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IAEI News provides educational forums, updates on electrical codes and reports of innovative research to facilitate the development and enforcement of practices designed to drive efficiency and compliance with the highest standards of product development and safety—for the public as well as for electrical personnel. The magazine reaches authorities with power of product specification, approval and acceptance. Published six times a year by the International Association of Electrical Inspectors.

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Critical Systems Case Study: Ultra-Low Harmonic Drives Protect Transformers and Power Grid

Posted By John Wilmes, Saturday, September 01, 2007
Updated: Saturday, February 09, 2013

According to the United States Geological Survey, the average American uses about 100 gallons of water each day. This, in turn, creates more than 31 billion gallons of wastewater, which is cleaned and recycled by wastewater treatment plants across the country. Under the Homeland Security Act, wastewater facilities play a critical role in the needs of communities; ensuring wastewater is properly treated, especially in emergency situations.

With 450 miles of sanitary sewer-collection lines and 33 lift stations that feed into a central wastewater treatment plant, the city of Lawrence, Kansas, wastewater management system is extensive. The city has been recognized as one of only two in the nation that have three environmental management certifications for wastewater operations. These certifications demonstrate the city’s ability to provide customers with an efficient level of service, while maintaining a high standard of environmental protection.

Photo 1. Ultra-low harmonic drives feature bypass valve, fuse disconnect, remote I-O and selector switches.

Increasing Demand Brings Need for Retrofit

Gravity is the driving force for wastewater distribution to the treatment plant, except where there are vertical elevation changes in the topography. In these circumstances, lift stations—structures that contain pumps and controls—are used to move wastewater to the treatment plant.

Because of ongoing increases in demand, Dave King, wastewater maintenance manager, city of Lawrence, is continually looking for ways to improve efficiency. He explains that lift station number 16, built in 1958 and located close to downtown Lawrence, is responsible for transporting approximately 600 million gallons of dry weather-flow a year, about 25–30 percent of the city’s wastewater usage. The combination of aging equipment and increasing flow from new residential developments led to the decision to retrofit the station completely in the spring of 2006. King turned to the city’s long-time PLC supplier, Logic, Inc. to help develop a solution.


Photo 2. Test instruments (CTs and metering equipment) being connected after the equipment is deenergized and placed in an electrically safe work condition conforming to NFPA 70E.

Logic recommended installing ACS800 drives on each of four new 125-hp pump motors to increase efficiency and power factor to improve electricity cost savings; to extend the life of the motors and reduce repair costs; and to minimize or eliminate an addition of harmonics that can interfere with instrumentation and overheat feeder breakers and transformers.

Drives Ensure Constant Flow


Photo 3. ABB ACS800 drives power pump at lift station. One remains on standby.

When wastewater enters a lift station, it initially goes through a coarse screening process, which removes solid particles that might cause damage to the pumps. The wastewater then flows into an enclosed wet well, which can be 30–40 feet deep. Sensors monitor the depth of the wastewater in the wet well. Pumps are used to displace the wastewater from the well to the treatment facility. Drives often play a key role in supporting the pump operation, ensuring that a constant flow is discharged to maintain optimum wastewater levels.

"By controlling pump speed, an optimum level can be maintained that ensures constant flow between what’s coming in and what needs to be pumped out,” says King. "Installing the ABB drives has enabled us to eliminate unnecessary pump starts.”

From Across-the-Line Starter and Constant Speed to Variable-Speed Control
Previously, the site ran the pumps based on an on/off level, and used an across-the-line starter. When the level in the wet well reached a designated point, it would trigger the starter to get the pump motors up to maximum speed as quickly as possible. This rapid acceleration created spikes and mechanical stress on both the motor and pump. It would run at full speed until it reached the "off” level elevation—and then it would turn off. The constant-speed, starting-and-stopping process caused wear and tear on the bearings and impellers, causing the motors to deteriorate.

Prevent Water Hammers


Photo 4. Close-up of operation panel of power pump

By maintaining a consistent level in the lift station wet well, drives also help to avoid water hammers. When a pump starts or stops suddenly, it slams the check value on the back of the pump and creates a water hammer effect. Water hammers are pressure surges caused by the energy of a fluid in motion when it is forced to stop suddenly. In plumbing, this is experienced as a loud banging noise that sounds like a hammer hitting the pipes. The shock wave causes pipes to rattle and shake violently.

In a lift station, hydraulic water hammers often occur when trying to pump fluid vertically or at a slant. Once a pump stops, the fluid will come back to the source, jarring the piping. Over time, water hammers can lead to pipe deterioration. Because the ACS800 drives provide acceleration and de-acceleration ramp to the pumps, wear and tear on the pump mechanicals are reduced.

Keep Drive at the Ready; Balance Usage on Others


Photo 5. Interior of the pumping station

Drives also incorporate a soft-start function that gently ramps speed to limit potential turbulence—and reduce the need for maintenance. The drives respond to sensors in the wet well that are relayed to a PLC unit via DeviceNet. The wastewater treatment plant communicates with the PLC unit at the lift station via Ethernet to ensure that wastewater levels are being pumped out consistently, based on established parameters. Although three pumps are needed to run the station, the city keeps an installed fourth pump on stand-by at all times, running them alternately to balance wear on them. The station operates 24-hours a day and cannot afford downtime.

"ABB drives give us the ability to handle the wide range of variations in wastewater flow entering the station due to time of day, time of year and weather conditions, as well as the capacity to accommodate future growth,” says King. "The fact that we can now pump wastewater out at the same rate it enters also helps us reduce odors.”

By-Pass Feature Important for Constant Uptime

Since wastewater is constantly running throughout the city, another important feature to the lift station is the by-pass function, which allows a manual override of the pump if a drive were to go offline.

"Even though modern drives are very reliable, if for any reason we were to have multiple drive failures, the bypass gives us the ability to still operate the station,” explains King. "At this location, station down-time is not an option.”

Ultra-Low Harmonic Drives Provide Protection to Power Grids

Because the lift station is located next to a residential district, minimizing harmonic distortion is a necessity. With the amount of dynamic load on the existing transformer, standard drives were not a viable option. "Excessive harmonics can interfere with pump instrumentation,” King says. "Plus, we didn’t want to cause any interruption to the electrical appliances of our customers.”

Ultra-low harmonic drives do not require a multi-pulse transformer, external filters or other additional equipment for minimizing harmonics. The drive features an active converter with direct torque control (DTC) to eliminate low-order harmonics. With an active front-end LCL (Inductor, Capacitor, Inductor) line filter to reduce high frequency harmonics, the city did not have to worry about overheating feeder breakers or transformers.

Drives Offer Turnkey Solutions – Easy Installation

King was impressed with ABB because of its ability to offer turnkey solutions direct from the factory. "We required certain features in the cabinet, such as a by-pass, fuse disconnect, remote I/O and selector switches. ABB was able to provide all that from a factory service center,” he says. Since the lift station fits in a 900-square-foot space, the ACS800’s compact footprint fit well into the facility.

Since the drives were shipped with all of the specifications pre-installed, installation was a smooth and easy process. To maintain constant uptime during the retrofit, two pumps were taken off-line at a time, keeping the other two pumps running.

Results Foster Continued Relationship

The lift station retrofit was not the first instance where the city has benefited from using these drives. The wastewater treatment facility also has ABB drives equipped with bypass to increase efficiency. Because of the positive experience with the drives at lift station number 16, the city is installing drives in four other wastewater pump stations now under construction.

King concludes, "I really appreciate the technical assistance and customer service we have received. I anticipate extended pump life, electric cost savings, and ultimately better service to our customers as a result of the drives.”


Read more by John Wilmes

Tags:  Featured  September-October 2007 

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Inspecting to the 2008 National Electrical Code

Posted By Alan Manche, Saturday, September 01, 2007
Updated: Saturday, February 09, 2013

Just like clockwork, the 2008 edition of theNational Electrical Codeis now available, which always brings a plethora of education and materials on the changes taking place in the NEC. Understanding the changes is important to electrical inspectors in order to understand the safety or enforceability enhancements that have been made to support an electrical installation.

Let’s take a brief look into the future and explore a few of the new items one will find when inspecting to the 2008NEC.

Residential

Let’s peer into a home that has been wired in accordance with the 2008 NEC. One of the first recognizable differences will be the tamper-resistant receptacles located throughout the home. NEC 406.11 requires that all 125-V, 15- and 20-A receptacles of the home installed in accordance with NEC 210.52 be tamper-resistant. These new receptacles will provide needed protection from children inserting narrow metal objects into a single slot of the receptacle, which can create a shock or burn hazard.

Before progressing through the rest of the home, it is a good idea to proceed directly to the garage, basement or other service location to locate the load center, in order to understand if the electrical contractor has been wiring to the 2008 NEC. Upon arriving at the load center, one will notice a number of differences—a much longer panel that has more than 50 circuits installed; more AFCI circuit breakers than before with different-colored test buttons; an automatic transfer switch as part of the service panel, along with a controller that appears to automatically control loads; and finally, surge protection with a Type 2 designation. At this point, an electrical inspector might be thinking, "Is this a fancy house with all the bells and whistles or did I miss a few things during all those code education classes?”

The panel with 54 circuits is obviously the answer by the electrical equipment manufacturers to support customers with more circuits in a panel and is based on the elimination of the 42-circuit limitation in Article 408. One caution in looking at this type of installation is that the panel still has to be listed for the number of circuits installed. Read the label to make sure that the installer did not take a normal 42-circuit panel and make some tandem or ½ breakers "fit” into the existing space. The panel labeling will indicate how many circuits can be legitimately installed. Do not forget to check the listing of the cable clamps used to attach the NM cables to the enclosure; it may be that with all those additional circuits, the contractor has doubled up and even tripled up on NM cables in the cable clamps. There is a good possibility a violation exists where more than two cables are in a clamp. However, if the clamp is evaluated for more than two cables, the tripled up versions may be acceptable.

It appears the number of AFCIs have doubled in this panel as compared to a similar size home. NEC 210.12 has expanded the requirement for combination AFCIs to protect additional circuits in most of the rooms that are found in NEC 210.52(A)—those rooms that are required to have receptacle spacing around the room, along with closets and hallways. The change in test button color also is explained by the change from the branch feeder AFCI to combination AFCI. You may recall the combination AFCI requirements will go into effect January 1, 2008, based on an effective date that was in NEC-2005. The test button color is one method that manufacturers are using to support easier inspection.

The integrated automatic transfer equipment in this panelboard could raise some questions. These innovations are once again driven by a 2008 NEC change based on concerns expressed by the electrical inspection community. NEC 702.5 requires adequate capacity from the alternate source of power. The issue resides when an automatic transfer places a load on the source that it cannot support. NEC 702.5(2) has been added in order to require the generator to carry the entire load or it requires that a load management means be put in place to limit the load. The controller within this panel is likely serving the load management function to support the revised language in NEC 702.5.

There is no "TVSS” or "Surge Arrester” marking on a Type 2 surge protection device. Similar to the popular move from the terminology fixture to luminaire, the surge protection industry has revised the terms in NEC Article 285 from TVSS to SPD or surge protection device. The type rating establishes where it can be installed. Type 2 is permitted on the load side of the service disconnect, similar to TVSS. A Type 1 device would be permitted on the line side of the service disconnect similar to secondary surge arresters. Finally, a Type 3 device must have 30 feet of conductor between it and the service panel. The bottom line is that a Type 2 SPD is acceptable in this installation because it is installed on the load side of the service disconnect at the service panel.

The more an inspector looks around a home the more changes he will likely recognize. For instance, there may be no dedicated receptacle outlets for appliances in the garage or basement. These additional GFCI-protected receptacles are a result of the exceptions being removed from the NEC 210.8(A). Since the exceptions were about 20 years old, it looks like the code panel has finally eliminated them and caught this section up with the modern UL listed appliance requirements that have leakage limitation. That certainly makes the installation easier to inspect.

Moving outside, an inspector is reminded that receptacles in a damp or wet location are required to be listed as weather-resistant in accordance with NEC 406.8. If a house also has a deck on the back, an inspector will want to verify the contractor understood the new requirement in 210.52(E)(3) that there be a receptacle installed within the perimeter of the deck. This receptacle cannot be used to meet the requirements for a receptacle installed in the back of the house unless it is accessible while standing at grade level. The inspector may find a pool around back, the requirements that surround grounding, bonding and the equipotential plane are far too much to discuss in this venue. The one revision that is worth noting is that hard-wired pool pump motors are now required to be GFCI-protected in accordance withNEC680.22(B).

Commercial/industrial

There are also a number of changes in the 2008NECthat impact electrical installation in commercial and industrial buildings. For example, entering the rear of a mall, one may see a 4,000 A electrical service, with panic hardware installed on a couple of doors that are the entrances to the area where the equipment is installed, but not doors that are in the working space. NEC 110.26(C)(3) has introduced the requirement for panic hardware on doors within 25 feet of the working space.

Just across the hall is a door that leads to a janitorial closet with a sink. The sink has a disposal installed that is plugged into a receptacle under the sink.NEC210.8(B)(5) now requires GFCI protection of 125-V, 15- and 20-A receptacles within 6 feet of sink. The requirement related to outdoor receptacles in other than dwelling locations was also expanded. GFCI protection is now required for all outdoor 125-V, 15- and 20-A receptacles regardless of whether they are accessible by the public, so an inspector might find a few receptacles for holiday decorations or receptacles behind fences that have been missed by the installer regarding this requirement.

The conduit running across the roof may remind an inspector of the ampacity derating that is now required in NEC 310.15(B)(2)(c) for conduits exposed to sunlight. The derating is based on the distance of the conduit from the roof. An inspector must check conductor sizes in the air unit and understand the load placed on them to inspect for the correct wire size after derating.

In looking at the lighting panelboards, an inspector might notice that the designer utilized a number of multiwire branch circuits, using a common neutral conductor for two or sometimes three lighting circuits. NEC 210.4(B) now requires that all multiwire branch circuits have a common disconnect that will open all the ungrounded conductors of the circuit. This will mean that either two- or three-pole circuit breakers will be needed or handle ties could be used with two single-pole breakers. Also NEC 210.4(D) now requires that the multiwire branch-circuit conductors (grounded and ungrounded) be grouped in at least one location within the panelboard. This allows for easy identification of which grounded conductor goes with which ungrounded conductors. There is no wire tie or grouping means found in these panels.

Final thoughts

The 2008 NEC introduces a significant number of changes that enhance safety for property and people in both residential and commercial/industrial environments. Electrical safety is an expectation of the citizens of this country and the 2008 NEC delivers on that expectation of enhancing safety through technology and enhancements based on a better understanding from industry representatives that bring knowledge and experiences of potential hazards from electrical installations. Electrical inspectors play a key roll in developing the NEC, driving uniform enforcement and ensuring the safety of every community.


About Alan Manche: Alan Manche is the director, industry standards for Square D/Schneider Electric. He is a licensed professional engineer in the state of Kentucky. He is a former member of NEC Code-Making Panel 8 and served as a member of NEC Code-Making Panels 10 and 20 during the development of the 2008 NEC. He also serves on the technical committee for NFPA 70B - Electrical Equipment Maintenance, NFPA 110 - Emergency and Standby Power Systems, and numerous UL product standard STPs. He has served as a product design engineer with responsibility for product certification of numerous Square D product lines including panelboards, switches, and busway. Alan also serves as a Schneider Electric liaison to the electrical inspection community, providing NEC educational programs across the country for inspectors and contractors.

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Inspecting to the 2008 National Electrical Code

Posted By Alan Manche, Saturday, September 01, 2007
Updated: Saturday, February 09, 2013

Just like clockwork, the 2008 edition of the National Electrical Code is now available, which always brings a plethora of education and materials on the changes taking place in the NEC. Understanding the changes is important to electrical inspectors in order to understand the safety or enforceability enhancements that have been made to support an electrical installation.

Let’s take a brief look into the future and explore a few of the new items one will find when inspecting to the 2008NEC.

Residential

Let’s peer into a home that has been wired in accordance with the 2008 NEC. One of the first recognizable differences will be the tamper-resistant receptacles located throughout the home. NEC 406.11 requires that all 125-V, 15- and 20-A receptacles of the home installed in accordance with NEC 210.52 be tamper-resistant. These new receptacles will provide needed protection from children inserting narrow metal objects into a single slot of the receptacle, which can create a shock or burn hazard.

Before progressing through the rest of the home, it is a good idea to proceed directly to the garage, basement or other service location to locate the load center, in order to understand if the electrical contractor has been wiring to the 2008 NEC. Upon arriving at the load center, one will notice a number of differences—a much longer panel that has more than 50 circuits installed; more AFCI circuit breakers than before with different-colored test buttons; an automatic transfer switch as part of the service panel, along with a controller that appears to automatically control loads; and finally, surge protection with a Type 2 designation. At this point, an electrical inspector might be thinking, "Is this a fancy house with all the bells and whistles or did I miss a few things during all those code education classes?”

The panel with 54 circuits is obviously the answer by the electrical equipment manufacturers to support customers with more circuits in a panel and is based on the elimination of the 42-circuit limitation in Article 408. One caution in looking at this type of installation is that the panel still has to be listed for the number of circuits installed. Read the label to make sure that the installer did not take a normal 42-circuit panel and make some tandem or ½ breakers "fit” into the existing space. The panel labeling will indicate how many circuits can be legitimately installed. Do not forget to check the listing of the cable clamps used to attach the NM cables to the enclosure; it may be that with all those additional circuits, the contractor has doubled up and even tripled up on NM cables in the cable clamps. There is a good possibility a violation exists where more than two cables are in a clamp. However, if the clamp is evaluated for more than two cables, the tripled up versions may be acceptable.

It appears the number of AFCIs have doubled in this panel as compared to a similar size home. NEC 210.12 has expanded the requirement for combination AFCIs to protect additional circuits in most of the rooms that are found in NEC 210.52(A)—those rooms that are required to have receptacle spacing around the room, along with closets and hallways. The change in test button color also is explained by the change from the branch feeder AFCI to combination AFCI. You may recall the combination AFCI requirements will go into effect January 1, 2008, based on an effective date that was in NEC-2005. The test button color is one method that manufacturers are using to support easier inspection.

The integrated automatic transfer equipment in this panelboard could raise some questions. These innovations are once again driven by a 2008 NEC change based on concerns expressed by the electrical inspection community. NEC 702.5 requires adequate capacity from the alternate source of power. The issue resides when an automatic transfer places a load on the source that it cannot support. NEC 702.5(2) has been added in order to require the generator to carry the entire load or it requires that a load management means be put in place to limit the load. The controller within this panel is likely serving the load management function to support the revised language in NEC 702.5.

There is no "TVSS” or "Surge Arrester” marking on a Type 2 surge protection device. Similar to the popular move from the terminology fixture to luminaire, the surge protection industry has revised the terms in NEC Article 285 from TVSS to SPD or surge protection device. The type rating establishes where it can be installed. Type 2 is permitted on the load side of the service disconnect, similar to TVSS. A Type 1 device would be permitted on the line side of the service disconnect similar to secondary surge arresters. Finally, a Type 3 device must have 30 feet of conductor between it and the service panel. The bottom line is that a Type 2 SPD is acceptable in this installation because it is installed on the load side of the service disconnect at the service panel.

The more an inspector looks around a home the more changes he will likely recognize. For instance, there may be no dedicated receptacle outlets for appliances in the garage or basement. These additional GFCI-protected receptacles are a result of the exceptions being removed from the NEC 210.8(A). Since the exceptions were about 20 years old, it looks like the code panel has finally eliminated them and caught this section up with the modern UL listed appliance requirements that have leakage limitation. That certainly makes the installation easier to inspect.

Moving outside, an inspector is reminded that receptacles in a damp or wet location are required to be listed as weather-resistant in accordance with NEC 406.8. If a house also has a deck on the back, an inspector will want to verify the contractor understood the new requirement in 210.52(E)(3) that there be a receptacle installed within the perimeter of the deck. This receptacle cannot be used to meet the requirements for a receptacle installed in the back of the house unless it is accessible while standing at grade level. The inspector may find a pool around back, the requirements that surround grounding, bonding and the equipotential plane are far too much to discuss in this venue. The one revision that is worth noting is that hard-wired pool pump motors are now required to be GFCI-protected in accordance withNEC680.22(B).

Commercial/industrial

There are also a number of changes in the 2008NECthat impact electrical installation in commercial and industrial buildings. For example, entering the rear of a mall, one may see a 4,000 A electrical service, with panic hardware installed on a couple of doors that are the entrances to the area where the equipment is installed, but not doors that are in the working space. NEC 110.26(C)(3) has introduced the requirement for panic hardware on doors within 25 feet of the working space.

Just across the hall is a door that leads to a janitorial closet with a sink. The sink has a disposal installed that is plugged into a receptacle under the sink.NEC210.8(B)(5) now requires GFCI protection of 125-V, 15- and 20-A receptacles within 6 feet of sink. The requirement related to outdoor receptacles in other than dwelling locations was also expanded. GFCI protection is now required for all outdoor 125-V, 15- and 20-A receptacles regardless of whether they are accessible by the public, so an inspector might find a few receptacles for holiday decorations or receptacles behind fences that have been missed by the installer regarding this requirement.

The conduit running across the roof may remind an inspector of the ampacity derating that is now required in NEC 310.15(B)(2)(c) for conduits exposed to sunlight. The derating is based on the distance of the conduit from the roof. An inspector must check conductor sizes in the air unit and understand the load placed on them to inspect for the correct wire size after derating.

In looking at the lighting panelboards, an inspector might notice that the designer utilized a number of multiwire branch circuits, using a common neutral conductor for two or sometimes three lighting circuits. NEC 210.4(B) now requires that all multiwire branch circuits have a common disconnect that will open all the ungrounded conductors of the circuit. This will mean that either two- or three-pole circuit breakers will be needed or handle ties could be used with two single-pole breakers. Also NEC 210.4(D) now requires that the multiwire branch-circuit conductors (grounded and ungrounded) be grouped in at least one location within the panelboard. This allows for easy identification of which grounded conductor goes with which ungrounded conductors. There is no wire tie or grouping means found in these panels.

Final thoughts

The 2008 NEC introduces a significant number of changes that enhance safety for property and people in both residential and commercial/industrial environments. Electrical safety is an expectation of the citizens of this country and the 2008 NEC delivers on that expectation of enhancing safety through technology and enhancements based on a better understanding from industry representatives that bring knowledge and experiences of potential hazards from electrical installations. Electrical inspectors play a key roll in developing the NEC, driving uniform enforcement and ensuring the safety of every community.


Read more by Alan Manche

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Battery Rooms – Accidents Waiting to Happen?

Posted By Michael Weitzel, Saturday, September 01, 2007
Updated: Saturday, February 09, 2013

Dangerous conditions exist in battery rooms all over the country, but the batteries themselves are not a hazard. The hazards come from working conditions that are often unsafe because of limited paths of egress or escape, poor lighting, no working clearances, no guards for exposed live parts, and little or no ventilation. It is often difficult for the electrical worker to de-energize the battery system for maintenance, repair, or replacement of equipment. Even when disconnected from the rest of the bank, individual batteries remain energized; however, when connected to the bank, voltages may be high, and amperages even higher, which means considerable stored electrical power is present. Grounded concrete or cement surfaces often surround the battery bank, increasing the danger of the workspace. Is the worker even aware of the safety risk?

This article will discuss how these potentially serious safety concerns can be lessened.

Photo 1

Batteries are used for emergency, legally required, optional power, fire alarm, security, telecommunications, smoke alarms, and photovoltaic systems, along with many other electrical uses. For instance, Section 700.12(A) permits storage batteries to be a source of emergency power if they have suitable capacity and can carry the load for a minimum of 1.5 hours, and can maintain the voltage of the system at acceptable levels. Section 700.4 covers emergency power systems testing, and requires witness testing, periodic testing, testing under load, and maintenance. Written maintenance records are to be kept on file. If storage batteries are utilized as part of an emergency power system, these requirements apply.

Scope

The scope ofNEC480 "applies to all stationary installations of storage batteries,” which is significant, and many electrical professionals may not realize this fact. The wiring and equipment supplied by storage batteries is subject to the same applicable provisions of this Code as other equipment that operates at the same voltage (480.3). The working clearance requirements in Section 110.26 apply, for example, but so do the requirements found in Sections 110.11, 110.12, 110.13, 110.14, 110.16, 110.18, 110.22, 110.26, and 110.27, just to name a few.

Overcurrent Protection


Photo 2. Battery bank with disconnect and overcurrent protection

Storage batteries—with the exception of those that are rated at 50 volts that are used for starting, igniting, or controlling prime movers, such as electrical generators, for example—require overcurrent protection. The point here is that most storage battery installations require overcurrent protection. The question is, does a fuse or circuit breaker protect the battery conductors from overcurrent in the installations that you work on? Frequently, when you investigate you may find there is no overcurrent protection present or provision for it in the installation, even though the Code began requiring overcurrent protection in the 2002 edition. The requirements are there for good reason. Current can be very high in storage battery systems, and may introduce serious hazards to those that work on or around the equipment. Care and thought must be always be exercised before working on or around any storage battery system.

Disconnecting Means

In NEC-2008, new requirements have been added for disconnecting means of all ungrounded conductors derived from a stationary battery system that is rated at over 30 volts (see ROC 13-21). The disconnecting means is required to be readily accessible, and to be located within sight of the battery system. Within sight as defined in Article 100 is "visible and not more than 15 m (50 ft) distant from.” This new requirement came as the result of the need for qualified persons to disconnect safely electrical power to battery systems for maintenance. Having a localized disconnecting means helps maintenance to be performed in a safer manner.

The disconnecting means is not required to have a locking means that remains in place as part of the equipment, though it would be helpful to safety. OSHA rules require lock-out and tag-out procedures, which are in addition to but not included in the NEC.

Storage batteries in operation may be supplying power to loads or recharging. In other words, they may be supplying power to a load or receiving power via a battery charging system of some sort; or they may be connected to an uninterruptible power supply system, for example. At least two safety concerns must be considered here if work on the system is required while the system is being energized: (1) the disconnection or removal/replacement of batteries using wrenches or other hand tools, and (2) the presence of hydrogen or other gases. Therefore, qualified persons must follow safe work practices, wear proper personal protective equipment (PPE), make use of all protective guards and rubber insulating mats available, and utilize tools that have the appropriate voltage insulation rating.

Terminations


Photo 3. Damaged wiring terminations, improper lugs used for fine stranded conductors.

NEC 110.14(A) requires a "thoroughly good connection without damaging the conductors.” The fine stranded conductors used and associated with storage battery systems require termination in a properly sized and rated lug. Standard off-the-shelf mechanical lugs intended for use with solid or the larger stranded conductors for building wire in electrical installations may cause loose connection problems to develop when they are used with fine stranded conductors.

Racks and Trays

Racks for storage batteries are required to be rigid and substantial and made of either (1) metal and that is covered with a corrosion-resistant material, or (2) nonconductive materials such as fiberglass. Trays are frames, such as crates or shallow boxes made of wood or other nonconductive materials, which are constructed or treated to resist deteriorating action by the electrolyte; trays are required (see 480.8).

Battery Locations

Battery spaces generally require ventilation and diffusion of gases to prevent an explosive mixture from accumulating. Live parts generally must be guarded from contact by persons; for instance, by a partition or partitions that are permanent, so that only qualified persons have access to the live parts. Any openings in the partitions must be sized and placed in a manner to protect persons and conductive objects from coming in contact with them.

Installations must comply with chapters 1 through 4 of the Code. Article 480 does not stand out as a "lone ranger.” Section 110.3(B) requires installers and maintenance personnel to comply with the requirements and directions included within the battery manufacturer’s instructions. NEC 110.12 requires that systems be installed in a workmanlike manner. Is this happening in the storage battery installations that you see, maintain, or inspect?

Are the Batteries the Sealed or Vented Type?


Photo 4. Damaged wiring terminations, improper lugs used for fine stranded conductors.

Each vented cell battery is required to have a flame arrester to prevent destruction of the cell due to an external spark or flame igniting gases that may be discharged from the cell under normal operating conditions. Sealed cell batteries are required to have a pressure-relief vent to prevent excess gas pressure from accumulating, or the cells must be designed to prevent cell parts from scattering in case of an explosion.

All manufacturers’ requirements must be read and followed by the end user of the product. For example, one UPS manufacturer had supplied on-line type UPS units for the 911-dispatch center of a small town of 26,000 population. The battery manufacturer stated in its literature that the sealed batteries would last 3–5 years. Exactly three years later, a majority of the batteries failed. What happened was that one cell in one battery would fail, the battery voltage would rise to 56-vdc across that cell, the voltage on the 48-volt dc system would rise, and the sealed battery would vent unpleasant gases into the building. The room was ventilated, but not nearly enough to address this unforeseen circumstance. Thereafter, the batteries were replaced just prior to the three-year deadline, and the room ventilation was increased.

Hydrogen gas can be explosive in heavy concentrations. Most storage battery locations would not be considered as classified, which would require compliance with Article 501. In most cases, installation of required ventilation in accordance with Section 480.9 would be sufficient. Classification of areas depends upon a number of factors — in this case, the quantity and type of batteries installed, the amount of hydrogen gas given off by the batteries, the size of the area or room, the design engineering, the manufacturer’s instructions, and the work or other activities taking place in the area.

Common Code Violations with Battery Systems

The primary goal of this article is to raise awareness of electrical safety in battery installations. The general requirements found in chapters 1 through 4 of the Code apply to storage battery installations. As one very important example stated earlier, many electrical professionals have not yet realized that the minimum safe working clearance requirements in 110.26 apply to all storage battery installations under jurisdiction of the NEC. Crowded battery rooms where the worker does not have safe working clearance to install, to add, to repair, or to maintain the equipment are common; and these situations may present a serious hazard to the worker. Exposed live parts and concrete or brick/cement block wall and/or floor surfaces are considered grounded surfaces that increase the possibility of electric shock [see 110.27, 480.9(B), and 110.26(A)(1) Condition 2 under Table 110.26]. Electrical workers must always be aware that even with the disconnecting means (switch) in the open position, an individual battery or group of batteries remain energized and can be hazardous to the work because of the stored electrical energy. Existing lighting and ventilation may be inadequate for installation or maintenance of the battery system without creating a hazard. Good illumination and ventilation are essential for safety [see 480.9(A) and (B)].

Installations are not planned to be unsafe. Yet unsafe conditions in battery installations exist for a number of reasons. Although the installation may have met minimum Code standards under an earlier edition, (1) the installation may have been added on to; or (2) the original designer may have meant well, but have been unaware of safety requirements; or (3) some emergency event, natural disaster, severe power outage, or other unforeseen event may have necessitated temporary measures for backup power from storage batteries; or (4) there were exposed live parts; or (5) these temporary measures were never intended to stay, or at least were never intended to end up this way. There may also be other reasons yet unmentioned. Let’s face it, unsafe situations are often inherited from previous owners, installers, or management groups, and left for others to deal with. Regardless of how the situation occurred, with a little effort and initiative, worker and building safety can be improved.

Making Corrections/Improvements

What can be done to improve an unsafe condition in an existing storage battery installation? When considering making corrections to existing installations, you should evaluate each installation individually on its own merit. When the installation occurred and under which edition of the electrical code it was made should be determined. Input from the local AHJ could prove to be helpful in determining which corrections, if any, will be required. Hopefully, the AHJ is reasonable and will assist you by answering your questions and by dealing with existing conditions that are less than code-perfect.

The optimum may be a completely new battery room or a remodeled location. If a new battery room is an option, great! Often, however, one must do the best that one can to improve an existing installation and to make it safer. Ungrounded surfaces, such as plywood or gypsum wallboard, attached over existing concrete or otherwise grounded walls, for example, can remove the grounded surface from a Condition 2 workspace and improve worker safety (see Table 110.26). (Fire resistance ratings of building surfaces must also be considered when taking this approach, but if done right, there is an immediate possibility of improved worker safety). Where Table 110.26 Condition 3 workspaces exist, they could possibly be improved by installing insulated material or by better guarding of live parts.

Installing better illumination that is rated for the environment and providing or improving ventilation will help. Some workplaces have experienced lost time and worker complaints of breathing air contaminated by the venting of "sealed” batteries when unexpected problems arose or when maintenance guidelines were not followed.

Improving the rack or tray system, guarding live parts, installing overcurrent protection and a disconnecting means within sight of the installation all would improve worker safety. Identifying voltages, systems, and disconnecting means to disconnect the power, as well as identifying all storage battery systems if more than one exists in the same location, could also improve safety.

There may be other Code requirements such as those in mechanical and structural codes that are also applicable to this type of installation. In many cases, the NEC is not the only set of rules that would be applicable.

In this article, we have briefly discussed storage battery installations per NEC-2008, overcurrent protection, disconnecting means, terminations, racks and trays, battery locations, sealed or vented type batteries, common Code violations, and making corrections/improvements. The hope is that awareness of Code requirements and the possible hazards present in these types of installations has been raised, with the goal of seeing new installations installed in a manner that will promote worker safety, while providing some direction toward improving existing installations.


Read more by Michael Weitzel

Tags:  Featured  September-October 2007 

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Case Study: ITE and Cancer Treatment: Cutting Edge Technology Working Together

Posted By Tim McClintock, Saturday, September 01, 2007
Updated: Saturday, February 09, 2013

Cancer is one of the leading causes of death in the United States. It is expected that about 1.4 million new cases of cancer will be diagnosed in 2007, according to the American Cancer Society’s Cancer Facts and Figures 2007.1 Due to advances in medical technology, however, trends in five-year relative survival have improved greatly from 50 percent in 1975 to 66 percent in 2002, according to the study.


Photo 1. Mark H. Zangmeister Center

Mid Ohio Oncology/Hematology (MOOH) located at 3100 Plaza Properties Blvd., in Columbus, Ohio, is one of many treatment centers throughout the country that has been instrumental in the increase of the survival rate. MOOH, which was established in 1982, offers care and treatment for disease management of cancer and blood disorders in and around Central Ohio. Currently, MOOH operates four outpatient treatment centers in Columbus and its suburbs.

Mark H. Zangmeister Center


Photo 2. Linear accelerator which produces 23 million electron volts uses radiation to shrink tumors

In an effort to consolidate the outpatient treatment centers and provide a more patient friendly environment, MOOH completed construction of a new 109,000 square-foot, privately funded, outpatient cancer treatment center in May 2007. The facility, named the Mark H. Zangmeister Center2 after one of Central Ohio’s most respected oncology physicians, will be able to accommodate 16,000 patients in one year and over 60,000 patient visits per year. The center will offer 90 infusion chairs, which cancer patients use for chemotherapy treatment; 53 exam rooms; and a diagnostic imaging and radiological unit. Additionally, two linear accelerators, which produce 23 million electron volts each, use radiation to shrink tumors. "Radiation treatment employed today is more precise than in years past, the linear accelerators utilized by the Mark H. Zangmeister Center have on-board imaging, which ensures precision within millimeters when treating a cancer patient,” said Glenn Balasky, executive director for the center.


Photo 3. An emergency power off (EPO) button complying with the disconnecting requirements of 645.10 located at the principal exit door

"Treatment of cancer patients over the last 20 years has evolved from being an in-patient care procedure to an outpatient care procedure, as a result of the advancement in medical technology,” Balasky said. Often, cancer can be successfully treated with chemotherapy, radiation and sometimes medication, as opposed to surgery, according to Balasky.

Information in Electronic Format

In today’s world, the use of computers and electronic devices has become widespread and the Mark H. Zangmeister Center is no exception. Electronic medical records have become the backbone of top-quality patient care. The complexity of treating a cancer patient means keeping multifaceted information on file. Rendering this information in electronic format makes it possible for doctors to have complete patient information right at their fingertips, whether it is accessing lab results, fielding a call on the weekend and being able to review needed information via the internet, or making a referral.

"During the design stages of the center, emphasis was placed on the migration from a partially integrated networking system to a fully integrated networking system as well as security, with the ability to expand and yet to preserve the integrity of this system,” said information technology (IT) manager Andrew Cooper. "Today’s technology is temporary in that today’s technology is obsolete tomorrow,” according to Cooper.

Design Challenges and Versatility Faced


Photo 4. Dedicated underfloor cooling unit is utilized to control ambient conditions

The center was faced with challenges early on, such as being unsure how to proceed with construction of the data center room, and knowing that the integrity of the computer network was essential to the overall operation of the center. Additionally, because versatility is essential to rapidly developing medical technology, considerations had to include the ability to replace equipment without an expensive retrofit.

During the initial stages of construction, the design and layout of the data center room had not been finalized. Included in the design, however, were self-contained HVAC systems and a raised floor system. Ralph Butcher, city of Columbus electrical inspector, suggested the center explore the option of utilizing NEC 645 as a design option, which would address the concern of providing a secure environment for the IT equipment, along with ease of equipment replacement.

Compliance with NEC 645

It is important to recognize that Article 645 is optional. Article 645 relaxes some of the code requirements, permitting normally prescriptive installation methods and materials to become less strict. Consequently, it is important to note that in order to qualify under Article 645; the five conditions set forth in 645.4 must be met:

  • Disconnecting means complying with 645.10 are provided.
  • An HVAC system is provided that is dedicated for information technology equipment use, or a common HVAC system with fire/smoke dampers is installed.
  • Only listed IT equipment is installed.
  • The only occupants that may be admitted are personnel necessary for the maintenance and functional operation of the IT equipment.
  • The room is separated from other occupancies by fire-resistant-rated walls, floors, and ceilings with protected openings.

Photo 5. 80 kW uninterrupted power supply (UPS) ensures continuity of mission critical systems

Chapters 1 through 4 of the NEC are mandatory, and chapters 5, 6 and 7 apply to special occupancies, special equipment or other special conditions. These chapters describe applications when certain additional requirements are necessary or when certain exceptions can be made to provisions found in the previous four chapters. If the allowances granted by Article 645 are not needed, installation in accordance with chapters 1 through 4 is all that is required.

The initial design of the IT equipment room already included a unlimited power supply system, two separate HVAC systems, a Liebert underfloor cooling system and in-rack cooling system; the equipment to be installed was listed IT equipment; and access to the room was limited to IT personnel. An additional safeguard included in the design was a 200-kVA optional standby generator system that is independent of the building’s emergency generator system.


Photo 6. Listed ITE rack storage system

By its inherent design and by recognizing that the leniencies prescribed by Article 645 would be beneficial, the designers made the logical design choice to proceed with Article 645. Subsequently, the center consulted with American Power Conversion (APC) for design services and proceeded with an Article 645 installation. Meeting the requirements prescribed by Article 645, the Zangmeister Center has a reliable IT equipment installation that is designed to evolve with changing technology.

Conclusion

The Mark H. Zangmeister Center simplifies access to medical expertise by providing complete testing, treatment and support services for cancer patients, under one roof. "With 14 physicians on staff and advancements in medical technology, it is with great hope we can increase the five-year survival rate from 60 percent today, to maybe 70 or 80 percent tomorrow,” says Balasky.

1 American Cancer Society. Cancer Facts & Figures 2007. Atlanta: American Cancer Society: 2007

2 The Mark H. Zangmeister Center is located at 3100 Plaza Properties Blvd., Columbus, Ohio 43219


Read more by Tim McClintock

Tags:  Featured  September-October 2007 

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Electrical Inspection Is Indispensable for Electrical Safety

Posted By Michael Johnston, Saturday, September 01, 2007
Updated: Saturday, February 09, 2013

It is essential for safety that jurisdictions establish and maintain an effective code enforcement program. Inspections of installed work provide an opportunity to identify and correct potential hazards, such as shock, electrocution, fire and others, before some catastrophe occurs. Other benefits of code enforcement and building inspections are the positive affects on insurance rates and the reduced number of fires and injuries.

Numerous fires and injuries related to electrical installations or building construction generally indicate a deficiency in the code enforcement program. Unfortunately, people who do not fully understand the hazards of electrical safety often have difficulty comprehending the importance of the inspector’s responsibilities in electrical and building safety and in conformance assessment. For that reason, the importance of proactive electrical safety must be conveyed vigorously and visibly. This article examines electrical inspections and the indispensable role of the inspector. "The practical safeguarding of persons and property from hazards arising from the use of electricity,” as clearly indicated in Section 90.1, is the primary purpose of the National Electrical Code. This concept should always be kept in mind when applying and enforcing the rules contained in the Code. Electrical inspectors know and understand this; it is the driving force of their dedication and commitment to electrical safety.

Photo 1. Typical equipment labels containing applicable information on use

 


Photo 2. Good electrical conductor connections and terminations are critical (see NEC 110.14)

 

Minimum safety rules are basic

The Code contains the minimum set of safety rules and requirements that are essential for safety. That means one must do at least that much in the interest of electrical and building safety. When the minimum requirements of the Code are met, and proper maintenance is provided as needed, installations are essentially free from hazards; but they might not necessarily be adequate for future expansion of electrical use [see 90.1(B)].

Local jurisdictions commonly amend or modify the minimum international and national standards with local requirements, as deemed necessary. These amendments or modifications usually are more restrictive and are for specific conditions unique to that region or area. One example is local amendments that deal with harsh soil conditions and the negative effects the soil has on electrical equipment in contact with the earth. Another example would be amendments to compensate for the effects of more intense heat or the levels of ultra-violet rays in sunlight on electrical equipment. Various other reasons might necessitate local amendments to the Code. Jurisdictions adopting the NEC into law should exercise careful discretion and consideration before modifying the minimum electrical safety standards.

Electrical inspection checklists offer guidance

Checklists promote consistency and uniformity in the application of the rules and serve as effective training tools for the inspector and installer. Checklists are great starting points but they are generally non-inclusive; each job has a certain amount of uniqueness, which might require diversion from any basic checklist. The best approach is to use the checklists as guides and to treat each installation with individual attention, always remembering that the NEC is the umbrella for any checklist. This means, do not rely on the checklist(s) alone; rely on the Code.

Accurate workmanship is important


Table 1. Ten essential electrical inspections

If a job is worth doing, it is worth doing right. Therefore, all electrical equipment (see definition of equipment) is to be installed in a neat and workmanlike manner, in accordance with Section 110.12. Good electrical work usually looks good as well, and the comfort level of inspectors is generally raised by the quality and appearance of the work. While it is not hard for electrical inspectors to tell if the electrical installer has experience and meets the objectives anticipated in the workmanlike-manner rule, it is also important that the inspector not get too comfortable because the work looks good from outside appearances. An installation can appear neat and workmanlike on the surface but contain serious problems inside. This important consideration will affect the approach of the installer and the electrical inspector.

When applying the general requirements of the NEC, a few of the many essential inspections come to mind (see table 1).

Listing and installation instructions must be enforced

Of first importance is the approval process and how the inspector utilizes listing and the use of listed products as a basis for approvals; this process is a primary contributor to electrical safety. In this process, the inspector verifies that the equipment or material is listed. Listed equipment has been evaluated for electrical safety; generally, the manufacturer provides installation instructions on its use and the limits of its use. Not following the installation instructions is a common violation in the field, yet it is a reasonable Code rule that is easy to comply with and to enforce. It is amazing to witness how many folks still do not follow installation instructions. Section 110.3(B) is clear and offers no exceptions. There are three other critical areas in electrical installations to which the rules in chapter one of the Code apply. They are equipment interrupting ratings covered in Section 110.9; electrical terminations and connections covered in Section 110.14; and adequate working space and dedicated space for electrical equipment covered in 110.26.

Equipment ratings and use

Equipment must have sufficient electrical ratings for the voltage, current, phase and system, etc., and must be applied in systems while not exceeding those limits [see NEC 110.9]. Examine carefully the labels that are required to be on the equipment (see photo 1). There is a plethora of information to be understood from just the equipment labels. An enormous amount of information needs to be included on the labels and it seems to require smaller and smaller print to get it all on the labels. Magnifying glasses and angle mirrors are common tools for inspectors these days to assist with these challenges. Installers should have a good understanding of the markings on equipment as well. Manufacturers of electrical equipment are more than happy to provide additional guidance and information as needed, but one must request the information. It is tough to learn at the end of a red tag or an inspector’s notice of violation in the field.

Electrical terminations and connections

Electrical circuits are only as good as their weakest link. Common points for electrical failures are connections and terminations at equipment and devices such as switches and receptacles (see photo 2). Follow the weakest link theory when installing or inspecting electrical terminals and connections. Be sure that the terminal or connection device is suitable for the use and properly installed. This includes compatibility between conductor materials and the device, proper torque, and ratings, etc. Improper connections and terminations are primary causes of electrical failures and fires.

Working spaces for electrical equipment


Photo 3. Minimum working space is required for electrical equipment

The minimum working spaces required in chapter one for electrical equipment are necessary for ready and safe operation of such equipment (see photo 3). When installing electrical equipment that requires the minimum working and dedicated space, installers should approach the situation as though they might have to service the equipment or work on it in the future. Enough working space to meet the minimum distances provided in Article 110 of the Code is essential for safety, and is a definite electrical inspection must. See 110.26 and 110.32, 110.33, and 110.34 for the minimum distances required for equipment based on applied voltages.

Circuit and disconnecting means identification

Identification of circuits and disconnecting means as to the load served is an essential part of the inspection (see 110.22) and should be approached from the viewpoint of the occupant’s safety. The primary beneficiary of a carefully thought-out circuit directory on a switchboard, panelboard, motor control center, etc., is the occupant or user long after the final inspection and building occupancy is taken. Installers and inspectors sometimes get a bit too casual with circuit identification requirements. Changes in NEC-2008 have added emphasis and requirements to address this issue [see the revisions to Section 408.4].

Protection of persons, equipment, and property


Photo 4. GFCI protection provided to comply with 210.8(A)(1) at a wet bar sink

Chapter two, "Wiring and Protection,” contains hundreds of minimum requirements. The rules for ground-fault circuit interrupters and arc-fault circuit interrupters are located in Article 210. These two forms of protection directly correlate with 90.1 of the Code. The minimum requirements for GFCI and AFCI protection are in the interest of safeguarding persons and property (see photo 4). The inspector should verify that they are installed in locations that require this type of protection [see NEC 210.8 and 210.12].

Location and rating of service equipment


Photo 5. Service equipment and service disconnecting means to be located outside of the building or inside nearest the point of entrance (see 210.70(A)(1))

Requirements for electrical services are provided in Article 230. The number of services to a building or structure and the location of the service disconnecting means are key issues relating to the electrical service (see photo 5). In addition, there are other critical requirements for electrical services, such as equipment rating, size of service conductors, location of the service, overcurrent protection, and so on.

Grounding and bonding

Grounding of the electrical services and systems supplying the premises is another inspection must. The rules for grounding and bonding are provided in Article 250. Developing an understanding of the performance criteria and the purpose of grounding and bonding is essential for the inspector. This information is clearly provided in NEC 250.4. Effective bonding is directly related to the proper operation of overcurrent protective devices. Grounding is essential and plays a slightly different role in minimizing shock hazards and providing a means to keep conductive equipment and enclosures at earth potential, which serves to minimize shock hazards. An additional benefit of grounding is dissipation of lightning or other overvoltage conditions that might be imposed on the electrical system. Grounding and bonding circuits work cooperatively to provide essential safety and functionality of overcurrent protection during ground-fault and short-circuit events.

Overcurrent protection


Photo 6. Overcurrent devices protect the conductors and equipment on the load side of the device (see 240.4 and 240.21)

Compliance with the rules in Article 240 for the protection of electrical equipment and conductors is accomplished by proper application of overcurrent protection (see photo 6). Verification of overcurrent protection types, sizes, and locations is essential for electrical safety. Standard ratings of overcurrent protective devices are provided in Section 240.6. It is important to verify that overcurrent protective devices are applied in circuits within their short-circuit current interrupting ratings in accordance with Section 110.9.

General electrical wiring rules

Article 300 includes requirements for wiring methods for electrical installations. Essentially, these general provisions inform how to install electrical circuits, wiring methods, and equipment. Some electrical inspection essentials in Article 300 include, but are not limited to, installation and grouping of conductors of the same circuit, wiring method burial depths, protection of cables installed in walls, length of conductors in boxes, and number of conductors in boxes and raceways. Be on the lookout for crowding in junction boxes and enclosures, too many wires in raceways, and conductor protection from abrasion where necessary. These situations can lead to excessive heat and failure in time. It is important to verify that whatever wiring method is used for an installation is permitted for that particular use. Each wiring method article generally provides the restrictions on its use under the uses not permitted section (.12) of the respective article.

Conductor and cable current-carrying capacities

Verification of properly sized conductors is another electrical inspection essential. Conductors must be capable of carrying the connected load. The rules for wire sizes are provided in Article 310. Several factors impact the ampacity of conductors and cables in electrical installations: calculated loads; temperature compatibility with connected equipment, especially at terminations as previously discussed; coordination with the overcurrent protection, and compliance with product listings are some essential factors in determination of conductor ampacities.


Photo 7. Multiple NM cables bundled in a manner that requires application of appropriate ampacity correction factors (see 334.80 and 310.15(B)(2)(a))

How the conductors are installed also might require additional consideration. For example, installing conductors in higher ambient temperatures, installing multiple current-carrying conductors or cables together in a manner that they are able to dissipate heat generated by current loading. Watch for the grouping (bundling) of cables and excessive numbers of current-carrying conductors in raceways (see photo 7). Apply the appropriate correction factors and be sure that the conductor is adequate for the load and is properly protected after the correction factors are applied.

Other installations are inspection imperatives such as luminaire installations, motors and air-conditioning equipment installations and special equipment and occupancy installations as provided in chapters five and six of the Code. As previously covered in this article, this list of electrical inspection essentials is not all-inclusive. It is, however, a good starting point that provides some insight into the responsibilities and approach of the electrical inspector in verifying that installations are safe and meet the minimum requirements of the Code. Obviously, all of the Code rules are justified, and we have not visited all rules that might apply to every electrical installation. Each installation warrants its own unique challenges and is the determining factor in which Code rules are applicable.

Electrical inspection is an essential element for electrical safety for persons and property. This article has provided a glimpse of some common areas of concern for inspectors. Inspection is a big responsibility, but it is only a part of the responsibility for safe electrical installations. The primary responsibility for compliance with the Code rests with the installer and owner. The role and responsibility of inspectors is to verify compliance with requirements applicable to those installations and systems. It is equally important that installers of electrical conductors and equipment be clearly and urgently aware of the electrical installations that require most attention in the interest of electrical safety. Where there is any question about minimum requirements of the NEC, or any local code requirements, always consult the authority having jurisdiction in that particular area.


Read more by Michael Johnston

Tags:  Featured  September-October 2007 

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Strengthening Alliances in Training

Posted By Michael Johnston, Saturday, September 01, 2007
Updated: Saturday, February 09, 2013

IAEI has the principal mission of promoting electrical safety, a mission supported by the work and responsibility of the inspector. Many of the different entities in the electrical industry that strive to achieve safety by diligently carrying out their responsibilities have discovered that training is a key factor in achieving safe electrical installations.

 

Photo 1. NFPA Electrical Fire and Safety Expo in Mexico City, Mexico, in November 2006. From left to right, Alfredo Ramirez, UL; Rodolfo Aragon, NFPA; and Michael Johnston, IAEI.

 

This article looks at the importance of training, continuing education, and the three-year cycle of the NEC. This cycle necessitates effort to maintain up-to-dateness with important electrical rules. The reason is simple—electrical safety, a strong reason to stay informed. No matter what level one reaches in this business, there is always another plateau upon which new rules, technologies, methods, and systems are ever-emerging. Knowledge of the electrical business and its regulating codes and standards is the key to an abundance of opportunities.


Photo 2. Alfredo Ramirez, manager of regulatory services for Underwriters Laboratories, and Antonio Macias, director, Mexico, Central America and the Caribbean, and Michael Johnston at the Electrical Fire and Safety Expo trade show conference in Mexico.

Each organization in the industry has a responsibility and vested interest to remain up-to-date on the electrical rules we have to follow or that apply in the construction field. Each of us also has an individual obligation to remain current in our field. This takes a concerted effort to familiarize ourselves with, and to understand changes to the rules we abide by for safety. If one is deficient in understanding the requirements, electrical safety can be compromised and doing business can be more difficult and challenging. Electrical safety and the training related thereto should not be learned as one goes, but learning should be proactive, or anticipatory. IAEI takes this process very seriously and provides training that is intended to assist the industry in achieving greater understanding of the NEC rules and, more importantly, in learning how to apply those rules to systems. One such training program is IAEI’s Analysis of Changes NEC-2008. The association does its part each NEC cycle by developing material that analyzes the changes and clearly explains the meaning and impact of each change. This training material will be available in September 2007. Contact the IAEI Customer Service Department and order your copies today.

The electrical industry as a whole is gradually discovering value in establishing training partnerships. IAEI is working to grow alliances with industry partners that share common interests in providing quality electrical training. Working together with organizations such as NFPA, UL, NEMA, ICC, NJATC, IEC, ISA, and several others, IAEI brings the perspective of Code enforcement to the training arena. IAEI realizes that the value of working together with any organization to achieve common goals all comes back to electrical safety. It is difficult to oppose training, products, Code rules, safety standards, and other efforts that are driven to meet this mission of safety, which is also the mission of the association.


Photo 3. Michael J. Johnston, IAEI Director of Education, Codes and Standards networking with IAEI member Saul E. Trevino Garcia, an active electrical instructor in Mexico.

The training opportunities for IAEI are mounting, and more are on the horizon. Many regions and jurisdictions are passing laws and regulations that require qualified persons to be licensed and to receive continuing education to maintain those licenses. As one can imagine, the opportunities for continuing education providers are growing. IAEI sections, chapters, and divisions should work to provide electrical training within their geographical regions, where the opportunities are the greatest. IAEI is committed to providing the support necessary for any section, chapter, or division that is working to provide continuing electrical training. These alliances with the IAEI branches are the strength of the organization. The IAEI International Education Committee understands the importance of growing IAEI training efforts at each section, chapter, and division level. However, the training opportunities for IAEI do not stop within our own circle. These opportunities and obligations extend throughout this country and beyond.


Photo 4. IAEI member Saul E. Trevino Garcia provided a seminar on electrical systems in health care facilities.

IAEI is working to assist Mexico in growing its electrical Code and safety training. Working in cooperation with Underwriters Laboratories and the National Fire Protection Association, IAEI has renewed a presence in Mexico by providing electrical training programs and presentations, through translation, at the NFPA Electrical Fire and Safety Expo in Mexico City. Training on the NEC and other industry standards is necessary as neighboring countries work to grow their electrical safety systems. The training experience and networking in Mexico City clearly revealed that there are far greater opportunities to address electrical safety education. A large part of this collaboration resulted from the efforts of Alfredo Ramirez, manager of regulatory services for Underwriters Laboratories and Antonio Macias, director, Mexico, Central America and the Caribbean, and Rodolfo Aragon with NFPA, Mexico. These individuals continuously offer significant and unselfish support of IAEI and its mission. These gentlemen are, without question, IAEI ambassadors who are working on behalf of broadening IAEI’s reaches internationally. Their efforts have not gone unnoticed, and IAEI is committed to strengthening this important work to foster the IAEI mission internationally. As IAEI continues to expand its training and publications arm in the industry, the benefits of membership in IAEI are even more apparent. The need to extend additional training efforts beyond the boundaries of the United States will only increase in the years ahead; in fact, just recently Costa Rica has expressed interest in increasing electrical training.

Quality training requires quality instructors. Many IAEI instructors serve on NEC code-making panels, which provide for authoritative insight into the meaning of NEC rules and into how best to apply them to installations and systems. It is logical that these individuals serve as electrical instructors for the benefit of the industry. IAEI has recently invested in development of an instructor training program to equip instructors to meet these challenges. As more regions implement electrical licensing and certification requirements, the need for professional continuing education providers expands. IAEI is accredited by the International Association of Continuing Education and Training (IACET) as a qualified provider of continuing education units. Each section, chapter, and division is recognized under this accreditation. This means opportunities at all levels of IAEI for growing their own education committee work and training program offerings. IAEI training should be offered on a regular basis, over and above the regular annual meetings. Many chapters already understand the importance of activating their education committees to provide electrical Code training at the local levels and of the immeasurable benefits. Without question, each chapter or division that has started this work has realized how much more there is to do and what a great opportunity it is for IAEI to satisfy one of the basic objectives of the association, education. The records speak for themselves: In those areas where IAEI is active in education, the membership is strongest. The goal ahead for IAEI is to guide its sections, chapters, and divisions toward building IAEI training. If you are unsure of what IAEI is offering for continuing education in your group, inquire. Chances are good that there is ample opportunity for your involvement. Get involved and help IAEI make a difference.

Summary

The opportunities for IAEI education have never been greater. The International Office is doing its part by producing quality electrical training programs and by supporting IAEI sections, chapters, and divisions that are growing their training efforts locally. There is always strength in unity and in working together with other associations. IAEI is making a difference, but there is much more to do. Working with its branches, IAEI can grow while meeting the objectives our founding fathers established nearly 80 years ago. If one truly understands IAEI, the passion for electrical safety becomes clear. Safe electrical installations are the result of training, and lots of it. Again, the records demonstrate: In those areas where IAEI is active in education, the membership is strongest.


Read more by Michael Johnston

Tags:  Featured  September-October 2007 

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Can You Benefit from Roth 401(k)?

Posted By Jesse Abercrombie, Saturday, September 01, 2007
Updated: Saturday, February 09, 2013

As another year zips by, you are a year closer to retirement. Even though that day may still be a long time away, it will eventually arrive—so you’ll need to prepare for it. Will you sell your business and use some of the income from it in retirement, or will you stay on as a consultant and continue to receive pay for your services? Both are smart choices; however, they still represent taxable income. This is taxable income that most in the electrical industry want to avoid. Recently one more retirement savings vehicle has been added—the Roth 401(k).

Just like a regular 401(k), a Roth 401(k) allows you to spread your money among a variety of investments. But there are differences between the two types of 401(k) plans. When you invest in a traditional 401(k), you generally contribute "pre-tax” dollars, which means you are not taxed on your contributions today. These contributions and your earnings will be taxed when you withdraw them at retirement. Using the Roth feature in your 401(k) allows you to contribute "after-tax” dollars, which means you pay taxes on your contributions right away. However, your withdrawals and earnings will be tax-free (provided you’re at least 59 1/2 and you’ve had the account for at least five years when you retire).

Furthermore, if you leave your job, you can roll over the Roth portion of your 401(k) into a Roth IRA — and Roth IRAs don’t force you to take required minimum distributions after you turn 70 1/2, which could be a big advantage if you won’t need the money until later in your retirement years.

And here’s one more advantage of the Roth 401(k): There are no income restrictions attached to it.

I have written several times about electrical contractors and inspectors that own their own company and have had many problems with the 401k in the past when it comes to the top-heavy testing. Of course, top-heavy means they are putting away a much larger contribution than their average employee is, and Uncle Sam sends them a nice check in the mail for their money back because they failed the discrimination testing. The Roth 401k is also available in the Safe Harbor 401(k), an alternative to the 401(k), which allows business owners to contribute a lion’s share of the contribution.

Of course, you may not even choose to offer the new Roth feature in your company’s 401(k). But if it is available, shouldn’t you offer it to your employees? Before deciding, consider these factors:

  • Your age— The younger you are, the more advantageous it may be to contribute some of your 401(k) dollars into the Roth portion of your plan. As a young worker, you’ll have more years to take advantage of the tax-free earnings potential provided by the Roth feature. This additional time helps compensate for the cost of having to fund your plan with after-tax dollars.
  • Your tax bracket at retirement— Most contractors feel they will be in a higher tax bracket when they sell their business and start taking income. If you expect to be in a high tax bracket when you retire, you may find the Roth 401(k) to be particularly appropriate. The value of being able to withdraw tax-free is worth more if you’re in a high tax bracket.
  • Your willingness to divide 401(k) dollars between "pre-tax” and Roth— Your total 401(k) contributions, from all sources, are limited to $15,500 in 2007 (or $20,500 if you’re 50 or older). You could choose to put all $15,500 into either the pre-tax portion of your 401(k) or the Roth (after-tax) portion. You could also divide the $15,500, in any ratio you choose, between the two portions. For example, you could defer $7,750 into the pre-tax portion and $7,750 into the Roth portion.

Before investing in the new Roth feature of your 401(k), you may want to consult with your tax advisor and investment professional. You might only have a few years in which to take advantage of the Roth 401(k), because it will cease to be offered in 2010, unless Congress acts before then to make it a permanent fixture of the retirement planning landscape.

As long as it is around, though, the Roth 401(k) is going to be a valuable retirement savings vehicle — so think about putting it to work for you.


Read more by Jesse Abercrombie

Tags:  Featured  September-October 2007 

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Back in The Day

Posted By James W. Carpenter, Saturday, September 01, 2007
Updated: Saturday, February 09, 2013

Back when I was in high school, which seems such a long time ago now, my English teacher had our class writing a paper every two weeks. I remember after doing several papers for that class, I began to find it harder and harder to find something to write about. I had used all the stories my mother had told my sister and me about growing up on the farm and the well had run dry, or so I thought. One Sunday night I still hadn’t started on the paper that was due the next morning, and Mother got on me for procrastinating too long. So, I wrote a paper on procrastinating; I got an A on that paper. Well, here I am now trying to write another editorial for the IAEI News. After five years, maybe the well has run dry.

But wait; maybe we can look back on IAEI to when I became your CEO/Executive Director. We were just about to celebrate IAEI’s Golden Jubilee—75 years of being an association for the electrical inspectors and others interested in electrical safety. I was serving on the International Board of Directors representing the Southern Section as the section secretary/treasurer. The section secretaries were serving as the planning committee for the Jubilee, and we had delegated most of the planning and implementation to the International Office. Phil Cox, then the CEO/Executive Director, had asked the committee what we wanted the IO to do and I smartly said, "Anything we tell you.” What a mistake that was! I became the person in charge. The Jubilee was held and everyone who attended enjoyed the time at Disney World and came away with an educational experience that was talked about for a long time.

As we reminisce, other high points come to mind. After struggling financially for that first year, which was an off-code cycle year, we rebounded and had a very good year in 2004. That was when we published the Analysis of Changes, NEC-2005. That began a cycle of better times financially. After putting off dues distribution or begging the chapters and divisions to let the IO keep the distribution for a couple of times, we have recovered until distributions have been made on time for the last two years. We underwent an increase in dues, a fifty percent increase, which was difficult as any increase is. Just go up to the gas pump every week.

Membership concerns still plague us, as we can’t seem to grow. We have new members joining at a rate of 150 to 200 members a month but we can’t keep them on board. Since January 2007, we have signed up 1,204 members, but the total membership has only increased by 63. Because of the concern, the International Board of Directors has instructed the International Membership Committee to develop a program, not only to get new members, but more importantly to retain the existing members. The focus must be at the local level—member-to-member, face-to-face, local members encouraging each other to stay involved. To help with this program of involving members as active participants in IAEI, the International Membership Committee, with help from the IAEI staff, will provide training for all section, chapter, and division membership chairpersons at this year’s section meetings. There will be a two-hour session scheduled for this most important training session. Be sure that your membership chairperson attends this meeting as the very future of IAEI depends on our ability to grow the membership. "Proud to Wear the IAEI Brand”—that is a sneak preview of what is in store for the membership chairs at this training session.

I am getting away from looking back over the last five years, so let’s look at some places we have visited. My travels to section meetings had Mary Anne and me going to places that we had never been before. The Southwestern Section meetings in Hawaii; the Jubilee meeting in Orlando, Florida; the Canadian Section meeting in Halifax, Nova Scotia; the Eastern Section meeting in New Hampshire; the Western Section meeting in Traverse City, Michigan, all have a special memory for us. Of course, all the meetings at every section were enjoyable, and we have made many new friends. This year we look forward to going to other places to make new memories. Places such as Anchorage, Alaska; St Louis, Missouri; Collingwood, Canada; Scranton, Pennsylvania; Florence, Alabama; and Tucson, Arizona, are sure to be delightful, not to mention the educational opportunities that will be available. The sections in the U.S. will be exposed to the new 2008 edition of the National Electrical Code, and the Canadian members will be learning about the Canadian Electrical Code. What an exciting time!

As we continue to look back, let us compare our IAEI News to issues in the past. Many have commented on the value and the look of the News. The Publications Department staff has continued to improve the look as well as the content. We should thank all the contributors who write informative and valuable articles for the News. All our publications have improved to the point that IAEI is recognized as having the best books and training material in the electrical educational field.

Enough reminiscing! As this editorial is appearing in the September/October issue, I know all of you have made plans to attend your section meeting, and I hope to see you there. I will be there. Will you?

Read more by James W. Carpenter

Tags:  Editorial  September-October 2007 

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What Are You Paying for Electricity? Part 4, Large Commercial and Industrial Electric Rates

Posted By David Young, Saturday, September 01, 2007
Updated: Saturday, February 09, 2013

To protect your and your company’s wallets, it is very important to understand the rates you are being charged for electricity. In this segment, I am going to share with you and discuss in detail the large commercial and industrial electric rates of a typical utility. The example I am using is a utility that publishes their rates on the Internet. The electric rates you are being billed may vary greatly from my example. I recommend that you contact your utility to get a copy of your rate and to find out what other rates are available to you. Some of the terms I am using in this article have been previously defined and discussed in parts 1, 2 and 3 of this series.

Large General Service Rate

For our example utility, their large general service rate is for all customers that have a summer maximum demand of 300 kW or greater. This is the rate for most large department stores, office buildings and industrial customers. For our example utility, this rate has a customer charge of $159.63 per month. The energy charge for the summer months is 8.9571 cents per kWh for energy used during on-peak time and 6.3569 cents per kWh for energy used during off-peak time. The energy charge for the winter months is 9.5444 cents per kWh for energy used during on-peak time and 6.7667 cents per kWh for energy used during off-peak time. For this rate, on-peak hours are 6:00 a.m. to 10:00 p.m. Monday through Friday. During Daylight Savings Time (summer), on-peak hours are 9:00 a.m. to 10:00 p.m. Monday through Friday. Note that the on-peak hours during Daylight Savings Time (summer) are not just one hour different from the winter times. I find it odd that the energy rates are higher in the winter months than during the summer months.

Demand

For this rate, the demand charge is $26.128656 per kW in the summer months and $17.784842 per kW in the winter months. The good news is that the demand is a sixty-minute demand. The sixty-minute demand allows much more opportunity for load management. Note that this is not a clock-hour sixty-minute demand. It is a rolling sixty-minute demand. The metering looks for the maximum sixtyminute demand. Some utilities have a clock-hour sixtyminute demand. For this rate, the measured demand for any month is the greater of the maximum demand established during any sixty-minute period of the month during on-peak hours as measured by the demand meter, taken to the nearest whole kilowatt or one-third (1/3) of the maximum demand established during any sixty-minute period of the month during off-peak hours. You will recall that under the medium general service off-peak rate (detailed in part 3 of this series), the off-peak demand could be ten times the on-peak demand but the customer only paid for the on-peak demand. Under the large general service rate, if the off-peak demand exceeds three times the on-peak demand, the customer pays for it.


Table 1

For this rate, the billing demand for summer months (June through September) is the measured maximum sixty-minute demand for that month. The billing demand for winter months (October through May) is 25% of the measured maximum sixty-minute demand for that month plus 75% of the average of the billing demands for the most recent summer billing months. The customer pays all year long for the demands he hits during the summer. Reducing the summer maximum demand can seriously reduce the annual bill.

Power Factor

If the customer’s average power factor for the month, expressed to the nearest whole percent, is less than 90%, the customer is billed an additional 3 cents per kW for every percent the average is below 90%. So if the billing demand for the month is 500kW and the average power factor is 84%, the customer would be billed an additional 0.03 x (90 – 84) x 500 = $90.00 for that month. If the customer’s average power factor is greater than 90%, the customer receives a credit of 3 cents per kW for every whole percent between 90% and 100%. If the billing demand is 500kW and the average power factor is 100%, the customer would receive a credit of 0.03 x (100% – 90%) x 500 = $150.00 for that month. If you are not familiar with power factor, I suggest you see my article "Basic Electricity- Part 8” in the September/October 2005 IAEI News.

Annual Cost

Under this rate, a manufacturing company with demands and energy usage as detailed in the adjacent calculation will pay $283,151.04 each year. Note that 63% ($177,231.04) of the annual cost is demand charges.

Load Management

Particularly for this rate, it is easy to understand why the utility metering includes a computer. The metering has to keep track of the time of day and the day of the week including during power outages, changes to and from Daylight Savings Time, and leap years in order to keep track of power factor and on-peak and off-peak demand and energy. Load management systems are often just as complicated. Some utilities offer real-time metering data to large customers to assist in their load management efforts. With metering data from the utility metering, the customer does not have to install their own metering to accommodate load management. I have heard stories of customers who installed their own metering and found great discrepancies between their metering and the utility metering. The utility metering is usually much more accurate. Some companies have whole departments that deal with load management.

If you understand the electric rates you are paying and are willing to make changes, you can save a lot of money. With the large general service rate described above, delaying operation of some equipment to off-peak hours is an obvious savings. Reducing the summer on-peak demand should be the number one goal. Some customers purchase large generators to use as backup power sources to critical production areas and use the generators during peak production times to reduce the billing demand. Some customers shift production to nighttime to save on air-conditioning cost and to reduce the on-peak demand. With the cost of fuel and electricity going up, I am sure some companies will find innovative ways to beat the system.


Read more by David Young

Tags:  Other Code  September-October 2007 

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