What do you do with an unused wire in 14-3 cable? Examples would be running a switch loop where you don't need the white wire, or a receptacle where you don't need the extra hot wire. Do you cut the unused wire off where the sheathing ends? If not, are you supposed to identify it in some way to show that it is not being used?

Cap off both ends, may need in the future.

Thanks for your answer. I value your expertise. I'm wondering, though, if I did cut the unused wire where the sheathing ends would that be a violation of the NEC?

Also, after I posted my question I did an internet search and came across something that said that any unused conductor shall be connected to ground, as though it was quoting the NEC.

So I'm wondering what the NEC allows, what it doesn't allow, and what is the most common practice.

This :


Also, after I posted my question I did an internet search and came across something that said that any unused conductor shall be connected to ground, as though it was quoting the NEC.

Is not mentioned in the NEC, as far as I know.

A spare wire simply should be capped at both ends. Cutting off is not a problem, either, but why, when iyt may be helpful in the future.

Thanks, Strat & tk! Capping does make the most sense. It just looks a little odd to me, as though somebody screwed up. But I guess that's the standard practice.

I don't look at it as screwing up, but preparing for options. Some install a light in center of room, instead of light/fan combination, the extra wire allows both. Cap 1 if using only a light.
If it was a switch loop, the extra wire allows a switch/recpticle combo, or a receptacle from that box.
A problem with cutting flush with sheathing, is it leaves a sharp point and could puncture other conductors.

Thanks, Strat & tk! Capping does make the most sense. It just looks a little odd to me, as though somebody screwed up. But I guess that's the standard practice.What looks like someone screwed up is running a 3-wire for a switch loop. That is of course unless you wanted the extra wire for future use.

Years from now someone may need a neutral in a switch loop box and see that capped off wire and be glad it is there.

What looks REALLY screwed up is a wire cut off flush in the box. That helps no one.

Exactly,


What looks REALLY screwed up is a wire cut off flush in the box. That helps no one.

The looks of sloppy workmanship, or hiding an oops.

Spare wires come in handy when you never expect.

Cutting is a waste of copper.

Site of pink copper inside a box scares the be-jesus out of troubleshooters.

Box fill would be the only reason, still know of no Electrician who would cut this off.