Run that by me one more time

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neutral

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:confused: What's the problem with using 14 ga. wire for a switch leg for lighting on a 20 amp circuit? What NEC Article should I read that would give me the answer? I have the 2005 Book and the 2008 code on CD. Could anyone involved in putting together the codes be smarter than a 5th Grader?
 
The problem is that #14 AWG wire is rated to handle 15 amps, so putting a 14 AWG wire on a 20 amp overcurrent device could lead to a potential failure of the wire due to an overcurrent. Take a look at 240.4(D) for the general code requirement for #14 AWG wire to be protected at 15 amps.

Chris
 
So if I have a 2 tube 4 ft Florescent fixture with a 6 ft 18 ga. flexible cord attached I can't plug it into a 20 amp Receptacle
 
In my opinion the switch leg is an extension of the fixture wire. I haven?t seen any fixture with a 50 foot or 100 foot wire attached
 
neutral said:
In my opinion the switch leg is an extension of the fixture wire. I haven?t seen any fixture with a 50 foot or 100 foot wire attached
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Your switch loop is part of the branch circuit, not fixture wire. Read the definition of a branch circuit (Art. 100).
 
neutral said:
In my opinion the switch leg is an extension of the fixture wire. I haven?t seen any fixture with a 50 foot or 100 foot wire attached
Click to expand...

The J-box where you connect you fixture to the building wiring is a lighting outlet. The conductors between the switch and the lighting outlet where you connect you fixture is part of the branch circuit, not an extention of the fixture wire.

A fixture whip that is attached to a light fixture and contains conductors that you connect to a lighting outlet would be an example of fixture wires.

Chris
 
Have you ever seen a problem caused by using a 14 ga. switch leg on a light fixture?
I have been in the trade since 1960 and never seen one problem related to using 14ga wire for a switch leg. and I have seen a lot of problems. even a few I created (ok a lot) :smile:

Charlie
 
(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

I like # 3
 
neutral said:
(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

I like # 3
Click to expand...
Thats all well and good, but what is your wiring method? NM, MC mabey conduit and THHN?

I don't see those listed in T402.3.
 
neutral said:
Have you ever seen a problem caused by using a 14 ga. switch leg on a light fixture?
I have been in the trade since 1960 and never seen one problem related to using 14ga wire for a switch leg. and I have seen a lot of problems. even a few I created (ok a lot) :smile:

Charlie
Click to expand...

No offense, but "So?"

I haven't seen many problems because there aren't too many out there wired that way to begin with.
 
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neutral said:
(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

I like # 3
Click to expand...

#3 works well for fixture wire, which a switch leg is not.;)

Chris
 
wasasparky said:
It's actually rated to handle 20A. The code, not the conductor properties, limit its use.:cool:
Click to expand...

On that note terminations are the key word of the day 110.14. which is dealing with premise wiring and the OP is mentioning fixture wiring.
 
neutral said:
I have been in the trade since 1960 and never seen one problem related to using 14ga wire for a switch leg.
Click to expand...


What kind of industrial electrician uses #14 ga. wire anyway? I have done lots of industrial work and never saw #14 used for anything other than controls and fire alarms. Many contractors don't even have any #14 on the job or at the shop. So where did the idea of useing #14 for a switch leg even come from to start with?

Other than the fact that it's illegal it would probably cost more to switch wire type to a smaller gauge just for switch legs than it would save in wire cost.
 
wasasparky said:
It's actually rated to handle 20A. The code, not the conductor properties, limit its use.:cool:
Click to expand...

You are correct, I should have stated that section 240.4(D) limits the overcurrent protective device for gereral circuits utilizing #14 AWG to 15 amps. :rolleyes:

Chris
 
neutral said:
In my opinion the switch leg is an extension of the fixture wire.
Click to expand...
Shake that opinion and you'll understand. Fixture wires begin at the lighting outlet and end at the fixture. They are never run as in-wall circuit conductors.
 
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