeled or marked with the registered certification mark of the NRTL.
2. The NRTL issues the certification for a product covered within the scope of a test standard for which OSHA has recognized it.
3. The NRTL issues the certification from one of its sites (i.e., locations) that OSHA has recognized.

NRTL Certification Positions

Of the NRTLs OSHA recognizes for the testing and certifying of instrumentation for use in hazardous (classified) locations, FM Approvals, LLC, a member of the FM Global Group has, to date, established its formal position regarding their approval certification mark for refurbished or new surplus product.

"It is FM Approvals’ position that only the original manufacturer of the approved product or an FM Approved remanufacturer whose facilities are part of the FM Approvals follow-up audit program, can remanufacture a product and reissue the FM Approvals certification mark. Any suggestion, practice or inference to the contrary is wrong and must cease.”

Further: "Any salvaged, remanufactured or new surplus electrical instrument cannot be labeled or relabeled as FM Approved for use in a classified hazardous location unless the refurbishing/new surplus supplier entity is audited and approved by FM Approvals, LLC, for that specific type of instrument.”

"Absent the above being met, the device can carry the FM Approvals certification only if the product has been resubmitted and approval granted by FM Approvals. Failure to follow these guidelines will invalidate the FM Approvals certifications. In such instances the FM Approvals certification mark shall be permanently removed from the product (including the nameplate).” 5


Photo 4

To date, the above position has not been well understood, especially in industries having plant/process unit areas classified as hazardous due to the potential presence of ignitable or combustible chemicals, hydrocarbons or dust, as defined by NEC,2 CEC,3 et al.

The typical perception is that an electrical/electronic instrument, once NRTL approved at the factory, remains NRTL approved for the life of the device. This perception is a major concern and results from the original equipment manufacturer (OEM) nameplate usually being left on reconditioned or new surplus instruments by a supplier which may not be audited or approved by the NRTL to do so. This is typically the situation even though there may be other non-OEM markings identifying the instruments as having been reconditioned. See example photo comparisons below.

Thus, both suppliers and purchasers may incorrectly perceive that reconditioned instruments meet engineering or maintenance specifications that require NRTL approval to sustain plant design standards and to comply with regulatory safety requirements. The FM Approvals position is clear that such is not the case; i.e, instruments are no longer approved, and its NRTL approval labeling should be removed. Without NRTL certification, these devices are no longer approved as safe for use in hazardous (classified) locations, thus presumably increasing the risk of a catastrophic accident. A management of change (MOC) evaluation would be necessary if these devices were considered for use in a location classified as hazardous.

Although the use of non-approved instrumentation may not yet have resulted in a catastrophic, explosive incident to date, it may be naïve to assume an accident will not happen in the future.

Typically, safety experts have embraced the philosophy that "just because there hasn’t been an accident in the past does not mean that the combination of situations required to cause an accident will not occur in the future.” However, in addition to the safety issue, the potential regulatory non‑compliance certainly creates additional financial exposure should an incident occur, especially if the incident involves personal injury or death.

Solutions

Within a process safety management program (PSM), including process hazard analysis (PHA), emphasis is needed to ensure hazard identification; adequate risk assessments; detailed attention to instrument specifications by engineering, purchasing and maintenance; supplier qualification, safety training; and the development of appropriate processes for identification and abatement of any currently installed, non-compliant devices.

Where NRTL approved devices are required for use in hazardous locations, confirmation of NRTL approval is recommended. In other words, if reconditioned or new surplus devices have been or are currently being purchased, one may need to perform an appropriate risk/regulatory compliance assessment and identify all devices that are no longer NRTL approved.

The following steps offer a straightforward methodology for identification and abatement.

Identification:

  • Ask the purchasing department to provide a list of the suppliers having sold reconditioned or new surplus instruments that are normally NRTL approved (excepting field inspection and certification if such service is available from the NRTL and the number of required field inspections would be small.)
  • Fully qualify each supplier by requiring them to provide up-to-date, NRTL signed documentation demonstrating that the supplier is compliant with the appropriate NRTL position on such reconditioned or new surplus instruments.
  • Identify hazardous (classified) locations and tag numbers where potentially non-compliant instruments are currently installed (including warehouse spares inventory).
  • Walk down the instruments and identify any instruments suspected to be reconditioned or new surplus. Record each instrument’s serial number.
  • Working with the OEM or the OEM’s local distributor, use the instrument serial numbers to identify the original shipping destination when purchased new.
  • If the shipping destination of the instrument, when purchased new, is different from the current end user’s destination, thereby demonstrating prior ownership, then the instrument may need re-certification (unless documented to have been purchased from an NRTL audited and approved re-conditioner or new-surplus supplier).

Abatement:

  • Recertify reconditioned or new surplus instruments that are no longer NRTL approved. Use a qualified supplier for each instrumentation type and manufacturer; i.e., must be an NRTL audited and approved facility within the NRTL’s scope of recognition by OSHA.
  • Start with the warehouse and have any reconditioned or new surplus instruments that are no longer NRTL approved, re-approved by an appropriate NRTL audited facility.
  • Use these re-approved instruments (or use new, approved instruments) as rotational replacements for the non-compliant field instruments.
  • Continue removing, re-approving and replacing non-compliant field instruments on a rotational basis until full abatement is achieved.

Sustaining:

  • Ensure that purchasing, engineering, operating and maintenance personnel work only with qualified and documented suppliers of reconditioned or new surplus instrumentation for use in hazardous locations (NRTL audited and approved by instrument type and manufacturer).
  • Emphasize the requirements for sustaining NRTL approved reconditioned or new surplus instrumentation and that a management of change process (MOC) will be required when a visual replace-in-kind is not truly an equivalent technical replace-in-kind.

Maintenance MOC

As noted, the MOC process should receive increased emphasis to ensure technical equivalency, especially since many reconditioned instruments are often extolled by a non-OEM supplier as "equivalent to factory specifications.”

Such devices may look identical externally, but they may no longer be identical technically. An example is a supplier of reconditioned or new surplus instruments leaving an original manufacturer’s nameplate on a device (containing the original NRTL approval certification mark), and the supplier is not audited or approved by the NRTL. In such circumstances, an MOC evaluation is necessary for installation into a hazardous (classified) location.

For devices where NRTL approval is in question, an efficient method for verification is to review the serial number with the OEM or OEM distributor. They can identify the original shipping destination when purchased new. If the device has changed ownership, there is a high probability that the device was resold as either new surplus or reconditioned.

Supplier Qualification

End users or intermediate resellers of instrumentation can easily and efficiently ensure that reconditioned or new surplus instruments that require NRTL approvals are purchased from NRTL audited and approved entities by requiring the following:

  • Obtain signed, NRTL authored documentation from suppliers of salvaged, refurbished, remanufactured or new surplus electrical/electronic instrumentation that certifies they are audited and approved by the NRTL to apply, re-apply or leave in place an NRTL approval label
  • Verify that NRTL authored documentation lists the specific manufacturer instrument types for which the supplier is audited and approved
  • Require suppliers to provide their NRTL audit frequency, including ongoing submittal of NRTL signed documentation following each successful follow-up audit

Summary

FM Approvals, LLC, an OSHA accredited NRTL, has gone on record with respect to its approval validation of previously certified products that are subsequently resold into the marketplace after being salvaged, refurbished, remanufactured or resold as new surplus.

Across the process industry, reconditioned and new surplus instrumentation has been incorrectly perceived as sustaining its NRTL approval for use in hazardous (classified) locations, resulting in a growing presence of such non-approved devices. The proliferation of electrical/electronic instruments that are no longer NRTL approved increases the statistical possibility of a catastrophic, explosive incident.

By better understanding and addressing the issues now, appropriate actions and emphasis can be incorporated into hazard identification and process safety management programs, resulting in safer work environments.


1 Frier, Len: "What Electrical Inspectors Don’t See,” IAEI News (May/June 2002); available from www.iaei.org

2 ANSI / NFPA 70-1996,National Electrical Code

3 CSA Standard C22.1-98, Canadian Electrical Code

4 U.S. Department of Labor, Occupational Safety & Health Administration

5 Martell, Robert L.: Assistant Vice President, FM Approvals Director, FM Approvals LLC


 

About Robert (Bob) Baker: Robert Baker is vice president of John H. Carter Company, Inc., in Baton Rouge, Louisiana, on contract with Emerson Process Management. He specializes in process safety management issues in hydrocarbon and chemical processing industries.

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Buyers Beware: Electrical Instrumentation for Use in Hazardous Locations

Posted By Robert (Bob) Baker, Saturday, July 01, 2006
Updated: Sunday, February 10, 2013

Buyers of salvaged, remanufactured, refurbished or new surplus electrical instrumentation for use in hazardous locations (including chemical process plants, refineries, and other industries/applications which are classified as hazardous) need to exercise caution in their instrumentation purchases. Doing so is especially important given the increased market for these items, which experts estimate at $100 million for the process industry and growing. There are several factors responsible for the rapid growth in this market: industry pressure for cost containment (maintenance budgets and small, local capital projects), increased overseas competition and the ongoing closure of North American chemical and hydrocarbon processing facilities.


Photo 1

Len Frier’s May/June 2002 IAEI News article noting that "beauty is only skin deep” could not be more appropriate when dealing with the above types of resold electrical instrumentation,1 especially when those instruments are to be used in hazardous (classified) locations as defined by the National Electric Code2 and the Canadian Electrical Code 3 with regulatory requirements such as Occupational Safety and Health Administration (OSHA) 1910.307. 4 This article is one way of generating process industry awareness of the potential safety risk posed by this instrumentation as well as the risk of regulatory non-conformance. By better understanding how salvaged, remanufactured, refurbished and new surplus electrical instrumentation is certified, buyers can better ensure that their safety management programs meet their needs, helping to provide safer work environments.


Photo 2

There is little process industry awareness of the fact that some nationally recognized testing laboratory (NRTL) instrument certifications may no longer comply with the defined standards to which they were originally certified. Such instruments include salvaged, remanufactured, refurbished or re-marketed as new surplus, even though the reselling entity leaves the original manufacturer’s nameplate containing an NRTL approval mark on the instrument. To date, buyers and installers have assumed that they have purchased replacement-in-kind instruments when, unfortunately, they may not be replacement-in-kind. These purchases require increased scrutiny, including management of change (MOC) evaluations, to better ensure that plant design standards and regulatory requirements are met.

This article will outline steps buyers can take to ensure that their salvaged, remanufactured, refurbished or new surplus electrical instrumentation meets requirements for use in hazardous (classified) locations. Before delving into these solutions, it is important to clarify some definitions.

Definitions

Reconditioned refers to any form of salvaged, refurbished, or remanufactured instrumentation. Transfer of instrument ownership has typically taken place during a reconditioning process with limited, if any, traceability associated with the instrument’s prior application, environmental conditions, handling, maintenance history, use of OEM parts during repairs, etc.

New Surplusis defined as unused current or obsolete instrumentation, which:

  • May or may not still be in the original packaging
  • May have been in end user, distributor or other intermediary inventory since original manufacture
  • May have been previously installed, calibrated and subsequently removed and repackaged without actually being started up.
  • May have had multiple ownership transfers without the instrument ever having been used

More traceability typically exists for new surplus instrumentation than for reconditioned instrumentation, but it is still usually limited. With new surplus instruments subjected to the scenarios outlined in the bullets above, the opportunity exists for unknown changes or hidden damage over the typically lengthy time and handling between original manufacture and subsequent resale.

Product Certification


Photo 3

OSHA safety standards contain requirements for "approval” (i.e., testing and certification) of certain products by a NRTL. These safety standards are found in Title 29 of the Code of Federal Regulations (29 CFR), and the provisions for NRTL certification are generally in Part 1910 (29 CFR Part 1910).4

OSHA recognition of an NRTL is an acknowledgement that the organization has the necessary qualifications to perform safety testing and can "properly certify” the specific products covered within its scope of recognition.4

Properly certified generally means:4

1. The product is labeled or marked with the registered certification mark of the NRTL.
2. The NRTL issues the certification for a product covered within the scope of a test standard for which OSHA has recognized it.
3. The NRTL issues the certification from one of its sites (i.e., locations) that OSHA has recognized.

NRTL Certification Positions

Of the NRTLs OSHA recognizes for the testing and certifying of instrumentation for use in hazardous (classified) locations, FM Approvals, LLC, a member of the FM Global Group has, to date, established its formal position regarding their approval certification mark for refurbished or new surplus product.

"It is FM Approvals’ position that only the original manufacturer of the approved product or an FM Approved remanufacturer whose facilities are part of the FM Approvals follow-up audit program, can remanufacture a product and reissue the FM Approvals certification mark. Any suggestion, practice or inference to the contrary is wrong and must cease.”

Further: "Any salvaged, remanufactured or new surplus electrical instrument cannot be labeled or relabeled as FM Approved for use in a classified hazardous location unless the refurbishing/new surplus supplier entity is audited and approved by FM Approvals, LLC, for that specific type of instrument.”

"Absent the above being met, the device can carry the FM Approvals certification only if the product has been resubmitted and approval granted by FM Approvals. Failure to follow these guidelines will invalidate the FM Approvals certifications. In such instances the FM Approvals certification mark shall be permanently removed from the product (including the nameplate).” 5


Photo 4

To date, the above position has not been well understood, especially in industries having plant/process unit areas classified as hazardous due to the potential presence of ignitable or combustible chemicals, hydrocarbons or dust, as defined by NEC,2 CEC,3 et al.

The typical perception is that an electrical/electronic instrument, once NRTL approved at the factory, remains NRTL approved for the life of the device. This perception is a major concern and results from the original equipment manufacturer (OEM) nameplate usually being left on reconditioned or new surplus instruments by a supplier which may not be audited or approved by the NRTL to do so. This is typically the situation even though there may be other non-OEM markings identifying the instruments as having been reconditioned. See example photo comparisons below.

Thus, both suppliers and purchasers may incorrectly perceive that reconditioned instruments meet engineering or maintenance specifications that require NRTL approval to sustain plant design standards and to comply with regulatory safety requirements. The FM Approvals position is clear that such is not the case; i.e, instruments are no longer approved, and its NRTL approval labeling should be removed. Without NRTL certification, these devices are no longer approved as safe for use in hazardous (classified) locations, thus presumably increasing the risk of a catastrophic accident. A management of change (MOC) evaluation would be necessary if these devices were considered for use in a location classified as hazardous.

Although the use of non-approved instrumentation may not yet have resulted in a catastrophic, explosive incident to date, it may be naïve to assume an accident will not happen in the future.

Typically, safety experts have embraced the philosophy that "just because there hasn’t been an accident in the past does not mean that the combination of situations required to cause an accident will not occur in the future.” However, in addition to the safety issue, the potential regulatory non‑compliance certainly creates additional financial exposure should an incident occur, especially if the incident involves personal injury or death.

Solutions

Within a process safety management program (PSM), including process hazard analysis (PHA), emphasis is needed to ensure hazard identification; adequate risk assessments; detailed attention to instrument specifications by engineering, purchasing and maintenance; supplier qualification, safety training; and the development of appropriate processes for identification and abatement of any currently installed, non-compliant devices.

Where NRTL approved devices are required for use in hazardous locations, confirmation of NRTL approval is recommended. In other words, if reconditioned or new surplus devices have been or are currently being purchased, one may need to perform an appropriate risk/regulatory compliance assessment and identify all devices that are no longer NRTL approved.

The following steps offer a straightforward methodology for identification and abatement.

Identification:

  • Ask the purchasing department to provide a list of the suppliers having sold reconditioned or new surplus instruments that are normally NRTL approved (excepting field inspection and certification if such service is available from the NRTL and the number of required field inspections would be small.)
  • Fully qualify each supplier by requiring them to provide up-to-date, NRTL signed documentation demonstrating that the supplier is compliant with the appropriate NRTL position on such reconditioned or new surplus instruments.
  • Identify hazardous (classified) locations and tag numbers where potentially non-compliant instruments are currently installed (including warehouse spares inventory).
  • Walk down the instruments and identify any instruments suspected to be reconditioned or new surplus. Record each instrument’s serial number.
  • Working with the OEM or the OEM’s local distributor, use the instrument serial numbers to identify the original shipping destination when purchased new.
  • If the shipping destination of the instrument, when purchased new, is different from the current end user’s destination, thereby demonstrating prior ownership, then the instrument may need re-certification (unless documented to have been purchased from an NRTL audited and approved re-conditioner or new-surplus supplier).

Abatement:

  • Recertify reconditioned or new surplus instruments that are no longer NRTL approved. Use a qualified supplier for each instrumentation type and manufacturer; i.e., must be an NRTL audited and approved facility within the NRTL’s scope of recognition by OSHA.
  • Start with the warehouse and have any reconditioned or new surplus instruments that are no longer NRTL approved, re-approved by an appropriate NRTL audited facility.
  • Use these re-approved instruments (or use new, approved instruments) as rotational replacements for the non-compliant field instruments.
  • Continue removing, re-approving and replacing non-compliant field instruments on a rotational basis until full abatement is achieved.

Sustaining:

  • Ensure that purchasing, engineering, operating and maintenance personnel work only with qualified and documented suppliers of reconditioned or new surplus instrumentation for use in hazardous locations (NRTL audited and approved by instrument type and manufacturer).
  • Emphasize the requirements for sustaining NRTL approved reconditioned or new surplus instrumentation and that a management of change process (MOC) will be required when a visual replace-in-kind is not truly an equivalent technical replace-in-kind.

Maintenance MOC

As noted, the MOC process should receive increased emphasis to ensure technical equivalency, especially since many reconditioned instruments are often extolled by a non-OEM supplier as "equivalent to factory specifications.”

Such devices may look identical externally, but they may no longer be identical technically. An example is a supplier of reconditioned or new surplus instruments leaving an original manufacturer’s nameplate on a device (containing the original NRTL approval certification mark), and the supplier is not audited or approved by the NRTL. In such circumstances, an MOC evaluation is necessary for installation into a hazardous (classified) location.

For devices where NRTL approval is in question, an efficient method for verification is to review the serial number with the OEM or OEM distributor. They can identify the original shipping destination when purchased new. If the device has changed ownership, there is a high probability that the device was resold as either new surplus or reconditioned.

Supplier Qualification

End users or intermediate resellers of instrumentation can easily and efficiently ensure that reconditioned or new surplus instruments that require NRTL approvals are purchased from NRTL audited and approved entities by requiring the following:

  • Obtain signed, NRTL authored documentation from suppliers of salvaged, refurbished, remanufactured or new surplus electrical/electronic instrumentation that certifies they are audited and approved by the NRTL to apply, re-apply or leave in place an NRTL approval label
  • Verify that NRTL authored documentation lists the specific manufacturer instrument types for which the supplier is audited and approved
  • Require suppliers to provide their NRTL audit frequency, including ongoing submittal of NRTL signed documentation following each successful follow-up audit

Summary

FM Approvals, LLC, an OSHA accredited NRTL, has gone on record with respect to its approval validation of previously certified products that are subsequently resold into the marketplace after being salvaged, refurbished, remanufactured or resold as new surplus.

Across the process industry, reconditioned and new surplus instrumentation has been incorrectly perceived as sustaining its NRTL approval for use in hazardous (classified) locations, resulting in a growing presence of such non-approved devices. The proliferation of electrical/electronic instruments that are no longer NRTL approved increases the statistical possibility of a catastrophic, explosive incident.

By better understanding and addressing the issues now, appropriate actions and emphasis can be incorporated into hazard identification and process safety management programs, resulting in safer work environments.


1 Frier, Len: "What Electrical Inspectors Don’t See,” IAEI News (May/June 2002); available from www.iaei.org

2 ANSI / NFPA 70-1996,National Electrical Code

3 CSA Standard C22.1-98, Canadian Electrical Code

4 U.S. Department of Labor, Occupational Safety & Health Administration

5 Martell, Robert L.: Assistant Vice President, FM Approvals Director, FM Approvals LLC


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Analysis of Changes, Part 1, NEC-2008

Posted By Michael Johnston , Saturday, July 01, 2006
Updated: Sunday, February 10, 2013

Revisions to the NEC are inevitable, and given the unique and important nature of this electrical safety standard, very necessary. The NEC development process is ever dynamic and ongoing, because new technologies are continuously entering the electrical market and code rules must be developed or revised to address electrical safety concerns related to these new materials, equipment, emerging methods or technologies. There were 3,688 proposals, including all technical committee proposals, to change NEC-2008. These proposed changes were acted on by the technical committees at the Report on Proposals (ROP) meetings held in January 2006. This article provides an overview based on code-making panel actions taken on the proposals in the first stage of the development process.

These changes could be affected by subsequent CMP actions on public comments to the proposed revisions.

NFPA’s Report on Proposals includes all proposed changes and related technical committee actions and statements, and is published for public review and comment. Public comments to proposed changes are due to NFPA by October 20, 2006 (5:00 P.M. EST). The development process is an open consensus process in which involvement by everyone is encouraged. Forms for submitting comments are provided on the NFPA website and in the back of the Report on Proposals.

This article is Part I of a series that visits some of the more significant revisions proposed and accepted for NEC-2008.

Code-Wide Revisions

A few revisions were accepted that affect the entire NEC. Three such changes include (1) procedural changes in how the definitions of words and terms are handled by the technical committees, (2) grounding and bonding definitions and terminology revisions, and (3) two new definitions of the terms neutral conductor and neutral point.

Change in Procedures
The NEC-2008 development process included a shift in responsibility for any technical definitions that fall under the scope of responsibility of certain NEC technical committees. Traditionally all of the definitions in Article 100 were the responsibility of code-making panel 1. Action by the NEC Technical Correlating Committee (TCC) results in each code-making panel being responsible for definitions of words and terms that are under its responsibility, but these definitions will continue to be located in Article 100. Definitions that are general in nature will continue to be assigned to code-making panel 1. This change will result in more accurately defined words and consistent correlation of terms throughout the NEC.

Grounding and Bonding
Terms and Rules

A task group was assembled to explore several significant issues regarding grounding and bonding terminology used the Code. The definitions affected by the work of the task group are as follows:

Bonding (Bonded)– revised
Grounding Electrode Conductor– revised
Grounding Conductor, Equipment– revised
Grounding Electrode– revised
Ground– revised
Grounding (Grounded)– revised
Grounded, Effectively– deleted
Ungrounded– new

Where revisions were necessary, the task group developed and submitted proposals to each NEC technical committee. In many cases, revisions provided specific direction for users. The changes in one instance resulted in changing the term shall be grounded to the wording "shall be connected to an equipment grounded conductor” where that was the original intention of the requirement.

The definition of effectively grounded was deleted because the term is subjective and has no specific parameters for making determinations as to whether or not something is effectively grounded. Instances where it was used in previous editions of the Code have been revised to remove the word "effectively” from the phrase.

New Definitions of Neutral Conductor and Neutral Point


Figure 1. Neutral conductor and neutral point are defined

These definitions have been incorporated into Article 100 to differentiate between a neutral conductor of a system and a neutral point (termination point for neutral conductors) within NEC rules where the terms are used (see figure 1).

Aneutral conductor is intended to carry current under normal operation. In power systems, the neutral conductors are typically the grounded conductor, but not all grounded conductors are neutral conductors.

Aneutral point relates to a common connection point for a neutral conductor connection at the source or system windings.

The rules throughout the NEC that include the word "neutral” have been clarified to be specific to either the neutral conductor or the neutral point of a supply system.

Chapter One – General

Article 100 Definitions


Figure 2. Example of bundled cables

Several definitions in Article 100 have been revised, and a few new definitions have been added.

Bundled.Cables or conductors that are physically tied, wrapped, taped or otherwise periodically bound together. [Relocated from 520.2 to Article 100, see figure 2]

Clothes Closet.A non-habitable room or space intended primarily for storage of garments and apparel. [New definition, see figure 3]

Equipotential Plane.An area where mesh or other conductive elements are embedded in or


Figure 3. Clothes closet


Figure 4. Handhole enclosure defined

placed under concrete or other conductive surface, are bonded together and to all metal structures and fixed nonelectrical equipment that may become energized, and are connected to the electrical grounding system. [Incorporates two concepts into one common term]

Handhole Enclosure.An enclosure for use in underground systems, provided with an open or closed bottom, and sized to allow personnel to reach into, but not enter, for the purpose of installing, operating, or maintaining equipment or wiring or both. [Requirement of identification removed from definition, see figure 4]


Figure 5. Kitchen defined

Kitchen.

An area with a sink and permanent facilities for food preparation and cooking [New definition, see figure 5]

Neutral Conductor. The conductor connected to the neutral point of a system that is intended to carry current under normal conditions. [New definition, see figure 6]

Neutral point. The common point on a wye-connection in a polyphase system or midpoint on a single-phase, 3-wire system, or midpoint of a single-phase portion of a 3-phase delta system, or a midpoint of a 3-wire, direct current system [New definition, see figure 7]


Figure 6. Neutral conductor of a system

FPN: At the neutral point of the system, the vectorial sum of the nominal voltages from all other phases within the system that utilize the neutral, with respect to the neutral point, is zero potential.

Qualified Person.One who has skills and knowledge related to the construction and operation of the electrical equipment and installations and has received safety training to recognize and avoid the hazards involved. [Revised definition, see figure 8]

Article 110 Requirements for Electrical Installations
Revision: 110.16 Flash Protection


Figure 7. Neutral point of a system

Electrical equipment such as… shall be field marked to warn qualified persons of potential electric arc flash hazards.

Analysis.Two changes to 110.16 provide additional clarity and allow for more appropriate and consistent application to field installations that qualify for the warning labels required by this section. The first revision broadens the requirement by including all types of equipment that would qualify for the field-applied arc-flash warning labels (see figure 9). Previous requirements of this section were limited only to the types of equipment actually identified in the rule. By including the words, "equipment such as” the concept of applicability is expanded to all equipment types that are likely to require examination, adjustment, servicing, or maintenance while energized. This requirement applies to items such as enclosed circuit breakers, some transformers, and other equipment not specifically included in the previous text. The second revision places a specific limitation on the types of dwelling


Figure 8. Qualified persons

occupancies covered by these label requirements for equipment. Multiple occupancy dwelling structures such as those in apartment complexes and so forth, where the service equipment and other equipment can be large, definitely qualify for the arc-flash warning labels. The arc-flash warning label requirements do not apply to one- and two-family dwelling units, but arc flash hazards are present in those installations and electrical safety work practices should be followed regardless of the type of occupancy in which the equipment is installed. This rule only addresses where field-applied arc flash warning labels are required. The fine print notes have not been affected by these changes, and still provide appropriate references to other applicable standards that provide relative information about


Figure 9. Arc-flash warning label requriements

safe work practices and guidelines for designing safety signs and labels for equipment.

New Section: 110.20 Enclosure Types
Enclosures …shall be marked with an Enclosure Type number as shown in Table 110.20.

Analysis.Concepts introduced during the 2005 NEC development process cycle ultimately led to creating a new Section 110.20 and relocating existing Table 430.91, which includes enclosure type designations and information about their use, to this section (see figure 10). The information within the relocated table remains essentially the same. The table is now identified as Table 110.20. Electrical enclosures in addition to the enclosures used for motor applications as covered by Article 430 are also required to be suitable for the environment in which they are


Figure 10. Enclosure types

installed. The effect of this change provides consistency between the UL General Information for Electrical Equipment Directory (White Book) category (AALZ) and the NEC, which apply generally to all electrical equipment, not just equipment associated with motor installations covered by Article 430. Relocating requirements of 430.91 and Table 430.91 into general application Article 110 and specifically indicating the types of equipment to which the requirements apply add clarity. All of the equipment types in the list are required by existing industry product standards to use a Type number marking.

Revision: 110.22. Identification of Disconnecting Means


Figure 11. Field labels are required for engineered series combinations of overcurrent protective devices

…. The marking shall be readily visible and state the following:
CAUTION — ENGINEERED SERIES COMBINATION
SYSTEM RATED _______ AMPERES. IDENTIFIED
REPLACEMENT COMPONENTS REQUIRED.

FPN: See 240.86(A) for interrupting rating marking for end-use equipment.

Analysis.Section 240.86 was revised in NEC-2005 to include an alternate method of applying a series rated combination of overcurrent devices that is selected under engineering supervision for existing installations. This alternative provided in 240.86(A) applies to existing installations only and provides a method to allow older existing electrical equipment to remain, where the overcurrent protection is coordinated and selected for the design and application by a licensed professional engineer engaged in the design and maintenance of electrical systems and installations. The primary differences between the requirements in 240.86(B) are that the series combinations covered by the requirements in 240.86(B) are listed and tested devices for use in series rated combinations. The alternative in 240.86(A) allows for a selected engineered design consisting of coordinated overcurrent protection that provides the required protection for equipment in such applications that meets the general requirements of 110.10. The revision to 110.22 incorporates a field-applied labeling requirement for existing equipment that is applied in an engineered series rated combination covered by 240.86(A) [see figure 11]. The new requirements for series rated combination systems labeling parallel the current field-marking rules for listed and tested series rated combinations. The key element of the label is that it includes the wording "engineered series rated combination” and the specific equipment requiring the labels will be as directed by the engineer responsible for the design under this alternative.

Revision: 110.26(C) Large Equipment

Analysis.Action by CMP-1 restores the dimension 1.8 m (6 ft) that applies to the equipment


Figure 12. Size and rating of the equipment are both factors in the requirement for two entrances and egress paths from the working space

rated at 1200 amperes or more that constitutes large equipment covered by this section. The requirement for physical size was removed during the 2005 NEC development process, which presented some challenges for meeting the requirements for two entrances and egress paths from some types of equipment where it was not practical or, in some cases, not possible. For example, a 1200-ampere panelboard that is 900 mm (3 ft) in width would be required to meet the two-entrance requirement as provided in NEC-2005. By restoring the requirement for physical size, building and engineering designs are less impacted by a requirement that is not necessary in all cases. This rule, in addition to many others, has to include minimum dimensions and energy levels that serve as a starting point regarding applicability. Large equipment with lower ampacity ratings, such as 800-ampere or 1000-ampere rated switchboards, and so forth, present similar challenges and safety concerns relative to whether two entrances or egress means are required (see figure 12). The second change inserts a specific distance from equipment at which a personnel door that provides access and egress from the working space must meet certain operational and physical characteristics. Personnel doors located less than 1.8 m (6 ft) from the working space mandated by this section will be required to swing away from the working space and be equipped with suitable hardware that operates under simple pressure as indicated in this requirement.

Revision: 110.33 Entrance to Enclosures and Access to Working Space
(A) Entrance. …. a personnel door(s) that is less than 3.7 m (12 ft) from the working space, the door(s) shall open in the direction of egress and be equipped with panic bars ….

(B) Access to Working Space. Permanent ladders or stairways shall be provided to give safe access to the working space around electric equipment installed on platforms, balconies, or mezzanine floors or in attic or roof rooms or spaces.

Analysis.This revision clarified which enclosures are covered by the requirements for entrance and egress means. The enclosures in 110.31, such as fenced areas, vaults, rooms, closets, and so forth, are required to meet the entrance and access requirements of this section. The new language in the second sentence of 110.33(A) clarifies that the personnel door(s) requirement applies to the working space and not necessarily the room in all cases. The 3.7 m (12 ft) distance is reasonable and provides for safe egress from the area. Currently, some jurisdictions are applying the requirement where the doors are a considerable distance from the working space, such as in large areas or rooms. These revisions should provide clear direction as to when the door is required to swing away from the working space, and when it must be equipped with simple release hardware. Personnel doors that are located 3.7 m (12 ft) or more from the working space mandated by this section will not be required to meet the physical and operational characteristics of this rule.

Chapter Two – Wiring and Protection

Article 210 Branch Circuits
New Section: 210.4(D) Grouping
(D) Grouping. The ungrounded and grounded conductors of each multiwire branch circuit shall be grouped by wire ties or similar means in at least one location within the panelboard or other point of origination.
Exception: The requirement for grouping shall not apply if the circuit enters from a cable or raceway unique to the circuit that makes the grouping obvious.

Analysis.This new section requires grouping the grounded conductor of multiwire branch


Figure 13. Multiwire branch-circuit conductors must be grouped at least once in enclosures such as panelboards or other equipment

circuits with the associated ungrounded conductors of the same multiwire branch circuit. These conductors must all be grouped together at least once at a location within the panelboard or equipment where the conductors of the circuit originate (see figure 13). This new grouping requirement should provide more ready means for workers and inspectors to identify the grounded conductor of a mutliwire branch circuit within the equipment where the circuit originates. The new exception to this rule relaxes this requirement where the entry of the circuit conductors of a cable or raceway makes the association obvious without additional grouping. Examples of installations qualifying under the exception include MC or AC cable assemblies or a raceway that contains only the conductors of the multiwire branch circuit. This change will result in all associated conductors of a multiwire branch circuit, including the grounded conductor, being physically grouped together at least once by wire ties or other means within the branch-circuit overcurrent device enclosure to allow for ease of visual recognition. Installers sometimes use wire ties to group multiple conductors of several branch circuits together while lacing and dressing the circuits in the equipment during the conductor termination process. This practice makes it difficult to identify which grounded (neutral) conductor is associated with the ungrounded conductors of the same multiwire branch circuit within the equipment. The new grouping rule should allow installers and inspectors to more readily identify multiwire branch-circuit conductors within the equipment where these conductors originate, enhancing safety.

Revision: 210.8(A) Dwelling Units
The two existing exceptions to 210.8(A)(2) have been deleted. Additional text added to 210.8(A)(5) indicates that any receptacles installed under the exceptions to 210.8(A)(5) shall not be considered as meeting the requirements of 210.52(G).

Analysis.The exception for receptacles that are not readily accessible has been deleted because the concept of being "readily accessible” is too vague and can lead to inconsistencies in how the requirements are applied. A garage door opener might not be readily accessible to short persons, but very well could be accessible to persons that are taller. The shock protection of this requirement should apply to all persons. Exception No. 2 has been deleted to establish consistency with the GFCI receptacle requirements in 210.8(A)(7) that were expanded in NEC-2005. The product safety standards for appliances covered by this exception require appliances to be manufactured with insulation dielectric leakage levels that do not exceed 0.5 mA. This level of leakage current is far below the 4–6 mA leakage thresholds of Class A ground-fault circuit interrupters manufactured to UL Standard 943. There clearly is no longer a need for either of these exceptions. Deleting the two exceptions creates consistency between the requirements in 210.8(A)(2) and 210.8(A)(7) and enhances the level of shock protection for persons where leakage levels in appliances could develop and present shock hazards that under the previous allowances of the exceptions would otherwise go undetected. Protection by ground-fault circuit interrupters is not related to the location of the receptacle. If cord- and plug-connected utilization equipment (appliances exempted by the previous exceptions) has abnormal or excessive leakage current levels that will trip the GFCI, protection should be provided. Based on the information in the applicable product safety standards, the maximum leakage current for typical cord- and plug-connected equipment (appliances) is 0.5 mA. The trip range for Class A GFCI protective devices is 4–6 mA. In order for this utilization equipment to trip a GFCI protective device, leakage current levels would have to reach 8 to 12 times that permitted by the product standard, creating safety concerns. The fact that the receptacle is not readily accessible will have no impact on the shock hazard protection for persons encountering the utilization equipment.

Revision: 210.12(B) Dwelling Units

Analysis.These revisions simply expand the requirements for arc-fault circuit interrupter


Figure 14. All 15- and 20-ampere branch circuits in dwelling units are required to be protected by arc-fault circuit interrupter protection.

protection to all 15- and 20-ampere branch circuits installed in dwelling units (see figure 14). CMP-2 expanded the AFCI protection requirements to branch-circuit outlets that supply dwelling unit bedrooms in NEC-2005 as a means to enhance safety and gain experience putting the application in an easily defined and limited area. Arc-fault circuit interrupters have been proven effective in detecting and clearing arcing conditions or events in wiring systems before damage and loss could occur. This is the principle objective of this type of protection. Experience has shown that AFCI protective devices also detect numerous wiring errors and, in addition, they have found wiring damage and equipment damage that could have been potential sources of fire where protected only by conventional protection devices. A strong basis for limiting this protection to circuits that supply only dwelling unit bedrooms no longer exists, and the increased protection is needed for other circuits. This expansion will continue the effort to help reduce and minimize fires of electrical origin in dwellings. The second paragraph has been deleted because the effective date for ACFI protective devices coincides with the publication of NEC-2008 and so is no longer necessary. Proposed deadline extensions were rejected by CMP-2, which affirms the panel’s intentions that all AFCI protective devices be combination types as of January 1, 2008.

Revision: 210.62 Show Windows


Figure 15

Analysis. More specific location criteria that must be applied to show window receptacle installations are imposed. The new rule requires the receptacle to be located within 450 mm (18 in.) of the top of any show window (see figure 15). This change provides clear direction on how to meet the placement criteria for show window receptacles, while at the same time providing enforcement with a means to apply the rule more consistently to all show windows. This results in receptacles being located for the convenient and practical use for which they were intended, without having to resort to extension cord use, or other remedial means of supplying power for show window applications that can lead to or result in less than safe conditions.

Article 215 Feeders
Revision: 215.10 Exception No. 3

The provisions of this section shall not apply if ground-fault protection of equipment is provided on the supply side of the feeder and on the load side of any transformer supplying the feeder.

Analysis.The revisions to Exception No. 3 clarify where GFPE is required (see figure 16). The


Figure 16

intent is not to require GFPE on a feeder disconnect if that feeder has GFPE protection provided upstream. However, some are misinterpreting that GFPE could be provided on the primary of a transformer to meet this exception. Of course, GFPE on the primary side of a transformer provides no equipment protection to equipment connected to the secondary since the ground-fault on the secondary only returns current to the secondary of the transformer. The objective is to allow relaxing the GFPE requirement for distribution equipment connected to feeders where a GFPE device is supplied upstream of the feeder, at the service equipment for example. When a transformer is inserted in a feeder, essentially this is a new derived system or source. The requirement for ground-fault protection for equipment is related to the size of the equipment supplied by the feeder as indicated in the rule that this exception follows. Current, including ground-fault current, will always try to return to the source. In this case, the source is the transformer. The GFPE on the supply side of such transformers would not function to protect the equipment in accordance with the requirements of this rule because the ground-fault current would not be attempting to return to the service and utility transformer but to the transformer on the supply side of the feeder. This exception does not apply to field installations where the feeder is derived from a transformer supplied from the service equipment on its supply side. Any GFPE on the supply side used to exempt the feeder disconnect from GFPE must be on the load side of the transformer supplying the feeder.

Article 225 Outside Branch Circuits and Feeders
Revision: 225.39 Rating of Disconnect

Analysis.Sections 225.31 and 225.33 address requirements for disconnecting means in feeders


Figure 17

supplying separate buildings or structures, which are similar to those required for service disconnecting means covered in 230.70 and 230.71. Section 230.80 includes methods of establishing a combined rating for installations where multiple disconnects in separate enclosures are used as the service disconnecting means. Disconnecting means is defined in Article 100 and can be a single disconnect or a group of disconnects. Section 225.39 has been revised by adding a new second sentence to clarify that when more that one switch or circuit breaker is used as the disconnecting means for a feeder supplying a separate building or structure, the combined ratings of the switches or circuit breakers used as the service disconnecting means can be added together to achieve the minimum rating required for the disconnecting means (see figure 17). This revision incorporates methods of establishing combined ratings of several disconnects in 225.39 that are similar to the requirements already provided in 230.80 for services.

Article 230 Services
Revision: 230.44, Exception

Analysis.This revision includes specific labeling requirements that clearly indicate where the


Figure 18

cable tray is being used for service-entrance conductors (see figure 18). The last two sentences were added to ensure that the cable tray containing a barrier separating the service-entrance conductors are clearly identified from feeders and branch circuits installed in the other side of the cable tray. The labels should be visible after the installation of the cable tray since an installer may not be able to differentiate between section/partition of the tray containing the service-entrance conductors and inadvertently install protected conductors with unprotected conductors. Cable trays shall be identified with permanently affixed labels with the wording "Service-Entrance Conductors.”

Revision: 230.79 Rating of Service Disconnect
The service disconnecting means shall have a rating not less than the calculated load to be carried, determined in accordance with Parts III and IV of Article 220.

Analysis.These revisions clarify that the rating of the service disconnect is to be not less that the


Figure 19

calculated load to be carried and not the actual load carried (see figure 19). This revision logically recognizes that the load to be carried can vary from time to time, but a calculated load is the maximum anticipated load the disconnect would need to be capable of handling. The word "calculated” was used to be consistent with the changes in the text in Article 220 and other parts of NEC-2005 where the word "computed” was formerly used. The words "Parts III and VI” were added to be consistent with the NEC Style Manual and to identify the applicable parts of Article 220 to which this section refers.

IAEI’s Analysis of Changes book is all about providing valuable insight as to how the revisions have affected the Code text. Another real important element of reviewing each change and understanding its impact is the analysis through clear and concise language understandable to all Code users. This article is an effort to provide readers with current information about revisions that have been accepted by the technical committees at this stage in the NEC development process. Part II of this article will be in the next issue of the IAEI News and include additional significant proposed changes for NEC-2008.


About Michael Johnston: Michael Johnston is NECA’s executive director of standards and safety. Prior to working with NECA, Mike worked for the International Association of Electrical Inspectors as the director of education, codes and standards. Mike is a member of the IBEW and has experience as an electrical journeyman wireman, foreman and project superintendant. Mike achieved all electrical inspector certifications through IAEI and ICC and has worked as an electrical inspector and electrical inspection field supervisor for the city of Phoenix, AZ. Mike achieved a B.S. in business management from the University of Phoenix. Mike is the chairman of the NEC Correlating Committee and served on NEC CMP-5 in the 2002, 2005, 2008, and chair of CMP-5 representing NECA for the 2011 NEC cycle. Johnston is an active member of ANSI, IAEI, NFPA, ASSE, the NFPA Electrical Section, Education Section, the UL Electrical Council, and National Safety Council.

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Analysis of Changes, Part 1, NEC-2008

Posted By Michael Johnston , Saturday, July 01, 2006
Updated: Sunday, February 10, 2013

Revisions to the NEC are inevitable, and given the unique and important nature of this electrical safety standard, very necessary. The NEC development process is ever dynamic and ongoing, because new technologies are continuously entering the electrical market and code rules must be developed or revised to address electrical safety concerns related to these new materials, equipment, emerging methods or technologies. There were 3,688 proposals, including all technical committee proposals, to change NEC-2008. These proposed changes were acted on by the technical committees at the Report on Proposals (ROP) meetings held in January 2006. This article provides an overview based on code-making panel actions taken on the proposals in the first stage of the development process.

These changes could be affected by subsequent CMP actions on public comments to the proposed revisions.

NFPA’s Report on Proposals includes all proposed changes and related technical committee actions and statements, and is published for public review and comment. Public comments to proposed changes are due to NFPA by October 20, 2006 (5:00 P.M. EST). The development process is an open consensus process in which involvement by everyone is encouraged. Forms for submitting comments are provided on the NFPA website and in the back of the Report on Proposals.

This article is Part I of a series that visits some of the more significant revisions proposed and accepted for NEC-2008.

Code-Wide Revisions

A few revisions were accepted that affect the entire NEC. Three such changes include (1) procedural changes in how the definitions of words and terms are handled by the technical committees, (2) grounding and bonding definitions and terminology revisions, and (3) two new definitions of the terms neutral conductor and neutral point.

Change in Procedures
The NEC-2008 development process included a shift in responsibility for any technical definitions that fall under the scope of responsibility of certain NEC technical committees. Traditionally all of the definitions in Article 100 were the responsibility of code-making panel 1. Action by the NEC Technical Correlating Committee (TCC) results in each code-making panel being responsible for definitions of words and terms that are under its responsibility, but these definitions will continue to be located in Article 100. Definitions that are general in nature will continue to be assigned to code-making panel 1. This change will result in more accurately defined words and consistent correlation of terms throughout the NEC.

Grounding and Bonding
Terms and Rules

A task group was assembled to explore several significant issues regarding grounding and bonding terminology used the Code. The definitions affected by the work of the task group are as follows:

Bonding (Bonded)– revised
Grounding Electrode Conductor– revised
Grounding Conductor, Equipment– revised
Grounding Electrode– revised
Ground– revised
Grounding (Grounded)– revised
Grounded, Effectively– deleted
Ungrounded– new

Where revisions were necessary, the task group developed and submitted proposals to each NEC technical committee. In many cases, revisions provided specific direction for users. The changes in one instance resulted in changing the term shall be grounded to the wording "shall be connected to an equipment grounded conductor” where that was the original intention of the requirement.

The definition of effectively grounded was deleted because the term is subjective and has no specific parameters for making determinations as to whether or not something is effectively grounded. Instances where it was used in previous editions of the Code have been revised to remove the word "effectively” from the phrase.

New Definitions of Neutral Conductor and Neutral Point


Figure 1. Neutral conductor and neutral point are defined

These definitions have been incorporated into Article 100 to differentiate between a neutral conductor of a system and a neutral point (termination point for neutral conductors) within NEC rules where the terms are used (see figure 1).

Aneutral conductor is intended to carry current under normal operation. In power systems, the neutral conductors are typically the grounded conductor, but not all grounded conductors are neutral conductors.

Aneutral point relates to a common connection point for a neutral conductor connection at the source or system windings.

The rules throughout the NEC that include the word "neutral” have been clarified to be specific to either the neutral conductor or the neutral point of a supply system.

Chapter One – General

Article 100 Definitions


Figure 2. Example of bundled cables

Several definitions in Article 100 have been revised, and a few new definitions have been added.

Bundled.Cables or conductors that are physically tied, wrapped, taped or otherwise periodically bound together. [Relocated from 520.2 to Article 100, see figure 2]

Clothes Closet.A non-habitable room or space intended primarily for storage of garments and apparel. [New definition, see figure 3]

Equipotential Plane.An area where mesh or other conductive elements are embedded in or


Figure 3. Clothes closet


Figure 4. Handhole enclosure defined

placed under concrete or other conductive surface, are bonded together and to all metal structures and fixed nonelectrical equipment that may become energized, and are connected to the electrical grounding system. [Incorporates two concepts into one common term]

Handhole Enclosure.An enclosure for use in underground systems, provided with an open or closed bottom, and sized to allow personnel to reach into, but not enter, for the purpose of installing, operating, or maintaining equipment or wiring or both. [Requirement of identification removed from definition, see figure 4]

 


Figure 5. Kitchen defined

Kitchen.

An area with a sink and permanent facilities for food preparation and cooking [New definition, see figure 5]

Neutral Conductor. The conductor connected to the neutral point of a system that is intended to carry current under normal conditions. [New definition, see figure 6]

Neutral point. The common point on a wye-connection in a polyphase system or midpoint on a single-phase, 3-wire system, or midpoint of a single-phase portion of a 3-phase delta system, or a midpoint of a 3-wire, direct current system [New definition, see figure 7]


Figure 6. Neutral conductor of a system

FPN: At the neutral point of the system, the vectorial sum of the nominal voltages from all other phases within the system that utilize the neutral, with respect to the neutral point, is zero potential.

Qualified Person.One who has skills and knowledge related to the construction and operation of the electrical equipment and installations and has received safety training to recognize and avoid the hazards involved. [Revised definition, see figure 8]

Article 110 Requirements for Electrical Installations
Revision: 110.16 Flash Protection


Figure 7. Neutral point of a system

Electrical equipment such as… shall be field marked to warn qualified persons of potential electric arc flash hazards.

Analysis.Two changes to 110.16 provide additional clarity and allow for more appropriate and consistent application to field installations that qualify for the warning labels required by this section. The first revision broadens the requirement by including all types of equipment that would qualify for the field-applied arc-flash warning labels (see figure 9). Previous requirements of this section were limited only to the types of equipment actually identified in the rule. By including the words, "equipment such as” the concept of applicability is expanded to all equipment types that are likely to require examination, adjustment, servicing, or maintenance while energized. This requirement applies to items such as enclosed circuit breakers, some transformers, and other equipment not specifically included in the previous text. The second revision places a specific limitation on the types of dwelling


Figure 8. Qualified persons

occupancies covered by these label requirements for equipment. Multiple occupancy dwelling structures such as those in apartment complexes and so forth, where the service equipment and other equipment can be large, definitely qualify for the arc-flash warning labels. The arc-flash warning label requirements do not apply to one- and two-family dwelling units, but arc flash hazards are present in those installations and electrical safety work practices should be followed regardless of the type of occupancy in which the equipment is installed. This rule only addresses where field-applied arc flash warning labels are required. The fine print notes have not been affected by these changes, and still provide appropriate references to other applicable standards that provide relative information about


Figure 9. Arc-flash warning label requriements

safe work practices and guidelines for designing safety signs and labels for equipment.

New Section: 110.20 Enclosure Types
Enclosures …shall be marked with an Enclosure Type number as shown in Table 110.20.

Analysis.Concepts introduced during the 2005 NEC development process cycle ultimately led to creating a new Section 110.20 and relocating existing Table 430.91, which includes enclosure type designations and information about their use, to this section (see figure 10). The information within the relocated table remains essentially the same. The table is now identified as Table 110.20. Electrical enclosures in addition to the enclosures used for motor applications as covered by Article 430 are also required to be suitable for the environment in which they are


Figure 10. Enclosure types

installed. The effect of this change provides consistency between the UL General Information for Electrical Equipment Directory (White Book) category (AALZ) and the NEC, which apply generally to all electrical equipment, not just equipment associated with motor installations covered by Article 430. Relocating requirements of 430.91 and Table 430.91 into general application Article 110 and specifically indicating the types of equipment to which the requirements apply add clarity. All of the equipment types in the list are required by existing industry product standards to use a Type number marking.

Revision: 110.22. Identification of Disconnecting Means


Figure 11. Field labels are required for engineered series combinations of overcurrent protective devices

…. The marking shall be readily visible and state the following:
CAUTION — ENGINEERED SERIES COMBINATION
SYSTEM RATED _______ AMPERES. IDENTIFIED
REPLACEMENT COMPONENTS REQUIRED.

FPN: See 240.86(A) for interrupting rating marking for end-use equipment.

Analysis.Section 240.86 was revised in NEC-2005 to include an alternate method of applying a series rated combination of overcurrent devices that is selected under engineering supervision for existing installations. This alternative provided in 240.86(A) applies to existing installations only and provides a method to allow older existing electrical equipment to remain, where the overcurrent protection is coordinated and selected for the design and application by a licensed professional engineer engaged in the design and maintenance of electrical systems and installations. The primary differences between the requirements in 240.86(B) are that the series combinations covered by the requirements in 240.86(B) are listed and tested devices for use in series rated combinations. The alternative in 240.86(A) allows for a selected engineered design consisting of coordinated overcurrent protection that provides the required protection for equipment in such applications that meets the general requirements of 110.10. The revision to 110.22 incorporates a field-applied labeling requirement for existing equipment that is applied in an engineered series rated combination covered by 240.86(A) [see figure 11]. The new requirements for series rated combination systems labeling parallel the current field-marking rules for listed and tested series rated combinations. The key element of the label is that it includes the wording "engineered series rated combination” and the specific equipment requiring the labels will be as directed by the engineer responsible for the design under this alternative.

Revision: 110.26(C) Large Equipment

Analysis.Action by CMP-1 restores the dimension 1.8 m (6 ft) that applies to the equipment


Figure 12. Size and rating of the equipment are both factors in the requirement for two entrances and egress paths from the working space

rated at 1200 amperes or more that constitutes large equipment covered by this section. The requirement for physical size was removed during the 2005 NEC development process, which presented some challenges for meeting the requirements for two entrances and egress paths from some types of equipment where it was not practical or, in some cases, not possible. For example, a 1200-ampere panelboard that is 900 mm (3 ft) in width would be required to meet the two-entrance requirement as provided in NEC-2005. By restoring the requirement for physical size, building and engineering designs are less impacted by a requirement that is not necessary in all cases. This rule, in addition to many others, has to include minimum dimensions and energy levels that serve as a starting point regarding applicability. Large equipment with lower ampacity ratings, such as 800-ampere or 1000-ampere rated switchboards, and so forth, present similar challenges and safety concerns relative to whether two entrances or egress means are required (see figure 12). The second change inserts a specific distance from equipment at which a personnel door that provides access and egress from the working space must meet certain operational and physical characteristics. Personnel doors located less than 1.8 m (6 ft) from the working space mandated by this section will be required to swing away from the working space and be equipped with suitable hardware that operates under simple pressure as indicated in this requirement.

Revision: 110.33 Entrance to Enclosures and Access to Working Space
(A) Entrance. …. a personnel door(s) that is less than 3.7 m (12 ft) from the working space, the door(s) shall open in the direction of egress and be equipped with panic bars ….

(B) Access to Working Space. Permanent ladders or stairways shall be provided to give safe access to the working space around electric equipment installed on platforms, balconies, or mezzanine floors or in attic or roof rooms or spaces.

Analysis.This revision clarified which enclosures are covered by the requirements for entrance and egress means. The enclosures in 110.31, such as fenced areas, vaults, rooms, closets, and so forth, are required to meet the entrance and access requirements of this section. The new language in the second sentence of 110.33(A) clarifies that the personnel door(s) requirement applies to the working space and not necessarily the room in all cases. The 3.7 m (12 ft) distance is reasonable and provides for safe egress from the area. Currently, some jurisdictions are applying the requirement where the doors are a considerable distance from the working space, such as in large areas or rooms. These revisions should provide clear direction as to when the door is required to swing away from the working space, and when it must be equipped with simple release hardware. Personnel doors that are located 3.7 m (12 ft) or more from the working space mandated by this section will not be required to meet the physical and operational characteristics of this rule.

Chapter Two – Wiring and Protection

Article 210 Branch Circuits
New Section: 210.4(D) Grouping
(D) Grouping. The ungrounded and grounded conductors of each multiwire branch circuit shall be grouped by wire ties or similar means in at least one location within the panelboard or other point of origination.
Exception: The requirement for grouping shall not apply if the circuit enters from a cable or raceway unique to the circuit that makes the grouping obvious.

Analysis.This new section requires grouping the grounded conductor of multiwire branch


Figure 13. Multiwire branch-circuit conductors must be grouped at least once in enclosures such as panelboards or other equipment

circuits with the associated ungrounded conductors of the same multiwire branch circuit. These conductors must all be grouped together at least once at a location within the panelboard or equipment where the conductors of the circuit originate (see figure 13). This new grouping requirement should provide more ready means for workers and inspectors to identify the grounded conductor of a mutliwire branch circuit within the equipment where the circuit originates. The new exception to this rule relaxes this requirement where the entry of the circuit conductors of a cable or raceway makes the association obvious without additional grouping. Examples of installations qualifying under the exception include MC or AC cable assemblies or a raceway that contains only the conductors of the multiwire branch circuit. This change will result in all associated conductors of a multiwire branch circuit, including the grounded conductor, being physically grouped together at least once by wire ties or other means within the branch-circuit overcurrent device enclosure to allow for ease of visual recognition. Installers sometimes use wire ties to group multiple conductors of several branch circuits together while lacing and dressing the circuits in the equipment during the conductor termination process. This practice makes it difficult to identify which grounded (neutral) conductor is associated with the ungrounded conductors of the same multiwire branch circuit within the equipment. The new grouping rule should allow installers and inspectors to more readily identify multiwire branch-circuit conductors within the equipment where these conductors originate, enhancing safety.

Revision: 210.8(A) Dwelling Units
The two existing exceptions to 210.8(A)(2) have been deleted. Additional text added to 210.8(A)(5) indicates that any receptacles installed under the exceptions to 210.8(A)(5) shall not be considered as meeting the requirements of 210.52(G).

Analysis.The exception for receptacles that are not readily accessible has been deleted because the concept of being "readily accessible” is too vague and can lead to inconsistencies in how the requirements are applied. A garage door opener might not be readily accessible to short persons, but very well could be accessible to persons that are taller. The shock protection of this requirement should apply to all persons. Exception No. 2 has been deleted to establish consistency with the GFCI receptacle requirements in 210.8(A)(7) that were expanded in NEC-2005. The product safety standards for appliances covered by this exception require appliances to be manufactured with insulation dielectric leakage levels that do not exceed 0.5 mA. This level of leakage current is far below the 4–6 mA leakage thresholds of Class A ground-fault circuit interrupters manufactured to UL Standard 943. There clearly is no longer a need for either of these exceptions. Deleting the two exceptions creates consistency between the requirements in 210.8(A)(2) and 210.8(A)(7) and enhances the level of shock protection for persons where leakage levels in appliances could develop and present shock hazards that under the previous allowances of the exceptions would otherwise go undetected. Protection by ground-fault circuit interrupters is not related to the location of the receptacle. If cord- and plug-connected utilization equipment (appliances exempted by the previous exceptions) has abnormal or excessive leakage current levels that will trip the GFCI, protection should be provided. Based on the information in the applicable product safety standards, the maximum leakage current for typical cord- and plug-connected equipment (appliances) is 0.5 mA. The trip range for Class A GFCI protective devices is 4–6 mA. In order for this utilization equipment to trip a GFCI protective device, leakage current levels would have to reach 8 to 12 times that permitted by the product standard, creating safety concerns. The fact that the receptacle is not readily accessible will have no impact on the shock hazard protection for persons encountering the utilization equipment.

Revision: 210.12(B) Dwelling Units

Analysis.These revisions simply expand the requirements for arc-fault circuit interrupter


Figure 14. All 15- and 20-ampere branch circuits in dwelling units are required to be protected by arc-fault circuit interrupter protection.

protection to all 15- and 20-ampere branch circuits installed in dwelling units (see figure 14). CMP-2 expanded the AFCI protection requirements to branch-circuit outlets that supply dwelling unit bedrooms in NEC-2005 as a means to enhance safety and gain experience putting the application in an easily defined and limited area. Arc-fault circuit interrupters have been proven effective in detecting and clearing arcing conditions or events in wiring systems before damage and loss could occur. This is the principle objective of this type of protection. Experience has shown that AFCI protective devices also detect numerous wiring errors and, in addition, they have found wiring damage and equipment damage that could have been potential sources of fire where protected only by conventional protection devices. A strong basis for limiting this protection to circuits that supply only dwelling unit bedrooms no longer exists, and the increased protection is needed for other circuits. This expansion will continue the effort to help reduce and minimize fires of electrical origin in dwellings. The second paragraph has been deleted because the effective date for ACFI protective devices coincides with the publication of NEC-2008 and so is no longer necessary. Proposed deadline extensions were rejected by CMP-2, which affirms the panel’s intentions that all AFCI protective devices be combination types as of January 1, 2008.

Revision: 210.62 Show Windows


Figure 15

Analysis. More specific location criteria that must be applied to show window receptacle installations are imposed. The new rule requires the receptacle to be located within 450 mm (18 in.) of the top of any show window (see figure 15). This change provides clear direction on how to meet the placement criteria for show window receptacles, while at the same time providing enforcement with a means to apply the rule more consistently to all show windows. This results in receptacles being located for the convenient and practical use for which they were intended, without having to resort to extension cord use, or other remedial means of supplying power for show window applications that can lead to or result in less than safe conditions.

Article 215 Feeders
Revision: 215.10 Exception No. 3

The provisions of this section shall not apply if ground-fault protection of equipment is provided on the supply side of the feeder and on the load side of any transformer supplying the feeder.

Analysis.The revisions to Exception No. 3 clarify where GFPE is required (see figure 16). The


Figure 16

intent is not to require GFPE on a feeder disconnect if that feeder has GFPE protection provided upstream. However, some are misinterpreting that GFPE could be provided on the primary of a transformer to meet this exception. Of course, GFPE on the primary side of a transformer provides no equipment protection to equipment connected to the secondary since the ground-fault on the secondary only returns current to the secondary of the transformer. The objective is to allow relaxing the GFPE requirement for distribution equipment connected to feeders where a GFPE device is supplied upstream of the feeder, at the service equipment for example. When a transformer is inserted in a feeder, essentially this is a new derived system or source. The requirement for ground-fault protection for equipment is related to the size of the equipment supplied by the feeder as indicated in the rule that this exception follows. Current, including ground-fault current, will always try to return to the source. In this case, the source is the transformer. The GFPE on the supply side of such transformers would not function to protect the equipment in accordance with the requirements of this rule because the ground-fault current would not be attempting to return to the service and utility transformer but to the transformer on the supply side of the feeder. This exception does not apply to field installations where the feeder is derived from a transformer supplied from the service equipment on its supply side. Any GFPE on the supply side used to exempt the feeder disconnect from GFPE must be on the load side of the transformer supplying the feeder.

Article 225 Outside Branch Circuits and Feeders
Revision: 225.39 Rating of Disconnect

Analysis.Sections 225.31 and 225.33 address requirements for disconnecting means in feeders


Figure 17

supplying separate buildings or structures, which are similar to those required for service disconnecting means covered in 230.70 and 230.71. Section 230.80 includes methods of establishing a combined rating for installations where multiple disconnects in separate enclosures are used as the service disconnecting means. Disconnecting means is defined in Article 100 and can be a single disconnect or a group of disconnects. Section 225.39 has been revised by adding a new second sentence to clarify that when more that one switch or circuit breaker is used as the disconnecting means for a feeder supplying a separate building or structure, the combined ratings of the switches or circuit breakers used as the service disconnecting means can be added together to achieve the minimum rating required for the disconnecting means (see figure 17). This revision incorporates methods of establishing combined ratings of several disconnects in 225.39 that are similar to the requirements already provided in 230.80 for services.

Article 230 Services
Revision: 230.44, Exception

Analysis.This revision includes specific labeling requirements that clearly indicate where the


Figure 18

cable tray is being used for service-entrance conductors (see figure 18). The last two sentences were added to ensure that the cable tray containing a barrier separating the service-entrance conductors are clearly identified from feeders and branch circuits installed in the other side of the cable tray. The labels should be visible after the installation of the cable tray since an installer may not be able to differentiate between section/partition of the tray containing the service-entrance conductors and inadvertently install protected conductors with unprotected conductors. Cable trays shall be identified with permanently affixed labels with the wording "Service-Entrance Conductors.”

Revision: 230.79 Rating of Service Disconnect
The service disconnecting means shall have a rating not less than the calculated load to be carried, determined in accordance with Parts III and IV of Article 220.

Analysis.These revisions clarify that the rating of the service disconnect is to be not less that the


Figure 19

calculated load to be carried and not the actual load carried (see figure 19). This revision logically recognizes that the load to be carried can vary from time to time, but a calculated load is the maximum anticipated load the disconnect would need to be capable of handling. The word "calculated” was used to be consistent with the changes in the text in Article 220 and other parts of NEC-2005 where the word "computed” was formerly used. The words "Parts III and VI” were added to be consistent with the NEC Style Manual and to identify the applicable parts of Article 220 to which this section refers.

IAEI’s Analysis of Changes book is all about providing valuable insight as to how the revisions have affected the Code text. Another real important element of reviewing each change and understanding its impact is the analysis through clear and concise language understandable to all Code users. This article is an effort to provide readers with current information about revisions that have been accepted by the technical committees at this stage in the NEC development process. Part II of this article will be in the next issue of the IAEI News and include additional significant proposed changes for NEC-2008.


 

About Michael Johnston: Michael Johnston is NECA’s executive director of standards and safety. Prior to working with NECA, Mike worked for the International Association of Electrical Inspectors as the director of education, codes and standards. Mike is a member of the IBEW and has experience as an electrical journeyman wireman, foreman and project superintendant. Mike achieved all electrical inspector certifications through IAEI and ICC and has worked as an electrical inspector and electrical inspection field supervisor for the city of Phoenix, AZ. Mike achieved a B.S. in business management from the University of Phoenix. Mike is the chairman of the NEC Correlating Committee and served on NEC CMP-5 in the 2002, 2005, 2008, and chair of CMP-5 representing NECA for the 2011 NEC cycle. Johnston is an active member of ANSI, IAEI, NFPA, ASSE, the NFPA Electrical Section, Education Section, the UL Electrical Council, and National Safety Council.

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Analysis of Changes, Part 1, NEC-2008

Posted By Michael Johnston , Saturday, July 01, 2006
Updated: Sunday, February 10, 2013

Revisions to the NEC are inevitable, and given the unique and important nature of this electrical safety standard, very necessary. The NEC development process is ever dynamic and ongoing, because new technologies are continuously entering the electrical market and code rules must be developed or revised to address electrical safety concerns related to these new materials, equipment, emerging methods or technologies. There were 3,688 proposals, including all technical committee proposals, to change NEC-2008. These proposed changes were acted on by the technical committees at the Report on Proposals (ROP) meetings held in January 2006. This article provides an overview based on code-making panel actions taken on the proposals in the first stage of the development process.

These changes could be affected by subsequent CMP actions on public comments to the proposed revisions.

NFPA’s Report on Proposals includes all proposed changes and related technical committee actions and statements, and is published for public review and comment. Public comments to proposed changes are due to NFPA by October 20, 2006 (5:00 P.M. EST). The development process is an open consensus process in which involvement by everyone is encouraged. Forms for submitting comments are provided on the NFPA website and in the back of the Report on Proposals.

This article is Part I of a series that visits some of the more significant revisions proposed and accepted for NEC-2008.

Code-Wide Revisions

A few revisions were accepted that affect the entire NEC. Three such changes include (1) procedural changes in how the definitions of words and terms are handled by the technical committees, (2) grounding and bonding definitions and terminology revisions, and (3) two new definitions of the terms neutral conductor and neutral point.

Change in Procedures
The NEC-2008 development process included a shift in responsibility for any technical definitions that fall under the scope of responsibility of certain NEC technical committees. Traditionally all of the definitions in Article 100 were the responsibility of code-making panel 1. Action by the NEC Technical Correlating Committee (TCC) results in each code-making panel being responsible for definitions of words and terms that are under its responsibility, but these definitions will continue to be located in Article 100. Definitions that are general in nature will continue to be assigned to code-making panel 1. This change will result in more accurately defined words and consistent correlation of terms throughout the NEC.

Grounding and Bonding
Terms and Rules

A task group was assembled to explore several significant issues regarding grounding and bonding terminology used the Code. The definitions affected by the work of the task group are as follows:

Bonding (Bonded)– revised
Grounding Electrode Conductor– revised
Grounding Conductor, Equipment– revised
Grounding Electrode– revised
Ground– revised
Grounding (Grounded)– revised
Grounded, Effectively– deleted
Ungrounded– new

Where revisions were necessary, the task group developed and submitted proposals to each NEC technical committee. In many cases, revisions provided specific direction for users. The changes in one instance resulted in changing the term shall be grounded to the wording "shall be connected to an equipment grounded conductor” where that was the original intention of the requirement.

The definition of effectively grounded was deleted because the term is subjective and has no specific parameters for making determinations as to whether or not something is effectively grounded. Instances where it was used in previous editions of the Code have been revised to remove the word "effectively” from the phrase.

New Definitions of Neutral Conductor and Neutral Point


Figure 1. Neutral conductor and neutral point are defined

These definitions have been incorporated into Article 100 to differentiate between a neutral conductor of a system and a neutral point (termination point for neutral conductors) within NEC rules where the terms are used (see figure 1).

Aneutral conductor is intended to carry current under normal operation. In power systems, the neutral conductors are typically the grounded conductor, but not all grounded conductors are neutral conductors.

Aneutral point relates to a common connection point for a neutral conductor connection at the source or system windings.

The rules throughout the NEC that include the word "neutral” have been clarified to be specific to either the neutral conductor or the neutral point of a supply system.

Chapter One – General

Article 100 Definitions


Figure 2. Example of bundled cables

Several definitions in Article 100 have been revised, and a few new definitions have been added.

Bundled.Cables or conductors that are physically tied, wrapped, taped or otherwise periodically bound together. [Relocated from 520.2 to Article 100, see figure 2]

Clothes Closet.A non-habitable room or space intended primarily for storage of garments and apparel. [New definition, see figure 3]

Equipotential Plane.An area where mesh or other conductive elements are embedded in or


Figure 3. Clothes closet


Figure 4. Handhole enclosure defined

placed under concrete or other conductive surface, are bonded together and to all metal structures and fixed nonelectrical equipment that may become energized, and are connected to the electrical grounding system. [Incorporates two concepts into one common term]

Handhole Enclosure.An enclosure for use in underground systems, provided with an open or closed bottom, and sized to allow personnel to reach into, but not enter, for the purpose of installing, operating, or maintaining equipment or wiring or both. [Requirement of identification removed from definition, see figure 4]

 


Figure 5. Kitchen defined

Kitchen.

An area with a sink and permanent facilities for food preparation and cooking [New definition, see figure 5]

Neutral Conductor. The conductor connected to the neutral point of a system that is intended to carry current under normal conditions. [New definition, see figure 6]

Neutral point. The common point on a wye-connection in a polyphase system or midpoint on a single-phase, 3-wire system, or midpoint of a single-phase portion of a 3-phase delta system, or a midpoint of a 3-wire, direct current system [New definition, see figure 7]


Figure 6. Neutral conductor of a system

FPN: At the neutral point of the system, the vectorial sum of the nominal voltages from all other phases within the system that utilize the neutral, with respect to the neutral point, is zero potential.

Qualified Person.One who has skills and knowledge related to the construction and operation of the electrical equipment and installations and has received safety training to recognize and avoid the hazards involved. [Revised definition, see figure 8]

Article 110 Requirements for Electrical Installations
Revision: 110.16 Flash Protection


Figure 7. Neutral point of a system

Electrical equipment such as… shall be field marked to warn qualified persons of potential electric arc flash hazards.

Analysis.Two changes to 110.16 provide additional clarity and allow for more appropriate and consistent application to field installations that qualify for the warning labels required by this section. The first revision broadens the requirement by including all types of equipment that would qualify for the field-applied arc-flash warning labels (see figure 9). Previous requirements of this section were limited only to the types of equipment actually identified in the rule. By including the words, "equipment such as” the concept of applicability is expanded to all equipment types that are likely to require examination, adjustment, servicing, or maintenance while energized. This requirement applies to items such as enclosed circuit breakers, some transformers, and other equipment not specifically included in the previous text. The second revision places a specific limitation on the types of dwelling


Figure 8. Qualified persons

occupancies covered by these label requirements for equipment. Multiple occupancy dwelling structures such as those in apartment complexes and so forth, where the service equipment and other equipment can be large, definitely qualify for the arc-flash warning labels. The arc-flash warning label requirements do not apply to one- and two-family dwelling units, but arc flash hazards are present in those installations and electrical safety work practices should be followed regardless of the type of occupancy in which the equipment is installed. This rule only addresses where field-applied arc flash warning labels are required. The fine print notes have not been affected by these changes, and still provide appropriate references to other applicable standards that provide relative information about


Figure 9. Arc-flash warning label requriements

safe work practices and guidelines for designing safety signs and labels for equipment.

New Section: 110.20 Enclosure Types
Enclosures …shall be marked with an Enclosure Type number as shown in Table 110.20.

Analysis.Concepts introduced during the 2005 NEC development process cycle ultimately led to creating a new Section 110.20 and relocating existing Table 430.91, which includes enclosure type designations and information about their use, to this section (see figure 10). The information within the relocated table remains essentially the same. The table is now identified as Table 110.20. Electrical enclosures in addition to the enclosures used for motor applications as covered by Article 430 are also required to be suitable for the environment in which they are


Figure 10. Enclosure types

installed. The effect of this change provides consistency between the UL General Information for Electrical Equipment Directory (White Book) category (AALZ) and the NEC, which apply generally to all electrical equipment, not just equipment associated with motor installations covered by Article 430. Relocating requirements of 430.91 and Table 430.91 into general application Article 110 and specifically indicating the types of equipment to which the requirements apply add clarity. All of the equipment types in the list are required by existing industry product standards to use a Type number marking.

Revision: 110.22. Identification of Disconnecting Means


Figure 11. Field labels are required for engineered series combinations of overcurrent protective devices

…. The marking shall be readily visible and state the following:
CAUTION — ENGINEERED SERIES COMBINATION
SYSTEM RATED _______ AMPERES. IDENTIFIED
REPLACEMENT COMPONENTS REQUIRED.

FPN: See 240.86(A) for interrupting rating marking for end-use equipment.

Analysis.Section 240.86 was revised in NEC-2005 to include an alternate method of applying a series rated combination of overcurrent devices that is selected under engineering supervision for existing installations. This alternative provided in 240.86(A) applies to existing installations only and provides a method to allow older existing electrical equipment to remain, where the overcurrent protection is coordinated and selected for the design and application by a licensed professional engineer engaged in the design and maintenance of electrical systems and installations. The primary differences between the requirements in 240.86(B) are that the series combinations covered by the requirements in 240.86(B) are listed and tested devices for use in series rated combinations. The alternative in 240.86(A) allows for a selected engineered design consisting of coordinated overcurrent protection that provides the required protection for equipment in such applications that meets the general requirements of 110.10. The revision to 110.22 incorporates a field-applied labeling requirement for existing equipment that is applied in an engineered series rated combination covered by 240.86(A) [see figure 11]. The new requirements for series rated combination systems labeling parallel the current field-marking rules for listed and tested series rated combinations. The key element of the label is that it includes the wording "engineered series rated combination” and the specific equipment requiring the labels will be as directed by the engineer responsible for the design under this alternative.

Revision: 110.26(C) Large Equipment

Analysis.Action by CMP-1 restores the dimension 1.8 m (6 ft) that applies to the equipment


Figure 12. Size and rating of the equipment are both factors in the requirement for two entrances and egress paths from the working space

rated at 1200 amperes or more that constitutes large equipment covered by this section. The requirement for physical size was removed during the 2005 NEC development process, which presented some challenges for meeting the requirements for two entrances and egress paths from some types of equipment where it was not practical or, in some cases, not possible. For example, a 1200-ampere panelboard that is 900 mm (3 ft) in width would be required to meet the two-entrance requirement as provided in NEC-2005. By restoring the requirement for physical size, building and engineering designs are less impacted by a requirement that is not necessary in all cases. This rule, in addition to many others, has to include minimum dimensions and energy levels that serve as a starting point regarding applicability. Large equipment with lower ampacity ratings, such as 800-ampere or 1000-ampere rated switchboards, and so forth, present similar challenges and safety concerns relative to whether two entrances or egress means are required (see figure 12). The second change inserts a specific distance from equipment at which a personnel door that provides access and egress from the working space must meet certain operational and physical characteristics. Personnel doors located less than 1.8 m (6 ft) from the working space mandated by this section will be required to swing away from the working space and be equipped with suitable hardware that operates under simple pressure as indicated in this requirement.

Revision: 110.33 Entrance to Enclosures and Access to Working Space
(A) Entrance. …. a personnel door(s) that is less than 3.7 m (12 ft) from the working space, the door(s) shall open in the direction of egress and be equipped with panic bars ….

(B) Access to Working Space. Permanent ladders or stairways shall be provided to give safe access to the working space around electric equipment installed on platforms, balconies, or mezzanine floors or in attic or roof rooms or spaces.

Analysis.This revision clarified which enclosures are covered by the requirements for entrance and egress means. The enclosures in 110.31, such as fenced areas, vaults, rooms, closets, and so forth, are required to meet the entrance and access requirements of this section. The new language in the second sentence of 110.33(A) clarifies that the personnel door(s) requirement applies to the working space and not necessarily the room in all cases. The 3.7 m (12 ft) distance is reasonable and provides for safe egress from the area. Currently, some jurisdictions are applying the requirement where the doors are a considerable distance from the working space, such as in large areas or rooms. These revisions should provide clear direction as to when the door is required to swing away from the working space, and when it must be equipped with simple release hardware. Personnel doors that are located 3.7 m (12 ft) or more from the working space mandated by this section will not be required to meet the physical and operational characteristics of this rule.

Chapter Two – Wiring and Protection

Article 210 Branch Circuits
New Section: 210.4(D) Grouping
(D) Grouping. The ungrounded and grounded conductors of each multiwire branch circuit shall be grouped by wire ties or similar means in at least one location within the panelboard or other point of origination.
Exception: The requirement for grouping shall not apply if the circuit enters from a cable or raceway unique to the circuit that makes the grouping obvious.

Analysis.This new section requires grouping the grounded conductor of multiwire branch


Figure 13. Multiwire branch-circuit conductors must be grouped at least once in enclosures such as panelboards or other equipment

circuits with the associated ungrounded conductors of the same multiwire branch circuit. These conductors must all be grouped together at least once at a location within the panelboard or equipment where the conductors of the circuit originate (see figure 13). This new grouping requirement should provide more ready means for workers and inspectors to identify the grounded conductor of a mutliwire branch circuit within the equipment where the circuit originates. The new exception to this rule relaxes this requirement where the entry of the circuit conductors of a cable or raceway makes the association obvious without additional grouping. Examples of installations qualifying under the exception include MC or AC cable assemblies or a raceway that contains only the conductors of the multiwire branch circuit. This change will result in all associated conductors of a multiwire branch circuit, including the grounded conductor, being physically grouped together at least once by wire ties or other means within the branch-circuit overcurrent device enclosure to allow for ease of visual recognition. Installers sometimes use wire ties to group multiple conductors of several branch circuits together while lacing and dressing the circuits in the equipment during the conductor termination process. This practice makes it difficult to identify which grounded (neutral) conductor is associated with the ungrounded conductors of the same multiwire branch circuit within the equipment. The new grouping rule should allow installers and inspectors to more readily identify multiwire branch-circuit conductors within the equipment where these conductors originate, enhancing safety.

Revision: 210.8(A) Dwelling Units
The two existing exceptions to 210.8(A)(2) have been deleted. Additional text added to 210.8(A)(5) indicates that any receptacles installed under the exceptions to 210.8(A)(5) shall not be considered as meeting the requirements of 210.52(G).

Analysis.The exception for receptacles that are not readily accessible has been deleted because the concept of being "readily accessible” is too vague and can lead to inconsistencies in how the requirements are applied. A garage door opener might not be readily accessible to short persons, but very well could be accessible to persons that are taller. The shock protection of this requirement should apply to all persons. Exception No. 2 has been deleted to establish consistency with the GFCI receptacle requirements in 210.8(A)(7) that were expanded in NEC-2005. The product safety standards for appliances covered by this exception require appliances to be manufactured with insulation dielectric leakage levels that do not exceed 0.5 mA. This level of leakage current is far below the 4–6 mA leakage thresholds of Class A ground-fault circuit interrupters manufactured to UL Standard 943. There clearly is no longer a need for either of these exceptions. Deleting the two exceptions creates consistency between the requirements in 210.8(A)(2) and 210.8(A)(7) and enhances the level of shock protection for persons where leakage levels in appliances could develop and present shock hazards that under the previous allowances of the exceptions would otherwise go undetected. Protection by ground-fault circuit interrupters is not related to the location of the receptacle. If cord- and plug-connected utilization equipment (appliances exempted by the previous exceptions) has abnormal or excessive leakage current levels that will trip the GFCI, protection should be provided. Based on the information in the applicable product safety standards, the maximum leakage current for typical cord- and plug-connected equipment (appliances) is 0.5 mA. The trip range for Class A GFCI protective devices is 4–6 mA. In order for this utilization equipment to trip a GFCI protective device, leakage current levels would have to reach 8 to 12 times that permitted by the product standard, creating safety concerns. The fact that the receptacle is not readily accessible will have no impact on the shock hazard protection for persons encountering the utilization equipment.

Revision: 210.12(B) Dwelling Units

Analysis.These revisions simply expand the requirements for arc-fault circuit interrupter


Figure 14. All 15- and 20-ampere branch circuits in dwelling units are required to be protected by arc-fault circuit interrupter protection.

protection to all 15- and 20-ampere branch circuits installed in dwelling units (see figure 14). CMP-2 expanded the AFCI protection requirements to branch-circuit outlets that supply dwelling unit bedrooms in NEC-2005 as a means to enhance safety and gain experience putting the application in an easily defined and limited area. Arc-fault circuit interrupters have been proven effective in detecting and clearing arcing conditions or events in wiring systems before damage and loss could occur. This is the principle objective of this type of protection. Experience has shown that AFCI protective devices also detect numerous wiring errors and, in addition, they have found wiring damage and equipment damage that could have been potential sources of fire where protected only by conventional protection devices. A strong basis for limiting this protection to circuits that supply only dwelling unit bedrooms no longer exists, and the increased protection is needed for other circuits. This expansion will continue the effort to help reduce and minimize fires of electrical origin in dwellings. The second paragraph has been deleted because the effective date for ACFI protective devices coincides with the publication of NEC-2008 and so is no longer necessary. Proposed deadline extensions were rejected by CMP-2, which affirms the panel’s intentions that all AFCI protective devices be combination types as of January 1, 2008.

Revision: 210.62 Show Windows


Figure 15

Analysis. More specific location criteria that must be applied to show window receptacle installations are imposed. The new rule requires the receptacle to be located within 450 mm (18 in.) of the top of any show window (see figure 15). This change provides clear direction on how to meet the placement criteria for show window receptacles, while at the same time providing enforcement with a means to apply the rule more consistently to all show windows. This results in receptacles being located for the convenient and practical use for which they were intended, without having to resort to extension cord use, or other remedial means of supplying power for show window applications that can lead to or result in less than safe conditions.

Article 215 Feeders
Revision: 215.10 Exception No. 3

The provisions of this section shall not apply if ground-fault protection of equipment is provided on the supply side of the feeder and on the load side of any transformer supplying the feeder.

Analysis.The revisions to Exception No. 3 clarify where GFPE is required (see figure 16). The


Figure 16

intent is not to require GFPE on a feeder disconnect if that feeder has GFPE protection provided upstream. However, some are misinterpreting that GFPE could be provided on the primary of a transformer to meet this exception. Of course, GFPE on the primary side of a transformer provides no equipment protection to equipment connected to the secondary since the ground-fault on the secondary only returns current to the secondary of the transformer. The objective is to allow relaxing the GFPE requirement for distribution equipment connected to feeders where a GFPE device is supplied upstream of the feeder, at the service equipment for example. When a transformer is inserted in a feeder, essentially this is a new derived system or source. The requirement for ground-fault protection for equipment is related to the size of the equipment supplied by the feeder as indicated in the rule that this exception follows. Current, including ground-fault current, will always try to return to the source. In this case, the source is the transformer. The GFPE on the supply side of such transformers would not function to protect the equipment in accordance with the requirements of this rule because the ground-fault current would not be attempting to return to the service and utility transformer but to the transformer on the supply side of the feeder. This exception does not apply to field installations where the feeder is derived from a transformer supplied from the service equipment on its supply side. Any GFPE on the supply side used to exempt the feeder disconnect from GFPE must be on the load side of the transformer supplying the feeder.

Article 225 Outside Branch Circuits and Feeders
Revision: 225.39 Rating of Disconnect

Analysis.Sections 225.31 and 225.33 address requirements for disconnecting means in feeders


Figure 17

supplying separate buildings or structures, which are similar to those required for service disconnecting means covered in 230.70 and 230.71. Section 230.80 includes methods of establishing a combined rating for installations where multiple disconnects in separate enclosures are used as the service disconnecting means. Disconnecting means is defined in Article 100 and can be a single disconnect or a group of disconnects. Section 225.39 has been revised by adding a new second sentence to clarify that when more that one switch or circuit breaker is used as the disconnecting means for a feeder supplying a separate building or structure, the combined ratings of the switches or circuit breakers used as the service disconnecting means can be added together to achieve the minimum rating required for the disconnecting means (see figure 17). This revision incorporates methods of establishing combined ratings of several disconnects in 225.39 that are similar to the requirements already provided in 230.80 for services.

Article 230 Services
Revision: 230.44, Exception

Analysis.This revision includes specific labeling requirements that clearly indicate where the


Figure 18

cable tray is being used for service-entrance conductors (see figure 18). The last two sentences were added to ensure that the cable tray containing a barrier separating the service-entrance conductors are clearly identified from feeders and branch circuits installed in the other side of the cable tray. The labels should be visible after the installation of the cable tray since an installer may not be able to differentiate between section/partition of the tray containing the service-entrance conductors and inadvertently install protected conductors with unprotected conductors. Cable trays shall be identified with permanently affixed labels with the wording "Service-Entrance Conductors.”

Revision: 230.79 Rating of Service Disconnect
The service disconnecting means shall have a rating not less than the calculated load to be carried, determined in accordance with Parts III and IV of Article 220.

Analysis.These revisions clarify that the rating of the service disconnect is to be not less that the


Figure 19

calculated load to be carried and not the actual load carried (see figure 19). This revision logically recognizes that the load to be carried can vary from time to time, but a calculated load is the maximum anticipated load the disconnect would need to be capable of handling. The word "calculated” was used to be consistent with the changes in the text in Article 220 and other parts of NEC-2005 where the word "computed” was formerly used. The words "Parts III and VI” were added to be consistent with the NEC Style Manual and to identify the applicable parts of Article 220 to which this section refers.

IAEI’s Analysis of Changes book is all about providing valuable insight as to how the revisions have affected the Code text. Another real important element of reviewing each change and understanding its impact is the analysis through clear and concise language understandable to all Code users. This article is an effort to provide readers with current information about revisions that have been accepted by the technical committees at this stage in the NEC development process. Part II of this article will be in the next issue of the IAEI News and include additional significant proposed changes for NEC-2008.


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Emergency Lighting and Exit Signs Application and Installation Requirements

Posted By Ark Tsisserev, Saturday, July 01, 2006
Updated: Monday, February 11, 2013

Application of certain types of electrical equipment may be governed by codes other than the Canadian Electrical Code (CEC). Emergency lighting and exit signs are good examples of such types of equipment.

In fact, the scope of Section 46 of the CEC, Part I states that this section applies to installation, operation and maintenance of emergency lighting and exits signs that are required by the National Building Code of Canada (NBCC). Although the scope of Section 46 covers other types of emergency equipment and systems, this article concentrates only on emergency lighting and exits signs. It is important to note that even if the emergency lighting and exit signs are not necessarily required by the NBCC, inspectors’ viewpoint is that if this equipment is installed it must comply with the installation requirements of the CEC (bonding, wiring methods, selection of the overcurrent protection, conductors sizes, etc.).

However, before we will analyze provisions of Section 46 for installation and operation of the emergency lighting and exit signs, it is beneficial to visit applicable sections of the NBCC that regulate application requirements for this electrically connected life and fire safety equipment.

Emergency Lighting

Let’s start with the emergency lighting. Article 3.2.7.3 of the NBCC mandates that the emergency lighting must be provided in the following areas:

  1. exits,
  2. principal routes that constitute access to exits in an open floor area,
  3. corridors used by the public,
  4. corridors serving patients’ sleeping rooms,
  5. corridors serving classrooms,
  6. underground walkways,
  7. public corridors,
  8. floor areas or parts of such floor areas where public may congregate in
    a) theatres, movie houses and similar occupancies, where house lights are turned off or dimmed during a performance or
    b) schools, assembly halls, churches, restaurants, meeting rooms, arenas and other such similar occupancies, if such occupancies have occupant load of 60 or more persons.
    This information is essential to the designers of emergency lighting. It allows them to understand with a full certainty, where the emergency lighting must be installed. The NBCC also prescribes when such emergency lighting must be actuated, how it must perform and what power source must be used for the emergency lighting systems and equipment.

Article 3.2.7.4 of the NBCC states that an emergency power supply must be provided from a power source such as batteries or generators to maintain emergency lighting in each area listed in Article 3.2.7.3 when the normal power supply to that area is interrupted. The NBCC also mandates that the emergency power supply must be designed and installed so that it is: a) automatically actuated upon failure of the regular power and b) capable to perform for at least 30 minutes in each required area.
In a building that is classified as a hospital or a jail, the emergency lighting must function at least for an hour; and if the building is classified as a high building, then the emergency lighting must operate for at least 2h.

It is important to note that terms exit, floor area, and public corridors used in Article 3.2.7.3 are defined in the NBCC, and that the designers of emergency lighting must be cognizant on the extent of these definitions. For example, "Exit means that part of a means of egress, including doorways, that leads from the floor area it serves, to a separate building, an open public thoroughfare, or an exterior open space protected from fire exposure from the building and having access to an open public thoroughfare”.

Why is this definition important to the electrical designers and contractors? Because it will help them to understand that depending on the building design, an exit can include outside open spaces which will also require provisions for normal and emergency lighting. Therefore, electrical designers and contractors must consult with the building code practitioners to establish the boundaries of the exits in each specific project. This approach will assist them to identify accurately the areas where emergency lighting systems and equipment must be installed under requirements of section 46 of the CEC.

Now, we are in a familiar territory. Rules of Section 46 will have to be followed for installation of emergency lighting systems (Rule 46-200) and unit equipment (Rule 46-300), and for wiring methods (Rule 46-108).

Exit Signs

Let’s now look at exit signs. Article 3.4.5.1. (2) of the NBCC mandates that every exit sign shall be illuminated continuously while the building is occupied. The NBCC considers two types of illuminated signs: internally illuminated (i.e., an exit sign is in essence a luminaire), and externally illuminated, when illumination of an exit sign is provided by normal or emergency lighting in the area where such exit sign is installed. Thus, regardless whether illumination of an exit sign is provided by an electrical circuit directly supplying this sign (internally illuminated) or by electrical circuits supplying lighting in the area where an exit sign is installed (externally illuminated), such exit sign must be illuminated continuously. This means that the emergency power for emergency lighting as discussed earlier, must be provided for illumination of an exit sign.

The NBCC also lists mandatory locations for exit signs.

Article 3.4.5.1 states that an exit sign must be placed over or adjacent to every exit door in a building more than 2 storeys in building height, in a building with occupant load more than 150 persons, in a room or floor area that has a fire escape as part of a required means of egress. In addition every egress door from rooms with occupant load more than 60 persons in occupancies such as theatres, movie houses, restaurants, dancing halls, licensed beverage establishments, etc., must be provided with an exit sign—for easy identification of the egress doorway.

Building code experts should be also consulted by the electrical designers and installers in order to identify accurately required locations for installation of electrically connected exit signs. And when this is done, Rule 46-400 of the CEC will guide the designers and contractors towards installation requirements and wiring methods.

It is interesting to note that Appendix G of the CEC provides a comprehensive cross-reference from Rules of Sections 46 to the applicable articles of the NBCC.

And as it is usually done in cases where life safety equipment and systems mandated by the NBCC and the CEC are intended for installation—authorities with jurisdictional power for application and installation of emergency lighting and exit signs must be consulted when these installations take place.


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Be All You Can Be! Come to your section meeting

Posted By James W. Carpenter, Saturday, July 01, 2006
Updated: Monday, February 11, 2013

It is the middle of the summer and fall is just around the corner. Likewise, IAEI’s annual section meetings are approaching. This issue of the IAEI News highlights the six section meeting locations and programs. I always get excited about now, looking forward to traveling to all the great locations that have been selected to hold these meetings. Cities like Spokane, Washington; Traverse City, Michigan; Ottawa, Canada; Philadelphia, Pennsylvania; Fort Worth, Texas; and San Diego, California are where we are scheduled to go this year. Meeting new people, getting reacquainted with friends, and sharing all the many things that we have experienced in the past year is always exciting. What a wonderful opportunity to get together.

The leaders that have accepted the responsibility of putting in long hours planning and arranging for these annual meetings deserve more than just a round of applause. They have not only selected great places and made all the arrangements but also have planned for outstanding educational opportunities. Many events in which the attendees can increase their knowledge and skills are being made available. With all this hard work by these leaders, shouldn’t you be at your section meeting? Take advantage of the opportunities and network with your peers.

I have used the word "leaders” several times so far. IAEI is blessed with the many volunteers that step up and share their abilities, knowledge, and expertise. All of us, even the newest member, have experiences to share and that is what makes this time of section meetings so exciting and important. This world of ours is now global, no longer is it just our little corner of the city, town, or county where we live. What happens on the other side of the globe now affects use directly—have you bought gas lately? We must stay current, connected, marketable, and associated to be able to serve our neighborhood and help assure that our homes, workplaces, and play places are as safe as can be when we use electricity. Plan now to attend your section meeting. Learn from others, teach others, become a leader, and above all participate in the IAEI.

The National Electrical Code is in the part of its cycle where the proposals to change some of the requirements were considered by the code-making panels during the meeting in January 2006 and are now open for comment. Attending your section meeting provides an excellent opportunity for you to participate in the comment phase of the code-making process. During the section meetings is where IAEI’s position will be developed. Each section has procedures for getting a chapter’s, division’s, or an individual’s proposed comment on the agenda for discussion. The comments developed then will be forwarded to the International Code Clearing Committee for consideration as an official IAEI comment to the NEC process.

The NEC is not the only code revision process going on this year. The 2006 edition of the Canadian Electrical Code (CE Code) has just been published. The revision cycle has already begun as the CE Code Part 1 Committee met in June 2006. The Canadian Section meeting will afford an opportunity to learn about the 2006 CE Code as well as participate in the revision process for the next edition.

This issue of the News contains the first installment of some of the more significant proposals acted upon by the NEC code-making panels. Mike Johnston has compiled a list along with analyses of the changes that were identified by IAEI’s representatives on all twenty code-making panels. Ark Tsisserev, chairman of the technical committee on the Canadian Electrical Code, also provides insight on the CE Code in his Inspectors’ Corner.

I recently read an article written by an ex-electrical inspector who is now with an electrical contractors association. Some of his comments were distributing to me, but he made some good points. One was that it is the responsibility of the electrical inspector to be well educated in the Code. How true! How can we enforcers of the codes demand the respect of not just the installer but also the public we serve if we are not well-versed and familiar with the codes we are charged with enforcing? Likewise, the policy makers and public officials of the jurisdiction where we work and live must also be educated on the importance of good inspections and inspectors. They need to be made aware of the importance of sending their inspectors to seminars, workshops, and chapter and section meetings to further their knowledge and skills.

Don’t let the summer workload prevent you from making plans to attend your annual section meeting. Along with the many fun things available in the various locations, many events will provide education, training and the opportunity to develop your leadership skills. After all, we all are leaders in some way. So, Be All You Can Be! Come to your section meeting.


Read more by James W. Carpenter

Tags:  Editorial  July-August 2006 

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