I'm putting in a 4-way switch and I want to use MC cable but I need to get a neutral to one of the 3-ways. Is it code compliant to run the MC cable and just cap off the black conductor at each end?
I'm putting in a 4-way switch and I want to use MC cable but I need to get a neutral to one of the 3-ways. Is it code compliant to run the MC cable and just cap off the black conductor at each end?
I'm just going to use MC 12-2-2. Black, Red, white , green. I didn't think my supply house had it in stock but they do. Thanks for replies.
Gus
I'm just going to use MC 12-2-2. Black, Red, white , green. I didn't think my supply house had it in stock but they do. Thanks for replies.
Gus
Assuming that you are using 12/2 and 12/3 MC cables:. . . a neutral at the first 3-way for the neutral for the lights. The last 3-way will have the power coming in and the neutral which I need to get to first 3-way for the lights.
But if the neutral in a section of two wire (plus ground) MC is used only to carry the return current from an occupancy detector, the inductive heating and other effects will be trivial. Still a code violation though.Should you need a "hot" as well as the neutral at the end switch for some reason, then you will need extra conductor in the cable otherwise standard black, red, white, green will work if you hit one end with power and go to the load off the other end of the switching circuit.
Not only is it a code violation to run just a single conductor in a raceway or cable as earlier suggested, it creates bigger issues if it is steel raceway or jacket on the cable, as you will have inductive heating effects on that steel because there is no conductor carrying opposing current to cancel magnetic effects.
But if the neutral in a section of two wire (plus ground) MC is used only to carry the return current from an occupancy detector, the inductive heating and other effects will be trivial. Still a code violation though.
Still a code violation though.
I'm putting in a 4-way switch and I want to use MC cable but I need to get a neutral to one of the 3-ways. Is it code compliant to run the MC cable and just cap off the black conductor at each end?
If you're using aluminum MC Lite it might actually still be compliant.
300.3(B)(3) says "nonmetallic or other nonmagnetic sheath".
That one is a little trickier. If the initial install was supposed to comply with 2011, then it really was wrong from the start. But the second contractor adding the motion sensor that requires a neutral conductor still was wrong to install it if there is no neutral to connect it to or at least needs to install a proper neutral first, IMO.What if somebody wired 4 way switch with 12/3 and then realized he needs neutral to satisfy that new 2011 code but he is not using the neutral so he does not violate 300.3 (B).
Than next contractor tries to install motion sensor with neutral and he is at violation of 300.3 b.
Would this scenario cover the first contractor?