I have a metal junction box but I'm currently using as a pass-thru for the wires running through it. It's the incoming box from outdoor underground conduit burial. My ground wire is just barely long enough so I'm afraid to splice it and reconnect it using a wire nut so the box can be grounded. Is there a way to splice it securely so I don't have to worry about the splice coming loose? If not, can I just run a 4th wire from the jbox to the panel and consider it grounded safely?

I do have the hot wire in the box with a wirenut right now because it was a couple inches short so I had to cut it and extend it.

  • 1
    I'm confused. What is the ground wire connected to now? A photo would be the absolute bomb.
    – isherwood
    Dec 12, 2017 at 21:13
  • 1
    I don't think you have to ground the metal junction box if all the wires in it are just passing through since you don't have any splices in it. It's basically just a pull point.
    – Dotes
    Dec 12, 2017 at 21:21
  • I agree with Jeff no splices no ground needed its just a pull box.
    – Ed Beal
    Dec 12, 2017 at 21:42
  • I have ONE wire that is not just passing through. I should've clarified that. My hot wire is actually on a wire nut but it's long enough so I felt comfortable using a wire nut for that Dec 12, 2017 at 22:30
  • 1
    Jeez, I guess I could just buy another $8 worth of #10 cable and push that through. I just feel like I've been defeated if I do that ;) Dec 12, 2017 at 22:48

2 Answers 2


If that wire nut comes loose it sounds like you could end up with not only a HOT BOX but perhaps HOT CONDUIT also.

I trust you can imagine the possibilities of misfortune that can result from that.

It is well worth whatever it takes to prevent that from happening. What you want is to have a breaker trip instead.

Splicing ground wire is safe when done correctly. But if your length simply can't reach or if the splice can't be made to fit inside the conduit, then the only option would be a new length of ground wire.

Call it cheap insurance.

  • 3
    A parallel tap would be appropriate and legal. Ideal part # GP-2 Catalogue # 87-150.
    – Paul Logan
    Dec 13, 2017 at 6:14
  • @PaulLogan You should make you're an answer... that's exactly what I was looking for although I ended up just buying new wire since it was a pretty short run anyway Dec 13, 2017 at 14:56

Here are some pertinent articles of the National Electrical Code:

314.4 Metal Boxes. Metal boxes shall be grounded and bonded in accordance with Parts I, IV, V, VI, VII, and X of Arti‐ cle 250 as applicable, except as permitted in 250.112(I).


250.148 Continuity and Attachment of Equipment Grounding Conductors to Boxes.

If circuit conductors are spliced within a box or terminated on equipment within or supported by a box, all equipment grounding conductor(s) associated with any of those circuit conductors shall be connected within the box or to the box with devices suitable for the use in accordance with 250.8 and 250.148(A) through (E).


If not, can I just run a 4th wire from the jbox to the panel and consider it grounded safely?

You should run another equipment grounding conductor from the panel to the box. Then splice the equipment ground and bond it to the box with a #10/32 green grounding screw in the tapped hole in the box.

Good luck!

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service and acknowledge you have read our privacy policy.

Not the answer you're looking for? Browse other questions tagged or ask your own question.