When making an inspection on an electric
sign or field-installed skeleton tubing installation, where
does one begin? Well, there are undoubtedly several answers to
that question from the many inspection jurisdictions charged
with the task of adopting and enforcing the requirements of
the electrical Code. Experience has indicated that
there are a wide variety of approaches to conformance
assessment of these electrical signs and displays, or other
types of outline lighting, falling under the scope of the
adopted Code. It is best to get right to the point and
not water this down too much, because this needs to be said.
Basically there are inspection jurisdictions that are doing
the job, there are those doing part of the job, and there are
those not doing the job at all. From the enforcement
perspective, this lack of consistent and uniform enforcement
of the minimum Code rules for electrical signs and
outline lighting installations has lead to installations that
are often less than code-compliant to put it mildly. This
article will serve as a small reminder of the role we share in
achieving electrical safety in these types of installations.
If you are involved in electrical inspection, you might decide
to critique your approach to inspections of electrical sign
displays or field-installed skeleton tubing installations, or
how your jurisdiction requires these types of electrical
safety inspections to be handled. Although administrative and
procedural policies will vary from one jurisdiction to
another, our goal for the technical enforcement of these
installations should be very consistent and uniform. This will
possibly be like breaking new ground and involve change, which
society is more often than not naturally resistant to. More
than likely, there are many challenges and much work to be
done in this area. The amount will vary from one area to
another and often involves becoming more knowledgeable by
acquiring additional training, in many cases for inspectors as
well as installers. It also requires developing and
maintaining open and effective working relationships with the
electrical sign industry.
IAEI is an organization with a primary
concern for electrical safety. The association is also
interested in consistent and uniform enforcement of the
applicable electrical codes and standards. Establishing good
solid working relationships is an important part of helping in
this area. It can be said, without a doubt, that installing
contractors, owners, and inspectors all desire the electrical
installations to be safe. Meeting the minimum requirements of
the applicable electrical and building codes is an essential
element, and in those areas or regions that adopt the National
Electrical Code into law, it is required.
Let’s take a look at some of the basic
requirements contained in Article 600 of the NEC that
can assist enforcement officials in carrying out their
responsibilities in attaining code-compliance in these areas.
The first section of Article 600 provides the scope of
coverage. Clearly within the scope one can identify the type
of electrical signs and outline lighting installations that
the rules in the article apply to. The article contains rules
for installations of conductors and equipment for all
electrical signs and outline lighting installations.
Those installations that include the use of
neon tubing—such as signs, decorative elements, art forms,
or skeleton tubing—are covered by rules in Article 600 (see figure
1 and photos 1 and 2). So,
basically, all electrical signs, displays, and most outline
lighting installations are covered by the rules in Article
600. It should be emphasized that there are outline lighting
installations that can be installed using luminaires (lighting
fixtures) that are wired in accordance with the rules in
chapter 3, as well as other applicable requirements in
chapters 1 through 4, such as grounding and bonding in chapter
2, connections and mounting of equipment in chapter 1, and the
rules for luminaires (fixtures) found in chapter 4. When
applying the requirements of the Code, it is often
helpful to develop an understanding of defined terms to assist
with correct application of the rules to electrical
installations and systems. It is no different when it comes to
electric signs and neon installations.
Terms to Know
There are many essential definitions contained in Article 100
that apply to sign installations such as wet locations, dry
locations, listed, labeled, and several others. There are a
few specific and key definitions provided in Section 600.2
that provide additional information to assist in proper
application of the rules.
Electric-Discharge Lighting. Systems of
illumination utilizing fluorescent lamps, high-intensity
discharge (HID) lamps, or neon tubing.
Neon Tubing. Electric-discharge tubing
manufactured into shapes that form letters, parts of letters,
skeleton tubing, outline lighting, other decorative elements,
or art forms, and filled with various inert gases.
Section Sign. A sign or outline
lighting system, shipped as subassemblies, that requires
field-installed wiring between the subassemblies to complete
the overall sign.
Sign Body. A portion of a sign that may
provide protection from the weather but is not an electrical
enclosure.
Skeleton Tubing. Neon tubing that is
itself the sign or outline lighting and not attached to an
enclosure or sign body [NFPA 70 600.2].
The definition of section sign is
included in Section 600.2 to provide a description of one
particular type of listed electric sign discussed in Section
600.12. Signs are usually required to be listed as indicated
in 600.3 and can be manufactured in various forms. Three of
the most common forms include an all-in-one electric sign with
one listing mark, listed section sign delivered to the site in
sections (subassemblies) and assembled on-site (including
connections and field wiring between sections) and then
installed as a complete sign. Another very popular listed
section sign is shipped to the site in sections or
subassemblies and installed, but the sections are remote from
one another.
This type of section sign requires
field-installed wiring between the sections and the associated
power supplies or transformers (see figure
2 and photo 3).
It is important to note that even though each section of the
overall section sign is listed, the field-installed secondary
wiring must be verified by the AHJ for compliance with any
installation instructions and applicable provisions of Article
600 that could, and often does, include some of Part II of
Article 600. Field-installed secondary wiring includes the
wiring method used, the type of fittings for the particular
wiring method, and grounding and bonding provisions. All of
these field-installed materials associated with listed
sections signs must be verified for compliance with the
required manufacturer’s installation instructions as well as
applicable Code requirements. The definition of section
sign should assist installers and the enforcement community by
providing clarification as to the rules that apply to these
listed signs that are beyond the scope of the product standard
UL 48 Standard for Electric Signs.
The Approval
Process
It is a general requirement that all electrical conductors and
equipment required or permitted by the Code be
acceptable only if approved (see NEC 110.2). Approved is defined in Article 100 as "acceptable to the authority
having jurisdiction." Listed products and listed
equipment assist the approving authorities in carrying out the
responsibilities of approvals. As a rule, inspectors utilize
product listing, labeling, and evaluation by recognized
electrical testing laboratories as a basis for approvals of
equipment used in electrical installations (see the
information provided in NEC 110.3(A) and 90.7). Listed
electric signs and accessory products should bear a listing
label (see figure
3 and photo 4).
Generally, if there is a product standard to which electrical
products can be evaluated for safety and listed, the
enforcement community requires them to be listed. These are
basic requirements contained in chapter one, which apply by
and large across the entire Code. With electrical signs
and outline lighting more specific requirements appear in
Article 600. Section 600.3 specifically requires electric
signs, section signs, and outline lighting to be listed and
installed in conformance with that listing, unless otherwise
approved by special permission. This specific listing
requirement makes the task of attaining code-compliance in
these installations much easier. By requiring electric signs
and outline lighting to conform to this listing requirement,
the installations will be more uniform and should more
consistently qualify for approval. The term special
permission is defined in Article 100 as "the written
consent of the authority having jurisdiction." Special
permission is sometimes necessary and utilized in the approval
process for installations covered within the scope of Article
600 but is unique in nature, or, perhaps, includes unique
characteristics or features for which Code rules have
not yet been developed. Field-installed skeleton tubing
installations, on the other hand, are not required to be
listed, but they are required to meet the requirements of the Code. Part II of Article 600 provides many special requirements
for these types of installations. It should be noted that
outline lighting can consist of listed luminaires (lighting
fixtures) that are wired in accordance with chapter 3 of the Code.
Special permission is often issued by the
building safety departments in the form of a modification or
variance, but always must be in writing. Generally, the
details and specific criteria of how the unique installation
meets the equivalent and effective safety desired for the
particular situation are provided as part of this documented
and written special permission. The method used in granting
special permission can vary from jurisdiction to jurisdiction.
Each will have particular policies or procedures for granting
approval by special permission.
Manufacturer’s
Installation Instructions
As provided in Section 110.3(B), "listed or labeled
equipment shall be installed and used in accordance with any
instructions included in the listing or labeling." Listed
and labeled equipment usually includes installation
instructions either labeled on the equipment or separately.
Inspectors enforcing this requirement are well on their way to
attaining code-compliance and being able to issue confident
approvals of these types of installations. Most listed signs
including listed section signs are required to include
installing instructions in accordance with the product
standard. Inspectors should be requiring these installation
instructions and using them in the inspection process.
Installers should also be using them to complete the
installation. This has a built-in feature of bringing both the
installer and inspector to the same page, so to speak. The
field-installed wiring associated with listed section signs
must also meet any other applicable requirements of the Code.
It seems that this would be a fairly simple
rule to comply with, but the reality is that it is a rare,
rather than popular, method of issuing an approval of these
types of equipment and installations. Ask for listed products
and verify that they are being used and installed in
accordance with the listing. It seems fairly clear, yet so
many unlisted electric signs, and associated unlisted
electrical sign accessory products are installed and in use in
the field. The sign and outline lighting installation
community all want their displays safe and code-compliant.
Understanding that inspectors generally rely heavily on the
use of listed products as a base their approval should be a
strong encouragement for using them. Yet still there are
numerous unlisted electrode enclosures (boots), unlisted
nonmetallic tubing, and other inadequate parts being used in
the high voltage secondary installations associated with these
displays. These inadequate and unevaluated products are often
found to be primary contributors to the infamous and all too
common failures of these systems. Many quality electrical sign
installers and contractors know and understand the value of
using listed materials and equipment that they can stand
behind with confidence. Often sign installers learn this in
the school of hard knocks. For field-installed skeleton tubing
installations, the general concept of requiring listed
products and components to be installed is of great assistance
to installers and goes a long way in getting the green tag
approval from the approving authority. The only other
challenge, once listed products and components are used, is to
be sure that they are used within the limits of how they were
evaluated and intended to be used. For example, an electrode
enclosure (boot or glass cup) that is listed for dry or damp
locations would be unacceptable if used inappropriately in a
wet location and, certainly in most cases, welcomes unwanted
failure (see figures 4 and 5).
Failures in high voltage secondary circuits can and do cause
fires. This is another real important reason to use the proper
products for the job, and ensure that the minimum requirements
of the Code are met. Electricity is a powerful force
and can cause serious and costly damage if not handled
properly.
Electric Sign
Marking Requirements
The Code, in addition to the applicable product safety
standard, requires a minimum amount of markings (labels) on
electric signs and outline lighting systems. These required
marks on this equipment also provide needed information for
the approval process. It still is amazing the number of
electric signs and outline lighting systems that are not
labeled as required by the Code and applicable product
standard. The required markings must provide the following
minimum information:
-
Manufacturer’s
name, trademark, or other means of identification
-
Supply (input) voltage
required and current rating
Signs and outline lighting systems
incorporating in-candescent lampholders are required be
marked with the maximum allowable wattage of the lamps, and
these markings shall be permanently installed, in letters at
least 6 mm (¼ in.) high, and must be located where visible
during the relamping process [see NEC 600.4(A) and
(B) and figure
6 and photo
5].
Branch Circuit
Requirements and Ratings
Each commercial building and commercial occupancy accessible
to pedestrians is required to be provided with a minimum of
one outlet for sign or outline lighting system use. This is
not a receptacle that is required but an outlet (see the
definition of outlet in Article 100). This outlet must be
located in an accessible location at each entrance to each
tenant space. It should be noted that the Code does not
recognize service hallways or corridors as accessible to
pedestrians for the purpose of proper application of this
section. The required outlet(s) shall be supplied by a minimum
of one branch circuit rated at not less than 20 amperes. This
branch circuit is not permitted to supply any other load(s).
Branch-circuit ratings for electric signs
are required to meet the following minimums:
1. Branch circuits that supply signs and
outline lighting systems containing incandescent and
fluorescent forms of illumination shall be rated not to exceed
20 amperes.
2. Branch circuits that supply neon-tubing
installations shall not be rated in excess of 30 amperes.
The wiring methods used for the branch
circuit(s) supplying electric signs and outline lighting
systems must meet the applicable requirements of Sections
600.5(C)(1), (C)(2), or (C)(3). The wiring method used to
supply signs and outline lighting systems is required to
terminate within a sign, an outline lighting system enclosure,
a suitable box, or a conduit body. The wiring method should
include an equipment grounding conductor as specified in
250.118 for grounding the sign or system and meeting the
general requirements of 600.7. This method of grounding should
be verified by field inspectors, even on listed signs. Tight
mechanical connections, made in a workmanlike manner at
fittings terminating in sign enclosures, are important in
maintaining an effective ground-fault current path. If the
equipment grounding conductor is of the wire-type, the
connection of the conductor to the enclosure must be made in
accordance with 250.8 using listed pressure connectors, listed
clamps, or other listed means. Sheet metal screws are not
permitted to be used to connect grounding or bonding
conductors or connection devices to enclosures. This is a
common problem in the field and verification of the grounding
conductor connection should be part of any thorough inspection
process. This is an important safety circuit. The branch
circuit supplying signs, per NEC 90.3, must coomply
with the general rules in chapters 1–4 unless they are
supplemented or modified in Article 600. An example of
requirements that are modified can be found in Section 600.7;
600.32(A)(4) and (A)(5).
Wiring in Sign
Enclosures
Signs and transformer enclosures are permitted to be used as
pull or junction boxes for conductors supplying other adjacent
signs, outline lighting systems, or floodlights that are part
of a sign, and shall be permitted to contain both branch and
secondary-circuit conductors. It should be emphasized that
there are clearance requirements for high-voltage secondary
conductors Secondary conductors of field-installed skeleton
tubing installations must be separated from each other and
from all objects other than insulators or neon tubing by a
spacing of not less than 38 mm (1½ in.) as provided in
600.32(E).
Where metal or nonmetallic poles are used
to support electric signs, the pole is permitted to enclose
supply branch-circuit conductors, provided the poles and
conductors are installed in accordance with requirements of
Section 410.15(B).
Other Requirements
As indicated in the beginning of this article, only some of
the basics of inspections of signs and outline lighting
systems are covered here. Essentially the equipment covered
within the scope of Article 600, listing and marking
requirements, approvals, and the requirements for branch
circuits are discussed in this writing. There are many other
requirements contained in Article 600 as well as other parts
of the NEC that must be applied in the inspection
process, such as the required disconnecting means for the
special equipment covered in 600.6; grounding requirements as
provided in 600.7; locations including wet locations as
provided in 600.9; and enclosure requirements as covered in
600.8. Although field-installed skeleton tubing installations
are not required to be listed, listed parts and components are
available for constructing and installing these systems.
Requiring the use of listed parts and components in these
installations is helpful in attaining compliance and is a
useful tool in the approval process of these installations.
Parts I and II of Article 600 apply to these installations.
Summary
The primary objective of this article is to raise the level of
awareness of inspectors and emphasize the importance of
electrical inspections of electric signs and outline lighting
systems. The enforcement community has an important role in
electrical safety; and to be effective, inspections must be
made. Inspectors have requirements built into the NEC that can be of substantial assistance in attaining
code-compliant electric sign and outline lighting systems.
With the specific requirement for listing, as indicated in
Section 600.3, the approval process becomes much more
manageable for the enforcement community. Requiring listed
signs and outline lighting systems is step one. The next steps
should be to assure compliance with any installation
instructions included in the listing and to verify that the
equipment is being used within those limits. For any
field-installed portions of listed electric signs and outline
lighting systems, be sure that all other applicable NEC requirements are met. Know how and when to utilize special
permission in the approval process. Typically, special
permission is utilized in the approval process on a limited
basis. Field-installed skeleton tubing installations are not
required to be listed but are required to meet all of the
applicable provisions of Parts I and II in Article 600. Also
any field-installed wiring methods must be in accordance with
the applicable provisions of chapter three, such as supports
and securing requirements. The authority having jurisdiction
is responsible for interpretations of the Code rules
and approvals. It is important to understand that listing is
not an approval, but it usually serves as the primary basis
for the full approval process. If there is no inspection,
there obviously is no approval. Seems like a fairly elementary
concept or process to implement, yet there continues to be an
enormous amount of noncompliant electric sign and outline
lighting displays out there. The requirements of the NEC are the minimum, which basically means one needs to do at
least that much. Still it seems like there is so much work to
be done in this area. This article is based on the rules
contained in the 2005 edition of the National Electrical
Code and does not include any local amendments or code
requirements.
Michael J. Johnston is IAEI’s
director of education and an IAEI principal member on
CMP-5. Johnston was formerly employed as an electrical
field inspections supervisor for the city of Phoenix,
Arizona. He is fully certified in many areas. He is a
member of the IBEW. He achieved both journeyman E-2 and
master electrician E-1 licenses in the state of
Connecticut. Additionally, he holds all IAEI
certifications. He also holds ICC Electrical Inspections
Certification. He is a member of the UL Electrical
Council. |
