14 ga. wire on 20 amp circuit

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Hendrix

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I saw it but I don't believe it. EC thinks that he can feed a switch with #12 ga. and go to his fixtures with #14 ga. wire. Please direct me to the article that prohibits this.:-?
 
Hendrix said:
I saw it but I don't believe it. EC thinks that he can feed a switch with #12 ga. and go to his fixtures with #14 ga. wire. Please direct me to the article that prohibits this.:-?
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There isn't one, specifically speaking. The #14 he wants to use would still be branch-circuit conductors. That it supplies a single load, and even a known one, does not matter. They are not 'tap' or fixture' wires.

Granted, for that known load, 15a switches and other devices are permissible, but not the conductors.
 
If, by chance, the circuit's overcurrent protection device is a 20 amp breaker, then 240.4(D) would prohibit what you are describing. If the OCPD is a 15 amp breaker, then what you are describing is acceptable, as Larry has already said.
 
He can do this IFthe circuit is on a 15 amp breaker, I am guessing it is not, so there is no exception that would allow him to put the "switch leg" in a smaller size then the rest of the circuit.
 
The thread title specifies a 20a ckt, which I took to include the OCPD and not just the #12 portion of the circuit.


Hendrix, ask him if a switch at the panel would allow the rest of the circuit to be #14.
 
charlie b said:
If, by chance, the circuit's overcurrent protection device is a 20 amp breaker, then 240.4(D) would prohibit what you are describing. If the OCPD is a 15 amp breaker, then what you are describing is acceptable, as Larry has already said.
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The OCPD is a 20 amp breaker to a switch box, then to a heat, vent , light in 14 ga. wire. The unit draws 14.6 amps when everything is running.
 
Hendrix said:
The OCPD is a 20 amp breaker to a switch box, then to a heat, vent , light in 14 ga. wire. The unit draws 14.6 amps when everything is running.
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The overcurrent device must protect the branch circuit conductors in accordance with 240.4.

In this situation #14 AWG must be protected by an overcurrent device that does not exceed 15 amps. (240.4(D))

Chris
 
There are a few places that do allow #14 on a 15a breaker, and are listed in 240.4(E) and 240.4(G). However, your installation does not meet those criteria, so either the switch loops must be AWG12, or installed on a 15a breaker.

My guess is, the fan/heat/light unit may well require a dedicated circuit in the instructions.

OP is correct, the EC is mistaken.
yes.gif
 
Hendrix said:
I saw it but I don't believe it. EC thinks that he can feed a switch with #12 ga. and go to his fixtures with #14 ga. wire. Please direct me to the article that prohibits this.:-?
Click to expand...


Funny thing is he can probably use a switch rated for 15 amps but must use #12 to the light.
 
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