Florescent Light Fixture Disconnect

[jusme123]

Scenario; 1- 2'x4' fluorescent fixture with 2 ballast inside, each ballast has its own disconnect (orange plug disconnects). The fixture is a row fixture with 6#10 (2 Hot ,2 Neutral ,2 Ground) .

Now, here is the question, is it code to take #18 AWG wire (instead of #12 AWG) and connect it to the line side of each ballast disconnect within the fixture to make it easier to connect the 2 # 10 AWG wires that feed fixture ?

I said its a violation because the line side of disconnect has to be a #12 AWG since it is protected by 20A breaker and the minimum wire size is #12 AWG. What say you?

 

[Sierrasparky]

Is this a 20 amp circuit? or 30

I would think you could use a fixture wire.

 

[jusme123]

Is this a 20 amp circuit? or 30

I would think you could use a fixture wire.

...its a 20 amp circuit. I do realize the place would not burn down by using the fixture wire within the fixture, but I'm looking for a code reference because the line side is protected by a 20A circuit breaker and the min wire size is #12. I know its a technicality, but when engineers are involved ............

 

[ActionDave]

Code does not say, but...

1. If you get rid of the orange thingy in the middle you have 12AWG wires connected to 18 gauge ballast wires. I'm not seeing a problem.

2. Fluorescent fixtures come from the factory wired with 18 gauge coming out of both ends of the orange thingy so manufactures don't have a problem.

3. Code says lights have to be listed. Listed lights leave the factory with little wires coming out of both ends of their orange thingys. Code gives this arrangement it's blessing.

I would say code does not have a problem, but the reality is if you look too hard at the code or ask too much of it there is always a problem.

 

[jimdavis]

I see no code violation with your scenario. It's a fixture tap from the branch circuit conductors to the luminaire disconnect.

 

[iwire]

I said its a violation because the line side of disconnect has to be a #12 AWG since it is protected by 20A breaker and the minimum wire size is #12 AWG. What say you?

I say I do not agree.

 

[qcroanoke]

Code does not say, but...

1. If you get rid of the orange thingy in the middle you have 12AWG wires connected to 18 gauge ballast wires. I'm not seeing a problem.

2. Fluorescent fixtures come from the factory wired with 18 gauge coming out of both ends of the orange thingy so manufactures don't have a problem.

3. Code says lights have to be listed. Listed lights leave the factory with little wires coming out of both ends of their orange thingys. Code gives this arrangement it's blessing.

I would say code does not have a problem, but the reality is if you look too hard at the code or ask too much of it there is always a problem.

I agree with Dave on all 3 points.

 

[fmtjfw]

410.64(C), 410.117(C)

410.64(C), 410.117(C)

410.64 Luminaires as Raceways.
(C) Luminaires Connected Together. Luminaires designed for end-to-end connection to form a continuous assembly, or luminaires connected together by recognized wiring methods, shall be permitted to contain the conductors of a 2-wire branch circuit, or one multiwire branch circuit, supplying the connected luminaires and shall not be required to be listed as a raceway. One additional 2-wire branch circuit separately supplying one or more of the connected luminaires shall also be permitted.

410.117 Wiring.
(C) Tap Conductors. Tap conductors of a type suitable for the temperature encountered shall be permitted to run from the luminaire terminal connection to an outlet box placed at least 300 mm (1 ft) from the luminaire. Such tap conductors shall be in suitable raceway or Type AC or MC cable of at least 450 mm (18 in.) but not more than 1.8 m (6 ft) in length.

The fixture is allowed to be a raceway for circuit(s) powering luminaires. UL listed fixture whips used to feed power to a luminaire can be as small as #18, as long as the ampacity of conductor is sufficient for the load. Using a short piece of fixture wire as you asked is no problem.

 

[jusme123]

Code does not say, but...

1. If you get rid of the orange thingy in the middle you have 12AWG wires connected to 18 gauge ballast wires. I'm not seeing a problem.

2. Fluorescent fixtures come from the factory wired with 18 gauge coming out of both ends of the orange thingy so manufactures don't have a problem.

3. Code says lights have to be listed. Listed lights leave the factory with little wires coming out of both ends of their orange thingys. Code gives this arrangement it's blessing.

I would say code does not have a problem, but the reality is if you look too hard at the code or ask too much of it there is always a problem.

we installed thousands of lights and not one had the factory wires at both ends of the disconnect. Not stating they don't, just my experience

 

[iwire]

Consider the following ..

240.5(B)(2) Fixture Wire. Fixture wire shall be permitted to be
tapped to the branch-circuit conductor of a branch circuit in
accordance with the following:

(1) 20-ampere circuits ? 18 AWG, up to 15 m (50 ft) of
run length

(2) 20-ampere circuits ? 16 AWG, up to 30 m (100 ft) of
run length

(3) 20-ampere circuits ? 14 AWG and larger

(4) 30-ampere circuits ? 14 AWG and larger

(5) 40-ampere circuits ? 12 AWG and larger

(6) 50-ampere circuits ? 12 AWG and larger

Keep in mind THWN/THHN is not fixture wire.

See Table 402.3 for a list of fixture wire types.

 

[jap]

Scenario; 1- 2'x4' fluorescent fixture with 2 ballast inside, each ballast has its own disconnect (orange plug disconnects). The fixture is a row fixture with 6#10 (2 Hot ,2 Neutral ,2 Ground) .

Now, here is the question, is it code to take #18 AWG wire (instead of #12 AWG) and connect it to the line side of each ballast disconnect within the fixture to make it easier to connect the 2 # 10 AWG wires that feed fixture ?

I said its a violation because the line side of disconnect has to be a #12 AWG since it is protected by 20A breaker and the minimum wire size is #12 AWG. What say you?

View attachment 10537

If you asked me this question over the phone,I would say it would be a code violation, since by the way it's worded you've just bypassed the Disconnect.

JAP>

 

[jusme123]

If you asked me this question over the phone,I would say it would be a code violation, since by the way it's worded you've just bypassed the Disconnect.

JAP>

I don't believe its worded incorrectly, all branch circuit conductors (#10's)are pig tailed to the line side of each ballast disconnect .

 

[iwire]

I don't believe its worded incorrectly, all branch circuit conductors (#10's)are pig tailed to the line side of each ballast disconnect .

But the disconnecting means has nothing to do with the tap conductors.

If the disconnect exists or not does not change the tap rules.

 

[fmtjfw]

Consider the following ..



Keep in mind THWN/THHN is not fixture wire.

See Table 402.3 for a list of fixture wire types.

And none of the scrap wire you get when you dress the ballast wiring is THHN/THWN, it is all fixture wire.

 

[xformer]

I think what is being looked for is 410.48.

Excess wiring shall be avoided.

Or we can look at

410.56 (D)
Splices and Taps.
No unnecessary splices or taps shall be made within or on a luminaire.

 

[fmtjfw]

I think what is being looked for is 410.48.

Excess wiring shall be avoided.

Or we can look at

410.56 (D)
Splices and Taps.
No unnecessary splices or taps shall be made within or on a luminaire.

The OPs problem was that the fixture branch circuits are wired with #10 on 20A circuits and ballast disconnects do not allow wire that large. He asked if he could splice a smaller wire to the #10 without violating NEC.

There are several answers on how to reduce the #10:

1) He could used a white and non-white #12 THHN which will work with a ballast disconnect, meets the general requirement for 20A OCPD
2) He could use a white and non-white #18 fixture wire, because smaller wires are allowed in luminaires and it meets the special requirements for such use. [and he can cut the wires off from the existing ballast shortening the power leads without climbing down the ladder.]

Adding a splice to reduce #10 to #12 or smaller is necessary for this application.

 

[squaredan]

Consider the following ..



Keep in mind THWN/THHN is not fixture wire.

See Table 402.3 for a list of fixture wire types.

All the times I have my nose in the code book and I never saw this one(240.5B(2)) , nice..We do alot of ballast change out and installing new fixtures..It seem a little weird that you can tap up to 50ft of 18AWG fixture wire on a 20amp circuit, but you can.

Does T402.5 ampacities good for all the fixture wire insulation temp rating in T402.3?

 

[fmtjfw]

All the times I have my nose in the code book and I never saw this one(240.5B(2)) , nice..We do alot of ballast change out and installing new fixtures..It seem a little weird that you can tap up to 50ft of 18AWG fixture wire on a 20amp circuit, but you can.

Does T402.5 ampacities good for all the fixture wire insulation temp rating in T402.3?

Fixtures, especially ballasts, have a very predictable full-load current, Unlike receptacle circuits that are usually completely unpredictable. This is probably why you can use smaller conductors for feeding fixtures.

No properly functioning ballast is likely to draw more than 200W/100V (for losses using 100 not 120) or about 2A.

The fixture wire will be rated a minimum of 90?C which required for conductors near ballasts. #18 is rated for 6A. You would have to do a lot of derating, down to about 33%, to get to 2A. The temperature derating factor for 90?C wire with an ambient temperature of 85?C is 29%. [T310.15(B)(2)(a)]

 

[iwire]

The fixture wire will be rated a minimum of 90?C which required for conductors near ballasts. #18 is rated for 6A. You would have to do a lot of derating, down to about 33%, to get to 2A. The temperature derating factor for 90?C wire with an ambient temperature of 85?C is 29%. [T310.15(B)(2)(a)]

I don't believe you have to derate fixture conductors.