12-2-2, Three Switch legs

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What about 200.7(C)(1) for re-identifying the 12-2-2 this section also permits a two wire cable to be used for a 240 volt circuit when the white is re-identified.

200.7 Use of Insulation of a White or Gray Color or with
Three Continuous White or Gray Stripes.
(A) General. The following shall be used only for the groun‐
ded circuit conductor, unless otherwise permitted in 200.7(B)
and (C):
(C) Circuits of 50 Volts or More. The use of insulation that is
white or gray or that has three continuous white or gray stripes
for other than a grounded conductor for circuits of 50 volts or
more shall be permitted only as in (1) and (2).
(1) If part of a cable assembly that has the insulation perma‐
nently reidentified to indicate its use as an ungrounded
conductor by marking tape, painting, or other effective
means at its termination and at each location where the
conductor is visible and accessible. Identification shall
encircle the insulation and shall be a color other than
white, gray, or green. If used for single-pole, 3-way or
4-way switch loops, the reidentified conductor with white
or gray insulation or three continuous white or gray
stripes shall be used only for the supply to the switch, but
not as a return conductor from the switch to the outlet.
Click to expand...
 
infinity said:
What about 200.7(C)(1) for re-identifying the 12-2-2 this section also permits a two wire cable to be used for a 240 volt circuit when the white is re-identified.
Click to expand...

Yes. 200.7(C)(1) first sentence is the more general rule, and it is in play for the OP 12-2-2 "Switch Leg" question, while the last sentence is the "switch loop" sub-rule for a very specific assembly (cable switch loops).
 
I read it as the rule applies to "switch loops". It was explained to me that they didn't want more than one conductor that looks like a grounded conductor at a light/load. But that doesn't really make sense if they allow the grounded conductor to be re-identified as an ungrounded conductor in other instances. It also doesn't make sense because you have to re-identify it at both ends anyway. The whole rule needs to go away or be severely re-written.
 
wwhitney said:
Sorry, I meant to say I was responding to your post #6, which is about switch loops.
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No worries. As a point of clarity, my original scenario, with respect to the exhaust fan, was Post #2, as I was responding to the OP "switch legs" question.

When you introduced "Switch Loops" in your post #5, I then responded with the basic idea of the exhaust fan modified so there was your switch loop, in my post #6.

So, your opening line in post #11 seemed to me to say you missed my #2.

For what its worth, I still think the NEC is silent about a second identified conductor in the same cable with the first re-identified conductor correctly supplying a switch.
 
200.7(C)(1) is clear: you can reidentify any white wire in a cable, unless the cable is part of a switch loop and the white conductor is the return from the switch to the outlet.

But, of course, switch loop is not defined. I think for a two-wire load we can say that a switch loop is a single cable with two conductors A and B for which the connectivity is A - switch - B - load. In which case B can not be a reidentified white wire.

For a two-pole thermostat controlling a 240V heater, I don't think a thermostat is a "single-pole, 3-way or 4-way switch" so I'm don't think that the 200.7(C)(1) prohibition applies. But if it did, and if you created two switch loops by bringing 240V power to a heater junction box, and then used a 12-2-2 from the heater to the thermostat, the two white wires would have to be the supplies to the thermostat, and the black and red would have to be the returns from the thermostat to the heater.

Cheers, Wayne
 
LarryFine said:
Then I don't understand your comment. I believe coloring a second white is still stated as okay, because the first white the code addresses is being used correctly.
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Ah. My comment in my post #26 is directed to Wayne W. and is referencing my comment in my post #6 where I suggest that the second white wire in a 12-2-2 cable, when used in a Switch Loop, is (after the first white wire is correctly hooked up as supply to the switch) something that the "switch loop" rule is silent about. That leaves the second white wire, when re-identified, under the rule of the first and second sentence of 200.7(C)(1).

Saying my point another way, the last sentence of 200.7(C)(1), the switch loop rule, requires a cable re-identified white wire to supply the switch, not return from the switch to the outlet. Only one white wire is being talked about in the rule. And that one white wire must be energized and go to the switch, not from the switch to the outlet.

200.7(C)(1) Last Sentence:
If used for single-pole, 3-way or 4-way switch loops, the reidentified conductor with white or gray insulation or three continuous white or gray stripes shall be used only for the supply to the switch, but not as a return conductor from the switch to the outlet. ​
Click to expand...
Note that, after the initial "switch loops" plural, every thing else in the sentence is singular. So, after the re-identified switch loop white wire is correctly connected as supply to the switch, and is not a return to the outlet, the "switch loop" rule is satisfied. Any remaining white wire default to the first two sentences of 200.7(C)(1).

Also, remember that the original language of this rule predates color re-identification by many Code cycles. Back then the switch loop supply to the switch was left white (no recoloring).
 
al hildenbrand said:
Note that, after the initial "switch loops" plural, every thing else in the sentence is singular. So, after the re-identified switch loop white wire is correctly connected as supply to the switch, and is not a return to the outlet, the "switch loop" rule is satisfied. Any remaining white wire default to the first two sentences of 200.7(C)(1).
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Disagree. The requirement applies to reidentifying any white wire that is part of a switch loop. Just because you've successfully complied with the limitation on one white wire in a cable doesn't mean the limitation doesn't apply to other white wires in the cable.

Cheers, Wayne
 
al hildenbrand said:
Yes. 200.7(C)(1) first sentence is the more general rule, and it is in play for the OP 12-2-2 "Switch Leg" question, while the last sentence is the "switch loop" sub-rule for a very specific assembly (cable switch loops).
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Yes, two distinct and different requirements. For the purpose of the 12-2-2 and three switch legs (again feed is already at the switch) I see the first part or 200.7(C)(1) being applicable and since there is no switch loop the second part is not applicable.
 
I'm a tad confused betwixt 'switch loop' & 'switch leg' , neither of which exist in art 100.

so we fall back on art 200 to define it, which this may be key>>


shall be used only for the supply to the switch, but
not as a return conductor from the switch to the outlet.
Click to expand...

in other words, one would find said white and black made together

which is rather 'identifying' to most sparks

perhaps this was the intent:?

~RJ~
 
Re-identifying the white wire as an ungrounded conductor has always been pretty cheesy to me.

JAP>
 
For at least 60 years we used the white conductor as the hot leg to feed the switch with a 2-wire cable. Every electrician in the world knew this. The move to dumb down the NEC to the homeowner level made this re-identification a necessity. IMO it was always just fine the way it was. :roll:
 
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