#14 for switch legs?

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To the best of my knowledge, it was never allowed by Code, yet it is a practice that was commonplace in this area (TN) and "accepted" by inspectors at one time. Although it has been emphasized for years now that such practice is not Code permissible, I still find it on rare occassion, normally with an older electrician.
 
Somewhere, not long ago, there was a thread on this very subject. Local codes allowed it, even though it didn't jive with the NEC.
 
240.4(D) leases no wiggle room on this at all. I had a young electrician tell me the other day that his "old Master" said he could do this. I informed him that his new Master says he can't because the NEC says he can't!:D
 
iaov said:
240.4(D) leases no wiggle room on this at all.:D
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240.4 (E) Tap Conductors
Tap conductors shall be permitted to be protected against overcurrent in acordance with the following:
(2) 240.5(B)(2) Fixture wire

240.5 (B)(2) Fixture Wire
Fixture wire shall be permitted to be tapped to the branch circuit conductor or a branch circuit in accordance with the following:
(1) 20-ampere circuits - 18 AWG and larger up to 50' of run length
(2) 20-ampere circuits - 16 AWG and larger up to 100' 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'm not saying I do this myself. Just brought this up for discussion. Based on 2005 NEC.
 
active1 said:
240.4 (E) Tap Conductors
Tap conductors shall be permitted to be protected against overcurrent in acordance with the following:
(2) 240.5(B)(2) Fixture wire

240.5 (B)(2) Fixture Wire
Fixture wire shall be permitted to be tapped to the branch circuit conductor or a branch circuit in accordance with the following:
(1) 20-ampere circuits - 18 AWG and larger up to 50' of run length
(2) 20-ampere circuits - 16 AWG and larger up to 100' 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'm not saying I do this myself. Just brought this up for discussion. Based on 2005 NEC.
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Right, well that's why they have 18's in the light fixtures, it's fixture wire. Not NM.
Can fixture wire be run from the switch box, through the wall and ceiling, to a fixture box?

Some call me Doug.
 
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Why is the legnth listed up to 100' in (2) but the legnth unrestricted in (3).
When would you have a fixture wire longer than 100'? That could be a 10 story down rod?
 
Fixture wires are covered in Art 402, and does not include insulation types listed in T310.13(A).
 
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active1 said:
When would you have a fixture wire longer than 100'? That could be a 10 story down rod?
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Well that is a mighty long down rod I must admit. :D

But picture one 3' down rod located at the end of a long row of linear lighting. Ten 8' fixtures is 80', not uncommon in office buildings.

App_Lightedge%20Curved%20Shallow%20Indirect-Open_Open%20Office_13_large.jpg
 
iWire,

What is your take on using #14 as a tap from a #12 circuit,
for the purpose of attaching a Receptical?

I am not asking for a 'ruling', just a comment.

Personally, I think 'diversity' would lean in this direction,
just as justifying a 15Amp Receptical on a 20Amp circuit.

We do use the 'tap' rules on conveyer, motor applications, etc.

But in residential, I still don't downsize the wire or devices.
I get paid to fix too much of this cheap stuff.
 
402.7 Number of Conductors in Conduit or Tubing
The number of fixture wires permited in a single conduit or tubing shall not exceed the percentage fill specified in Table 1. Chapter 9.

402.10 Uses Permitted
Fixture wires shall be permitted
(2) for connecting luminaires (lighting fixtures) to the branch-circuit conductors supplying the luminaires (fixtures).

Table C.4 Is a chart showing the bumber of fixture wires in conduit. It gos up to 2" with hundreds of fixture wires in the raceway. The same for C-8 RMC, C-10 PVC, etc.


I do remember seeing in older construction square can lights wired back to a switch with fixture wire made of maybe 16 ga. I was thinking the thought for the use was the fixture wire had a higher temp rating. The fixture wire insulation was like new, not brittle and cracking. I would also guess it was not done to save money or time as the rest of the home was TW wire.
 
active1 said:
Why is the legnth listed up to 100' in (2) but the legnth unrestricted in (3).
When would you have a fixture wire longer than 100'? That could be a 10 story down rod?
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One reason for the confusion is that these lengths must be used in concert with table 402.5 which limits the ampacity that different size fixture wires can carry. The actual requirement is a combination of 240.5(B)(2) and Table 402.5.

As Bob said it common in rows of fixtures to use fixture wires smaller than the branch circuit conductors. 240.5(B)(2) limits the length of these wires, Table 402.5 limits the ampacity of the load.
 
glene77is said:
Personally, I think 'diversity' would lean in this direction,
just as justifying a 15Amp Receptical on a 20Amp circuit.
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There is a significant difference: the 15a receptacle's rating is based on the slot shape (i.e., it rejects other plug configurations), not its electrical capacity.
 
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