Ground assurance fault. Wall charger.

[MarkMuhlbaier]

Just installed a wall charger with 6/2 wire 60 amp breaker. I’m getting a ground fault code, high ground resistance detected. My question is, my ground wire in the 6/2 wire too thin (small)? Or my ground buss in the sub panel has some neutrals attached with ground wires. Could that be the issue? Thanks

 

[orntar]

Did you install a arc fault breaker or gfci breaker? I would make sure all connections are very secure first.

Next would be call an electrician to check it all over.

 

[Sophias_dad]

No, the ground wire is not too small. 10AWG is normal. It doesn't carry any continuous current.

My best bet is one or the other end isn't actually connected(hard to believe).

There shouldn't be a fancypants GFCI or AFCI breaker in use, just a $20 home depot special.

There is something funky about your subpanel, too. Pretty sure the ground and neutral should be separate all the way back to the main panel, so if you have comingled grounds and neutrals someone did some shortcutting.

 

[MarkMuhlbaier]

Did you install a arc fault breaker or gfci breaker? I would make sure all connections are very secure first.

Next would be call an electrician to check it all over.

It’s just a regular breaker.

 

[MarkMuhlbaier]

No, the ground wire is not too small. 10AWG is normal. It doesn't carry any continuous current.

My best bet is one or the other end isn't actually connected(hard to believe).

There shouldn't be a fancypants GFCI or AFCI breaker in use, just a $20 home depot special.

There is something funky about your subpanel, too. Pretty sure the ground and neutral should be separate all the way back to the main panel, so if you have comingled grounds and neutrals someone did some shortcutting.

I wouldn’t doubt some short cutting. I did read somewhere the neutrals and ground at times can be connected? Just didn’t know if the smart Tesla charger doesn’t like that.

 

[Sophias_dad]

It’s just a regular breaker.

And lest we forget, 6-2 NMB is really only supposed to have a 50 amp breaker and 40 amp HPWC setting.

 

[MarkMuhlbaier]

No, the ground wire is not too small. 10AWG is normal. It doesn't carry any continuous current.

My best bet is one or the other end isn't actually connected(hard to believe).

There shouldn't be a fancypants GFCI or AFCI breaker in use, just a $20 home depot special.

There is something funky about your subpanel, too. Pretty sure the ground and neutral should be separate all the way back to the main panel, so if you have comingled grounds and neutrals someone did some shortcutting.

All connected secure.

 

[MarkMuhlbaier]

And lest we forget, 6-2 NMB is really only supposed to have a 50 amp breaker and 40 amp HPWC setting.

I can switch the breaker. Just need to figure out this fault soon.

 

[Rocky_H]

Or my ground buss in the sub panel has some neutrals attached with ground wires. Could that be the issue?

I wouldn’t doubt some short cutting. I did read somewhere the neutrals and ground at times can be connected? Just didn’t know if the smart Tesla charger doesn’t like that.

Hmm, that might be related to your issue. It's certainly a code violation regardless. The code thing you are thinking of is this:
Neutral and ground must be connected at ONLY ONE place in your house--the main service panel. They must be tied together there and never at any other subpanels anywhere else. Neutral and ground need to be kept separate from each other all through the rest of the house.

(Theorizing...) Perhaps if they are tied together in a subpanel, the ground check ends up running through a lot of extra neutral paths through your house and other circuits, which makes it seem to have a lot of extra resistance.

 

[earthwormjim]

You need to get a multi-meter and actually check if there is poor continuity between the ground at the wall charger, and the ground bar in your panel. Probably a long stretch to probe these two points, so just hook up a long ground conductor to the ground bus, and use that to help probe.