residential deadend threeway

[Pharon]

You also don't need a neutral for a three or four way switch loop, per the 404.2(A) exception.

 

[kwired]

You also don't need a neutral for a three or four way switch loop, per the 404.2(A) exception.

I have to argue that if the CMP wanted that exception to apply to 404.2(C) (which is for switches controlling lighting loads and where the grounded conductor requirement is) that they should have put the exception there as well or somehow arranged things so the exception clearly covers both sections. Otherwise as written I see 404.2(A) being a general requirement for three and four way switches, and 404.2(C) being information that specifically covers switches controlling lighting loads and it does require a grounded conductor at switch locations, or a way to add one if ever needed.

 

[Pharon]

So you're saying you think the 402.4(A) exception only applies to non-lighting three and four way switches? Like switched receptacles?

Because the way I read it is that as long as it's a switch loop, it doesn't matter what the load is, and the exception applies.

But in order to qualify as a switch loop, the line power needs to come directly into the outlet before going out to the switches. If line power comes into one of the switches, then it's not a switch loop.

But maybe I'm interpreting that all wrong.

 

[kwired]

So you're saying you think the 402.4(A) exception only applies to non-lighting three and four way switches? Like switched receptacles?

Because the way I read it is that as long as it's a switch loop, it doesn't matter what the load is, and the exception applies.

But in order to qualify as a switch loop, the line power needs to come directly into the outlet before going out to the switches. If line power comes into one of the switches, then it's not a switch loop.

But maybe I'm interpreting that all wrong.

If line power comes into one of switches first - you have the grounded conductor at the switch anyway.

What I see is part A giving us a general requirement, and part C giving us additional requirements for a specific instances. They did not do a very good job of clarifying whether or not the grounded conductor is necessary in a situation where both are combined.

I looked at 2011 NEC and see that the exception to (A) was not highlighted as a change from 2008 - so it's existence was prior to adding (C), which makes it harder to determine intentions as well, had it been changed in 2011 maybe would mean they intended to not need any grounded conductors for three way circuits controlling lighting loads, but something tells me that exception has nothing to do with the requirements of (C)


Add: if you want to use exception to (A) for a circuit supplying lighting loads, you better convince your AHJ it applies there, is the best advice I can give on this.