Can 14 AWG copper conductors be used to supply a light fixture on a 20 amp circuit?

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david luchini

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While (a) covers the wires running from the outlet to the luminaire )

I don't think this makes sense...210.19(A)(4) Ex 1 deals with branch circuit taps.

The branch circuit is all conductors from the final overcurrent protective device protect the circuit and the outlet(s). Beyond the "outlet" is no longer "branch circuit."
 

GoldDigger

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I don't think this makes sense...210.19(A)(4) Ex 1 deals with branch circuit taps.

The branch circuit is all conductors from the final overcurrent protective device protect the circuit and the outlet(s). Beyond the "outlet" is no longer "branch circuit."
There are several areas where the building wiring system terminates at an "outlet" box in a wall but the NEC still concerns itself with the hard wiring from that outlet to the device that is being powered.
Or else you fall back on the interpretation that the only "outlet" for a hard wired garbage disposal is located at the junction box on the disposal itself.
Lots of room for interpretation there.

Getting back to your original point, can you explain to me just why (a) would be concerned about running an unlimited length branch tap and then going 18" past the boundary of the luminaire? No mention is made of the location of any "outlet" in this exception.
 
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MasterTheNEC

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I don't think this makes sense...210.19(A)(4) Ex 1 deals with branch circuit taps.

The branch circuit is all conductors from the final overcurrent protective device protect the circuit and the outlet(s). Beyond the "outlet" is no longer "branch circuit."

The Branch Circuit is extending to the outlet box, which in the example has the switch device. In order for you to make the "TAP" rules apply in your favor you are choosing to call that entire circuit from the switch to the lighting outlet a "TAP"...in my opinion by doing so you limit it to only being 18" in length. The basic rule of the NEC is to protect a conductor in accordance with it's ampacity. However, you are saying that it is permitted to fun a 14 AWG at no defined length and protect it with a 20 A OCPD. That's what I am reading into it...sorry but I just say what I see.

In my view you are "tapping" a branch circuit if you are attempting to use the "TAP" allowances from the switch to the outlet in question. I don't see where (A) or (C) complies.
 

david luchini

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There are several areas where the building wiring system terminates at an "outlet" box in a wall but the NEC still concerns itself with the hard wiring from that outlet to the device that is being powered.

Ex 1(c) doesn't say anything about an "outlet box." I don't think anything in the NEC says that the "outlet" must be at a "box." The "outlet box" that you describe here is NOT the "outlet" at all as far as the code is concerned, if the premises wiring system continues on past that box.

Getting back to your original point, can you explain to me just why (a) would be concerned about running an unlimited length branch tap and then going 18" past the boundary of the luminaire?

I have no idea why the Code is written the way it is. As I said earlier, I suspect they allow you to extend beyond the individual luminaire to connect to a control device for that individual luminaire.

No mention is made of the location of any "outlet" in this exception.

Nor is there any mention mad of any "outlet" at Exs 1(b), 1(d) or 1(e), but they all connect to the premises wiring system via an "outlet."
 

MasterTheNEC

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Just being a devils advocate....Your argument should be to NOT use any of the exception and use the general statement in 210.19(A)(4) and say the load is considered and the conductors are not smaller than 14 AWG and...hope the inspector agrees.
 

david luchini

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The Branch Circuit is extending to the outlet box, which in the example has the switch device. In order for you to make the "TAP" rules apply in your favor you are choosing to call that entire circuit from the switch to the lighting outlet a "TAP"...in my opinion by doing so you limit it to only being 18" in length.

A switch box is not an "outlet."

Yes, the entire circuit from the switch to the lighting outlet is a "tap." I don't see any tap length limit in Ex 1(a). There is a tap length limit in Ex 1(b) and Ex 1(c). But again, there is no length limit in Ex 1(d) or Ex 1(e).

The basic rule of the NEC is to protect a conductor in accordance with it's ampacity. However, you are saying that it is permitted to fun a 14 AWG at no defined length and protect it with a 20 A OCPD. That's what I am reading into it...sorry but I just say what I see.

In my view you are "tapping" a branch circuit if you are attempting to use the "TAP" allowances from the switch to the outlet in question. I don't see where (A) or (C) complies.

Yes, the basic rule is to protect the conductor in accordance with its ampacity...but these are EXCEPTIONS to those rules.
Tap conductors shall have an ampacity sufficient for the load to be served. In addition, they shall have an ampacity of not less than 15 for circuits rated less than 40 amperes...

The whole point of the tap rule exceptions are to permit conductors to be protected at higher than their ampacity.
 

MasterTheNEC

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A switch box is not an "outlet."

Yes, the entire circuit from the switch to the lighting outlet is a "tap." I don't see any tap length limit in Ex 1(a). There is a tap length limit in Ex 1(b) and Ex 1(c). But again, there is no length limit in Ex 1(d) or Ex 1(e).



Yes, the basic rule is to protect the conductor in accordance with its ampacity...but these are EXCEPTIONS to those rules.

The whole point of the tap rule exceptions are to permit conductors to be protected at higher than their ampacity.

Ok...I can see this is futile so we can agree to disagree, I agree the device box in question is not an outlet per the NEC but you know what I meant. I wish the OP good luck on his inspection;)
 

GoldDigger

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Yes, the entire circuit from the switch to the lighting outlet is a "tap." I don't see any tap length limit in Ex 1(a).
And there is where we differ.
For (a) I see the limitation in length for the entire tap to be 18" plus whatever may be inside the footprint of the luminaire.
Not 18" plus however long the portion of the tap conductor in the wall may be.
That seems transparently clear to me, so it will definitely be argued for a long time with no resolution. :)
I wonder whether the Handbook and/or the ROP going back to the adoption of that section may be of interest?
The Handbook does not help and I am not planning to do the ROP research any time soon.
 
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