Electrical – Is it legal to add a jumper wire to a conductor that is too short in a junction box

electricalnecwiring

I live in Sparks, Nevada, and the 2011 National Electrical Code applies to me. My work will be inspected when complete.

I am replacing a switch and have found that someone before me (accidentally?) sliced open the insulation on the hot wire for the switch and neglected to fix it.

The slice only goes down a few inches of the wire, so I am considering cutting this off and just adding a jumper wire to it to extend it the required three inches outside the box (there will be enough wire to add a nut). Is this legal (per NEC 2011)? Specifically I am unsure if this a violation of the amount of wire I have to have coming in to the box.

See picture below, the slice is visible in the hot wire. It only goes as far as you can see in the picture and is intact after that.

enter image description here

Edit: Or should I just wrap it in electrical wire rated for at least 120V? My understanding is this is legal because it is in a junction box.

Best Answer

I think 300.14 is quite clear. You need at least 6" of free conductor, and the conductors must be long enough to extend 3" out of the box. If you can't pull more cable into the box, you're going to have to replace it.

As others have mentioned, 314.17(C) requires at least 1/4" of the cable sheath to be in the box. So the inspector might call you on that as well.