In the winter I repeatedly get intense static discharge shocks from the faceplate screws in my basement light switch panels (which are grounded metal boxes, unlike the plastic ones used in non-basement locations). Is there any good reason not to replace the screws holding the faceplates on with non-conductive ones? Are matching (size and thread) plastic screws available? Or is there some other clever solution to the problem that's not ugly or dangerous?
Electrical – Unwanted grounding from metal screws in metal boxes
electricalgrounding
Related Solutions
Here's a diagram covering the grounding possibilities. There are new clarifications about lighting protection and grounding in the NEC 2017 code. By the way NEC 2017 becomes law in this state today.
Hope this helps. Good luck.
Yes, it's allowable to tie a ground wire to a junction box and let the metal conduit carry it the rest of the way back.
However, if the ground wire is already in the pipe, I'd leave it in there - belt and suspenders - unless you need the conduit fill.
You terminate a ground wire at a junction box by attaching it to a ground screw. Virtually all junction boxes have a hole tapped #10-32 specifically for ground screws, which are sold either with or without pigtails. You can put 1 wire on that screw, or any sensible number of ring terminals. Make sure the ring terminals are UL listed for use in mains power.
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Best Answer
I think the clever solution you're looking for is covering the screw with a square of white electrical tape to prevent yourself from touching the screw.
You could also purchase nylon 6-32 machine screws with a flat head which are non-conductive.
That only fixes the sympom of the problem, but not the cause. Your excessive static electricity is from low relative humidity levels in the air. Increase it to 30-40% RH and you'll be happier.