6/3 Cable used as 6/2 - what to do with spare conductor?

[Mark Ashmeade]

I need to run a short length (4 feet) of Romex 6/2 to a 240V 50A receptacle from my sub panel. This is for a 3-phase rotary converter.

Inadvertently, I bought 6/3 cable, not 6/2. My options as I see them:

1. Junk it, learn the lesson and buy some 6/2.
2. Strip the insulation, cut the white conductor at both ends at the insulation, and presto, 6/2 red and black. In a long run, I wouldn't do this, the extra conductor might come in useful, but 4 feet from the sub panel, not so much. I'd rather not have a foot of "loose" 6ga cable in the panel.
3. Cap the ends of the white wire and leave it intact. Still have the problem of a foot of cable inside the box though.

What to do?

[Dan Friedrichs]

"Saving" the white wire for something probably isn't practical because it's such a short piece of cable - I'd just cut it off (your option #2).

Alternatively, parallel it up with one of the other wires. Won't hurt anything, and then you can save it without having it dangling around inside the box.

[Jim Rimmer]

+1 for #2

[Howard Acheson]

I'm not an expert but I don't think you can do #2. I don't believe that the wires inside Romex are insulated or labeled for stand-alone use. Could be wrong.

I think #3 is the best option. Just put a wire cap on each end, coil it up neatly and put it it a corner.

[Thomas Hotchkin]

Mark
Put a cap on both ends. Install a couple of plastic tie-wraps to hold white lead along edge of your box with the other neutrals. Tom

[Van Huskey]

#3 and I would label it just so nobody ever is confused.

[Daniel Berlin]

I'm not an expert but I don't think you can do #2. I don't believe that the wires inside Romex are insulated or labeled for stand-alone use. Could be wrong.

I think #3 is the best option. Just put a wire cap on each end, coil it up neatly and put it it a corner.

You definitely can't do #2 unless the conductors are individually labeled. For starters, 110.3B requires you install a product per the listing and labeling, and you wouldn't be doing that (there are other code provisions this violates, but let's start there :P).


#3 is definitely the right option here.

[Joseph Tarantino]

+1 for #3. if you ever need a neutral, it's right there. cap both ends. that's what the licenses do in my jurisdiction.

[Mark Ashmeade]

Thanks guys. it turns out I can return the 6/3, and the job is now down with the correct 6/2.

[Bernie May]

I have done this exact thing (maybe three feet from outlet to panel) by just pulling the fourth, unneeded wire out of the sheathing.