Article 410 

 

 

 


In this section of the module we will cover some to the crucial code requirements for fixture installation. This is not intended to be a formal interpretation of the NEC. It is meant only to assist you in understanding the NEC. We will only discuss certain parts of Article 410. You should read the entire article and make a note of any questions. E-mail these questions to smitty@electrical-experts.com. We will respond to your questions with in one business day.

 

Some of the articles listed will be marked with a highlighter. For example 410.1 or 410.4(D) We have provided these marks as suggestions of areas you may wish to highlight in your codebook for future reference. I do not suggest highlighting your code book while studying for an examination. You will not be able to use a highlighted code book in many states. We have used separate colors to maintain distinctiveness. We have used Yellow for general information, Red for often used material, Green for issues of grounding or polarity, Purple for things only applying to dwelling units and gray to indicate a code change.  You of course must determine your own color coding system.

Part I General

 

410.1 Scope. Article 410 covers the installation and construction requirements for lighting fixtures, luminaires, lampholders, pendants, incandescent filament lamps, arc lamps, electric-discharge lamps, recessed fixtures, special application fixtures, and outside lighting fixtures. The 2008 NEC has added portable luminaires to this list also.

This article applies directly to field installations on a daily basis and also contains several requirements for manufacturers of lighting systems.

 

410.2

The NEC style manual requires the words that are used in a single article and require definition shall be defined in the .2 section of the article. The 2008 NEC has included two new definitions. Closet Storage Space: This definition clearly defines what closet storage space is and includes the diagram that was formally located in 410.16. This definition should help enforcement authorities with interpretation issues.

Lighting Track: A definition of lighting track has also been supplied.

Table 410.2 Closet Storage Space

 

 

410.5 contains a very important rule. Luminaries, lampholders, portable luminaires and lamps shall have no live parts normally exposed to contact. The word normally implies after installation is complete and all lamps, fittings and fixture parts have been installed. Obviously a lampholder will have access to exposed live parts before the lamp is installed, this would not classify as normally. This article also states that the metal terminals, which may be exposed for attachment, must not be placed in the fixture canopy or the base of a table or floor lamp. These requirements primarily apply to manufacturers although it is good for an electrician to know these provisions. Often customers may desire an electrician to install custom made fixtures. The electrician should be aware that the fixture must meet certain criteria.

 

Part II Luminaire Locations

 

410.6 Requires that all luminaires and lampholders shall be listed. This means they must be tested and listed with a nationally recognized testing laboratory, such as Underwriters Laboratory.  

410.10 Gives requirements for luminaires installed in four specific locations.  

 

 

Wet Locations: 410.10(A)

The opening statement is very important. It states that it is the electrician’s responsibility to ensure that fixtures installed in wet locations are installed so that water cannot enter or accumulate in wiring compartments. This section also requires the fixture to be marked for such use. It is important to note the NEC does not require these fixtures to be “listed” however you will find that most electrical inspectors will have this requirement. The NEC does not require it because the first sentence puts the responsibility on the electrician to install the fixture so that water can not enter the fixture.

 

Corrosive Locations 410.10(B)

A simple one sentence statement requires that the fixtures used n this location must be suitable for the location. This is left completely to the responsibility of the electrician. There is no requirement for listing or marking here. Electricians should be careful to document the fixtures used in these locations with manufacturers information and cut sheets.

 

In Ducts or Hood in Commercial Kitchens  410.10(C)

This section contains specific requirements for fixtures installed in commercial kitchen hoods. These fixtures will be exposed to extreme temperature variations, water, grease and possibly flame. They must be able to withstand this environment. Imagine the problems cause by a lamp in a commercial exploding because of temperature exposure over the cooking area of a kitchen during the lunch hour rush.

Note: A standard gasket type luminaire is not permitted because the heat will cause the gasket to fail and ruin the seal.

 

Above Bathtubs and Showers  410.10(D)

No part, highlight No part , of a cord-connected fixture, hanging fixture, lighting track, pendant fixtures or suspended ceiling paddle fans can be located within 3 ft horizontally and 8 feet vertically from the top of the bathtub rim or shower threshold. This is why we typically install recessed can with water resistant sealed trims in showers. This rule does not apply ot surface mounted fixtures.  Of course any fixture used in this space would also follow under the requirements 410.4(A) since this area would be classified a damp or wet location. The purpose here is to reduce the exposure of the person to possible exposed and energized parts and also to reduce the chance of electrical current conduction through water condensation on these types of fixtures. Fixtures installed within the actual outside dimension of the bathtub or shower enclosure shall be listed for damp location and if subject to shower spray for wet location.

 

410.16 Clothes Closets contains requirements for the location  and installation of fixtures in the clothes closets. This rule is not limited to dwelling units but is most often applied there. I do not recommend highlighting in the dwelling unit color because the rule also applies to non-dwelling units.

 

The definition of closet storage space has been moved to 410.2 from this section. The primary change to this section in 2008 was the addition of LED luminaires to the allowed list of luminaires in a closet storage space.

 

 

410.8(16) Fixtures Permitted in Clothes Closets

Only the following types of fixtures may be install in clothes closets.

 

 

 

410.16(C) Fixtures with exposed or partially exposed lamps and hanging type fixtures are specifically prohibited.

 

410.16(D) Location of the Fixtures

Part III Provisions at Fixture Outlet Boxes

 

410.22 Outlet Boxes to be covered. All outlet boxes shall be covered with a cover or a fixture. This is to reduce the chance of incidental contact with exposed live parts and to help contain any fire or blast that may occur in an outlet box.

 

410.24 Connection of Electric Discharge Fixtures

To help you better understand this section we have include a glossary of some of the terms used concerning lighting.

 

Glossary of Lighting Terms
Ballast — transforms and controls electrical power to the light. A device used with an electric- discharge lamp (for instance, fluorescent lamps) to obtain the necessary circuit conditions for starting and operating.

Compact Fluorescent Light Bulbs (CFLs) — (See Fluorescent Lamps) — Small-diameter fluorescent lamps, folded for compactness. Some feature a round adapter, allowing them to screw into common electrical sockets and making them ideal replacements for incandescent bulbs. Newer fixtures allow CFLs to be plugged in directly without the round adapters. CFLs are designated as T-12 or T-8; T-12's are 1.5 inch in diameter while T-8's are 1 inch in diameter. Lamps that are thinner block less of their own light.

Electronic Ballast — Electronic ballasts convert power to light more efficiently than older magnetic ballasts and provide the same amount of light while reducing energy use up to 25%. Electronic ballasts represent a major step forward in energy-efficient lighting, offering savings in cost, energy, and pollution. Typically, electronic ballasts require bulbs designed for use with this type of ballast.

Fixtures — Devices that contain the bulbs and (if necessary) the ballasts. Fixtures come in hundreds of shapes and sizes depending on their application. Some are designed to give architectural appeal and provide ambiance, and some are specially designed to minimize glare on computer screens and other working surfaces.

Fluorescent Lamps — Low-pressure-mercury electric discharge lamps in which a fluorescing coating transforms some of the ultraviolet energy generated into light. Although fluorescent lamps are often associated with a harsh white light, lamps that simulate natural daylighting and incandescant light are now available. These are often rated by the color temperature, and color rendering index. See Compact Fluorescent Light Bulbs.

High Intensity Discharge Lamp (HID Lighting) — An electric discharge lamp, including groups of lamps known as mercury, metal halide, and high pressure sodium. The major portion of the light is produced by radiation of metal halides and their products of dissociation-possibly in combination with metallic vapors such as mercury.

Incandescent Lamp — A lamp in which light is produced by a filament heated to incandescence by an electric current. Typical light bulbs are incandescent lamps. These bulbs are typically very inefficient, converting only about 10% of the energy to light--the rest is transformed into heat.

Light (photo) Sensors — are used to integrate the building's electric lighting system with its natural daylighting system, so that the lights go on only when daylighting is insufficient.

Motion Sensors — are used so that the lights go on when someone is in the space. These save energy by not depending on people to turn lights off as they leave a room. They also provide convenience and security when used for outdoor lighting, while minimizing the use of the lighting.

Troffer — A recessed lighting fixture installed with the opening flush with the ceiling.

 

Based on these descriptions we can see that electric discharge fixtures are more commonly referred to as fluorescents and HID fixtures.

410.24(A) states that electric discharge luminaires may be mounted independent of an outlet box even though they are not designed as a pendant fixture. It also states we can connect the fixture through flexible cord or MC, AC or MI cable and Romex.

410.24(B) contains a very important requirement. If a fluorescent, surface mounted fixture is mounted on top of a recessed or concealed outlet box an access panel must be located within the fixture to allow access to the outlet box. This means that we cannot mount a fluorescent fixture over a box in the ceiling and just put a chase nipple on the fixture to pull the wires into the fixture. That would not allow access to the wiring in the box.

Part IV Fixture Supports

Part IV contains the requirements for supporting fixtures.

 

410.30(A) simply states that the screw shell of the fixture and nothing else may support any fixture that is less than 16 inches in diameter and weighs less than six lbs. The screw shell of the fixture is that part of the fixture shown in the diagram below.

 

 

It is most often referred to as the lamp holder or socket. The NEC does not refer to them in this way because these terms may be applied to other devices as well. This also requires that fixtures of greater than 16-inch diameter or which weighs more than 3 pounds must be supported in other ways. This can be done by screws to the outlet box or by an independent means of support.

 

410.30(B) contains the requirements for supporting fixtures on metal poles. Any metal pole may be used to support a fixture if the pole is not used as the raceway for the conductors. If the pole is also going to serve as the raceway for the conductors, the following conditions must be met. Highlight the statement “and as a raceway” to help you remember this.

 

410.36 Means of Support

410.36 details the allowable methods for supporting fixtures. This section should be used in conjunction with 300.11 to better understand the requirements.

 

410.36(A) refers the reader to article 314.23. Stop and read all of 314.23 before continuing. We also want to take this opportunity to have you look at Article 314.27, which certainly pertains to our subject. Return here when finished.

This section simply states that a fixture may be mounted on any outlet box meeting the requirements of 314.23.

 

410.36(B) contains the requirements for supporting fixtures in suspended ceilings. These parts of the NEC’s requirements are less stringent than some local authorities allow.  The NEC requirement for supporting fixtures in a suspended ceiling is tow fold.

  1. The fixtures may be supported by the suspended ceiling members (grid) if:
    1. The grid pieces are securely fastened to each other
    2. The grid is securely attached to the building structure at appropriate intervals.
    3. The fixtures must be fastened to the grid with listed and identified clips, bolts, screws or rivets.
  2. The fixtures may be suspended from ceiling wires that are independent from the ceiling support wires. This allowance is located in 300.11(A)and (B).
    1. The independent ceiling wires may support the fixture.
    2. The ceiling wires must be secured at both ends.
    3. The independent ceiling wires must be distinguished from the ceiling support wires. This is most easily achieved by painting the wires prior to installation a distinctive color.

 

Note: Many AHJs require both the attachment of the fixture to the grid and the suspension from ceiling wires. Some AHJs also have specific rules concerning the methods of attachment and the method of suspension. For example: Some AHJs do not accept the “hurricane clips” on fixtures as a listed and identified clip because no specific identification is located on the fixture. Some AHJs require a ceiling wire on all four corners of the fixture and others require one wire each on tow opposite corners. Only one of theses requirements is located in the NEC. The NEC does require the clips to be listed and identified. The NEC requires only attachment to the grid OR suspension by ceiling wire, not both.

 

I suggest making a note at 410.16(C) to reference you to 300.11(A) and (B).

           

 

410.36(G) states that trees may be used to support fixtures. This section contains two FPNs. The FPNs refer you to 225.6, which has the requirement overhead conductors may not be supported by trees. This includes the final means of attachment. In other words: A fixture mounted on a tree cannot be fed with overhead conductors.

The second FPN refers you to 300.5(D), which lists the requirements for protecting conductors that are directly buried. This is understandable since this is the only means of feeding a fixture mounted to a tree.

 

Part V Grounding

 

Part V contains the requirements for grounding fixtures. These requirements are the standard grounding requirements for all equipment. Basically all exposed metal parts must be grounded and the fixture must provide a means for attaching an equipment grounding conductor and the fixture must be connected to an equipment grounding conductor.

 

410.42(A) contains on exception to the requirements above. Lamp tie wires, mounting screws, clips, and decorative bands on glass spaced at least 38mm (1 1/2”) from lamp terminals shall not be required to be grounded. This allowance was added to so that the electrician did not have to make sure an effective bond existed at the point of attachment to the ceiling wire or screw supporting it and also so that a bonding jumper did not have to be run to the decorative metal bands on the trim of the glass canopy or shade.

 

 

Part VI Wiring of Fixtures

 

Part VI contains the specific rules on the installation of the wiring in and to a light fixture. We suggest reading all of Part VII . We will point out some of the highlights in this part of the module.

 

410.48 states that all conductors in a fixture must arranged neatly. This is important for future maintenance and to protect the conductors. I am sure you have opened some fixtures that were obviously wired by someone who should have been more familiar with this requirement. Do not make the same mistake. Someone may someday be looking at your work. Let them know you are a professional. This section also states that conductors must be installed so as not to exceed their temperature listing. This is done by keeping conductors away from ballasts and lamps as much as possible and being sure to always use a conductor with a high enough temperature rating for the application.

 

410.50 states that the fixture leads must be attached so that grounded conductor is attached to the screw shell of the lampholder and the ungrounded conductor is attached to the pin at the base of the screw shell. If the reverse is done, the possibility exists of an electrical shock occurring while removing or installing the lamp. This one is really important.  We recommend underlining this one also. Make it really stand out..

 

410.56(F) states that the conductors must be installed in such a manner that the weight of the fixture does not put tension on the conductors. A strain relief may have to be used in some cases to meet this requirement.

 

 

Cord Connected Showcases

 

Many retail establishments use cord connected showcases such as the ones used in jewelry departments. These showcases are rarely fastened in place and are cord connected. This allows the owners to rearrange the store. These showcases are also equipped with a receptacle outlet at each end of the base. These receptacles, despite popular opinion, are not for plugging in cash registers and calculators. They are for connecting together showcases. Section 410.59 (A) through (E) lists the specific requirements for this type of installation.

  1. The showcases may be fed from a permanently installed receptacle by means of a flexible cord.
  2. Up to six showcases may be fed from the same permanently installed receptacle and then “daisy-chained” together using flexible cords.
  3. The flexible cord must of the hard service type. Some examples of hard service type cords are :
    1. G
    2. HSJ
    3. S
    4. SC
    5. SE
    6. SJ
    7. SO

Note: Details about these cord types can be found in Article 400. 4. The most common type used is SO cord.

4.      The flexible cord must have an equipment-grounding conductor sized in accordance with 250.122.

5.      The receptacles must be of the 15 or 20-ampere type only.

6.      The flexible cords must be secured to the underside of the showcase to prevent physical damage.

a.       The spacing between showcase can be no more than 2 inches

b.      A free lead at the end of showcase assembly must have a female attachment, which does not extend beyond the case.

7.      The distance from the first showcase to the permanent receptacle must be more than 12”.

8.      No other equipment or devices may be connected to the showcases. Nothing.

9.      The fluorescent light fixture with in one showcase may be daisy chained from single ballast but this secondary wiring must be limited to a single showcase. In other word. Each showcase must have at least one ballast for the fluorescent fixtures.

 

These are fairly straightforward rules. Be sure your retail customer is aware of them. They will need additional receptacles at the showcases for equipment and they may want to consider installing some additional floor receptacles to give them some flexibility to move the showcases in the future.

 

410.64 states that fixtures may not be used as a raceway for conductors, unless the fixture is listed and marked for the purpose. See the diagrams below.

 

 

 

 

 

 

 

 

 

 

 

 

 


410.65 is a follow up to 410.64. It states that designed for end-to-end connection to form a single fixture or fixtures connected together by EMT., Nipples, MC or any other recognized wiring method may contain a two wire or one multi-wire branch circuit feeding the fixtures and not listing or marking is required these fixtures. This article also allows for an additional branch circuit for an emergency circuit. The diagram above is legal without marking and listing if the “other equipment” is removed at the end of the circuit.

 

Parts VII, VIII, IX and X

The above listed parts contain requirements primarily concerning the manufacture of fixtures. We suggest reading this material. We will not discuss these parts in this module.

 

Part XI Special Provision for Flush and Recessed Fixtures

 

Part XI lists the special requirements for flush mounted and recessed fixtures. Most of these requirements are designed to eliminate the possibility of the fixture causing a fire from being in contact with flammable material such as wood or insulation. Fixtures generate a great deal heat as anyone who has ever removed a 60 watt light bulb without allowing it to cool knows. This same heat, which can burn your hand, can also start a fire if certain precautions are not taken.

 

410.115(A) requires that all fixtures install in combustible materials be installed so that the materials next to the fixture will not be exposed to temperatures in excess of 90 degrees centigrade or 194 degree Fahrenheit. This includes sources of heat both outside the fixture and the fixture itself. This requirement is best met by using fixtures that are rated at 90 degrees centigrade. A fixture is designed to operate at temperatures lower than it’s rating.

 

410.115(C) requires recessed fixtures using incandescent lamps to be thermally protected. This means the fixture must be labeled by the manufacturer as “Thermally Protected” or “Inherently Protected” and designed with same characteristics as a fixture labeled “Thermally Protected”. This labeling must be on the fixture itself. Having documentation stating the fixture is thermally protected is not enough to meet this requirement. A fixture which is designed to be used in poured concrete and is used in poured concrete does not have to meet this requirement.

 

410.116 divides recessed fixtures into two categories; Non-type IC and Type IC fixtures. The IC rating was developed by fixture manufacturers to identify fixtures that were specifically designed to dissipate heat rapidly and did not require free air space around the can to dissipate heat. These Type IC fixtures can therefore be completely covered by blow in insulation and suffer no adverse heat affects. A fixture without this rating will quickly overheat if covered by insulation even partially.

 

410.116(A)(1) states that a fixture that is not identified as an IC fixture must be installed so that all recessed parts are not in contact with combustible material. At ½” space must be maintained from any combustible material. Please note this requirement is for any combustible material and does not include insulation.  410.116(B) further requires that insulation must be kept at least 3” away from the fixture or any of its parts. Simply moving the insulation away form the fixture at the time of installation will not be enough to meet the requirements of this section. A barrier must be installed to prevent the insulation from coming into contact with the fixture.

 

410.116(A)(2) allows a fixture with an IC rated fixture to be installed in contact with combustible material and to be completely covered by insulation. A type IC fixture will have the letters IC permanently marked on the fixture by the manufacturer.

 

Part XIII Special Provisions for Electric-Discharge Lighting Systems of 1000 Volts or Less

 

This part of the article contains the requirements for HID and fluorescent fixtures operating at less than 1000V. This parts contains many requirements. We recommend you read the entire part. We will concentrate on some requirements the ballasts of fluorescent fixtures.

 

410.130(E) requires the ballasts for fluorescent fixtures installed indoors to be thermally protected. They must be labeled as such and the protection must be built into the ballast. These ballasts must be replaced periodically and the NEC specifically points out that the replacement ballast must also be thermally protected in the same manner. There are also three exceptions to this requirement. These are not defined as exceptions in the NEC, rather they are part of the requirement.

 

410.130(E)(2) states that a simple reactance ballast providing energy for simple straight tube fluorescents does no have to be thermally protected. These types of fixtures are most often seen in industrial applications.

 

410.130(E)(3) is very important. This section requires that the ballast of a fluorescent exit light not be thermally protected. This is because an overload or overheating situation could result in the fixture to stop operating which would create a greater hazard.

 

410.130(E)(4) requires the same thing of fluorescent fixtures used for egress lighting.

 

It is important to note the requirements for exit lights and egress lights are not optional. These types of fixtures must not have thermal protection.

 

410.130(F) requires that HID fixtures be equipped with thermal protection.

 

410.130(G) requires a disconnecting means to be installed on or in all florescent fixtures other than those in dwelling units that have ballasts that can be serviced in place and utilize double ended lamps. It is important to understand all the requirements of this section and Recommend reading all of 410.130(G) before making any fluorescent fixture installations. Most manufacturers are now including this disconnecting means in the fixture wiring. Be sure to train your people not to remove this quick connector as that will violate this requirement unless you are going to put another means of disconnect in the fixture.

 

 

Part XV Lighting Track

 

 

The primary requirements are that lighting track must be a manufactured assembly. The length of the track may be adjusted by adding and removing sections of track. This requirement in 410.100 should be highlighted. This means an electrician may not cut a piece of lighting track to make it smaller.

 

410.151(A) also requires that the track be permanently installed and only lighting track fittings be used with the track. A further restriction prohibits general-purpose receptacles from being attached to track lighting.

 

410.151(C) provides a list of all the places that track lighting may not be used. Electricians must pay careful attention to this list when installing track lighting.

 

410.151(D) prohibits fittings from one type of lighting track being used on another type of lighting track. The fact that the fitting may work fine and fit perfectly is a mute point. It is not allowed. They shall also be installed so that they maintain polarity and the equipment grounding connection.

 

410.153 defines any lighting track rated at over 20 amperes as heavy-duty lighting track. It also requires an individual over current protective device for each fixture attached to heavy-duty lighting track.

 

410.154 states that each four foot section or less of lighting track must have at least two supports if it is installed as a single track. Each 4-foot section added to the system after that must have at least one additional support. This section also requires that the fastening system used must be able to support the maximum weight of the fixtures that can be installed.

 

Summary

 

We hope this part of the module has helped you understand some of the requirements for the installation of fixtures. We recommend you always check the NEC and local ordinances and requirements before installing fixtures.

 

One last thought. Always be aware when installing or working on fixtures. Keep this in mind…..

 

IT IS HOT UNITL YOU PROVE IT IS NOT.