Switching through neutral

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1

I want to replace one switch in a 3-switch 3gang with a GE/Jasco enbrighten switch. The builder switched these 3 through the neutral not the hot. Do I need to rewrite the whole box to switch through the hot or can I switch through the neutral with these z-wave switches?

(I've already installed 4 of them in other rooms switched through the hot and they work fine)

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How did it pass inspection? Anyway, you’ll have to rewire.

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Are you positive the neutral is switched? Or is the neutral wire being used as a traveler?

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Are you sure it’s switching the neutral or are you going off wire color? Wire colors aren’t governed by code. White wire hooked up to a switch is often hot.

Edit: if you open the box and take a clear pictures of the wiring in the back of the box and to the switch I am happy to provide some guidance.

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5

Although, in my experience, it is a relatively common practice to mark a white as being hot by coloring the end black with a little piece of electrical tape or a sharpie.

@zipper - do you have a multimeter? What is the voltage between the conductors? If it is a neutral, there should be ~0 VAC (very close to zero) between neutral and ground.

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My house is almost totally wired with switch loops. The hot goes to the fixture first, not the switch. The incoming hot wire in the box with the switch (in my house) is always the white wire (unmarked in any way). Out going switched hot is the black wire. So don’t count on the white being the neutral wire. I doubt that you have a switched neutral but you won’t know until you check it out with a meter if you have one and are comfortable doing it.

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7

Thanks for the replies! No I'm not sure it's neutral, was just going off the color. I have a multimeter, though I've never used one on mains AC power. There was another box near by with the colors totally reversed. I'll have to read a bit on checking bc I've never done that before with a meter.

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  1. Be careful. Remember AC can kill.
  2. This video might help - https://youtu.be/qyAPIui38HE
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Multimeters are great, but a non contact voltage checker is indispensable for working with line voltage AC...

Hold it next to the wire. If it beeps, the wire is live. Best safety tool you can have for working with your own electrical.

https://www.amazon.com/Southwire-Tools-40116N-Detector-100-600V/dp/B01M24N714/

In any case, one side of the switch will always be hot if the switch is off, regardless of whether or not the switch is before or after the load. The other side will not be, and will be at zero volts. As others have mentioned, you'll probably need to open everything up and find out how the whole circuit is wired. First test would be to see if you have voltage in the light fixture with the switch in the OFF position. Using a non-contact tester and taking all necessary safety precautions, of course. My process is

  • turn off the breaker. For multi-gang boxes, de-energize ALL circuits in the box.
  • try turning the lights on... if they turn on, go back to step one.
  • [carefully] disassemble the box only as far as is necessary to verify all wires are de-energized. If the tester beeps, go back to step one.
  • take a picture before disconnecting any wires.
  • continue disassembly as needed. Test again because, why not?
  • re-energize the circuit and test for voltage as needed. Take appropriate care to make sure wires are separated and capped BEFORE turning the breaker back on.
  • de-energize, test for voltage, and reassemble. Use the picture to double check your work.
  • re-energize and test for proper operation.

And finally, share pictures and findings with community so we can help find a solution!

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Thanks for the help all! You folks were right, it was switched through hot, but the hot was white on one side of the switch and black on the other. I think my house is wired with switch loops as well!

In an unrelated note, I figured out you can stick the wires into the little holes on the bottom of these switches instead of wrapping around the screw. That would've saved me sooo much time on the first set of these.

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Thanks! I just ordered one of these. Will definitely help my safety and it looks soo much easier to use than a multimeter.

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That is called back stabbing and is actually a bad idea as discussed many times on this forum and on youtube. Wrapping the screw would be a shepherds hook (possibly has another name). The newest, best and easiest way is a "backwire", similar to a backstab but the screws are setup to accept a straight wire from the back and it is clamped down with the screw and a washer of sorts.

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I've heard all the arguments against backstabbing, but it's allowed by code and the NEC's sole purpose is to prevent electrical fires and death. So how bad can it really be?

I personally use the screws on my own work, but my whole house is wired with back stabs. I don't lose any sleep over it.

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I haven't seen any new smart switches (z-wave or zigbee) that permit back stabbing. Have you? If my perception is correct then @zipper is also probably referring to back wiring his smart switches.

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No, good point, I thought maybe he was talking about old dumb 3-way switches. I think you are right though he is talking about smart switches so they are probably fine the way he did it. When I added my smart switches I took all the gross ivory 3-ways out which were back stabbed and replaced with new white decora switches all back-wired proper now with screw-less cover plates.

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