20 amp circuit, #14 Switch Leg

[augie47]

Was a #14 "switch leg" ever Code allowable on a 20 amp circuit ??
It was commonplace in this area eons ago (although I don't think Code compliant) and I have someone questioning the practice on a house constructed in the mid 90s.

 

[DTLight]

I'm not sure if it was so much allowed, as it wasn't disallowed. In my house, built around 2000, all the branch circuits are 20A with #12 from the panel to the first device or splice and #14 from there on.

 

[infinity]

240.4(D) was in earlier editions at the bottom of table 310-16. Those limitations appear in the 1981 NEC and possibly even earlier editions.

 

[Dennis Alwon]

I don't think it ever was code compliant however was done everywhere

 

[480sparky]

The "Small Conductor Rule" dates to 1959. However, switch legs & loops have never been an exception.

 

[jxofaltrds]

From 1999 NEC 240-3(d)



Now how much of that is new I do not know.

 

[GoldDigger]

I'm not sure if it was so much allowed, as it wasn't disallowed. In my house, built around 2000, all the branch circuits are 20A with #12 from the panel to the first device or splice and #14 from there on.

Kind of makes you think it was done to deceive the inspector, since there is no logical reason why the risks are any less downstream of the first device, especially if the device is a receptacle.

 

[LEO2854]

Kind of makes you think it was done to deceive the inspector, since there is no logical reason why the risks are any less downstream of the first device, especially if the device is a receptacle.

It would be much easier back when Romex was all white outer jacket regardless of the size,maybe that's why they color coded it..

 

[Volta]

The "Small Conductor Rule" dates to 1959. However, switch legs & loops have never been an exception.

And heck, Subsection 23d. was limiting taps from a No. 12 B. & S. gage (sic) to an 18" maximum over 90 years ago.

 

[templdl]

Was a #14 "switch leg" ever Code allowable on a 20 amp circuit ??
It was commonplace in this area eons ago (although I don't think Code compliant) and I have someone questioning the practice on a house constructed in the mid 90s.

Is the #14 switch leg protected with a 20a breaker? Personally it don't think it is. How can it be assured that the #14 wire be protected when it is rated for 15a when it's being feed with a 20at breaker?
It isn't even code as I recall to pigtail from a 20a circuit wired with #12 to a 15a duplex using #14 wire.
'

 

[ActionDave]

I think we should be allowed to do this now. It would save a lot of copper that could be used by future generations.

 

[augie47]

Is the #14 switch leg protected with a 20a breaker? Personally it don't think it is. How can it be assured that the #14 wire be protected when it is rated for 15a when it's being feed with a 20at breaker?
It isn't even code as I recall to pigtail from a 20a circuit wired with #12 to a 15a duplex using #14 wire.
'

I don't disagree and when I 1st started inspecting was surprised to see it as a common practice in this area, and as Dennis notes, others as well. Even today I will find ir done on occasion and it's usually by an ole timer who has always done it that way. My research could not find where it was Code permissible but because of the common practice in the 90s I was asking.
(Withing the last few months I have had out-of-town guys install using that method and both were experienced north Georgia electricians who advised it was "standard practice at home".)

 

[kwired]

Is the #14 switch leg protected with a 20a breaker? Personally it don't think it is. How can it be assured that the #14 wire be protected when it is rated for 15a when it's being feed with a 20at breaker?
It isn't even code as I recall to pigtail from a 20a circuit wired with #12 to a 15a duplex using #14 wire.
'

But a 15 amp duplex is still rated for 20 amp to the complete device and/or for feed thru. There may be more validity to tapping a 14 AWG and landing it on a single 15 amp receptacle.

I don't disagree and when I 1st started inspecting was surprised to see it as a common practice in this area, and as Dennis notes, others as well. Even today I will find ir done on occasion and it's usually by an ole timer who has always done it that way. My research could not find where it was Code permissible but because of the common practice in the 90s I was asking.
(Withing the last few months I have had out-of-town guys install using that method and both were experienced north Georgia electricians who advised it was "standard practice at home".)

Maybe they have inspectors in the area that don't know any better, or possibly local amendments that allow this practice, though I find that somewhat unlikely.

 

[roger]

This is one of those situations that is not a hazard in most residential applications even though it is a violation of the NEC. Typically in a dwelling the switch leg will only carry a small current feeding a couple of fixtures or less but, I could see some major confussion if an exception to the rule was to be added.

Roger

 

[kingpb]

Since the switch is only rated for 15A, then why not allow the switch leg to be #14AWG.

Maybe the NEC should require receptacles to be 20A and lighting circuits to be 15A, and you can't mix them.

But wait, that is design and not related to safety, and we all know the NEC should not be used as a design guide.:rotflmao:

 

[roger]

Since the switch is only rated for 15A, then why not allow the switch leg to be #14AWG.

Maybe the NEC should require receptacles to be 20A and lighting circuits to be 15A, and you can't mix them.

But wait, that is design and not related to safety, and we all know the NEC should not be used as a design guide.

You do realize they make 20 amp switches don't you? In many non dwelling installations a lighting circuit can be heavily loaded and we very seldom use any 15 amp switches

Roger

 

[Dennis Alwon]

I think the problem here is overload not short circuit or ground fault. In most cases the 14 gauge wire will certainly trip a 20 amp overcurrent protective device when a GF or short circuit occurs. I really don't see it as likely but lights could be added to the point that the 14 gauge switch leg is pulling more than 15 amps but not enough to trip the 20 amp overcurrent protective device. Unlikely yes but I think the code needs to stay as written

 

[480sparky]

And heck, Subsection 23d. was limiting taps from a No. 12 B. & S. gage (sic) to an 18" maximum over 90 years ago.

Tap rules are not the same as the Small Conductor Rule.

 

[GoldDigger]

Tap rules are not the same as the Small Conductor Rule.

No, but changing wire size downward without going through an overcurrent device can create a tap, whether you use small conductors or not.

 

[Volta]

Tap rules are not the same as the Small Conductor Rule.

Yup, you sure are right. Different sections. :roll: But it sure does show just how long we have been generally prevented from connecting lengths of #14 to standard 20 amp circuits.