Ground wire sparking

[Dave Dungan7]

Hello, I have a customer whose grounding wire at the sevice shows a spark every 20 minutes or so. The spark shows on the locknut for the connector of the Grounding electrode conduit. I checked everything for tightness and all seems good( the locknut was a little loose). Any ideas?

 

[chris kennedy]

Sounds like you maybe carrying someone else's neutral current.

 

[augie47]

also sounds like a violation of 250.64(E)

 

[chris kennedy]

After further review...

After further review...

Sounds like you maybe carrying someone else's neutral current.

If the above is your scenario, the GEC would be carrying the current, not the conduit. (Given all connections are good.)

 

[SG-1]

If the above is your scenario, the GEC would be carrying the current, not the conduit. (Given all connections are good.)

If the GEC is bare then portions of the conduit could be conducting portions of the current.

Place a clamp-on around it and see how much current is flowing & does it flow all the time.

What is turning on & off every 20 min ?

 

[LarryFine]

Dave, welcome to the forum!

It sounds like misdirected neutral current, as suggested in the above posts. Why the conduit, and not the wire? Hmm.

I suggest starting with a careful measurement of the line-to-neutral voltages at the panel, while under normal loading.

Then, depending on what you find, check every neutral and ground connection, from the meter to the water-pipe clamp.

 

[A/A Fuel GTX]

Hello, I have a customer whose grounding wire at the sevice shows a spark every 20 minutes or so. The spark shows on the locknut for the connector of the Grounding electrode conduit. I checked everything for tightness and all seems good( the locknut was a little loose). Any ideas?

Just curious.....what grounding electrodes are present? I just did a panel changeout where the where the GEC was carrying 4 amps from the water pipe to the grounded conductor of the service.