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Discussion Starter #1
Outlets can be wired such that they fool cheap testers into reporting a connected ground when it really isn’t (e.g., wiring the neutral and ground posts together). More expensive testers will notice this and report an open ground.

Does the charger that comes with the Volt detect this problem? Can we trust it when it reports a connected ground?
 

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My utility treats the neutral and ground the same. But the tie cant occur outside the utility box. So a 240v with a neutral must carry 4 wires, ground, neutral and the two out of phase 120s. The ground and neutral are tied to the same bus bar only at the box, and are treated as their own, no jumpering allowed. The 120 is the same, minus one 120 lead.

I just modified my L1 clipper creak charger to L2, and it works perfectly.
 

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While by no means am I claiming safety, however my 1940s house that we were planning on moving from in a few months did not have a grounded garage outlet. I wired a jump from the neutral to the ground and it worked to allow the charger to operate. Previously I would get the red light indicating a ground fault. So to answer your question, at least in my case, that did trick the charger. Sadly the house selling process has taken longer than anticipated so I am still using that set up and I closely monitor the charging. Before we move I will be removing the wire and restoring the outlet to its previous state.
 

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ok, I'm curious to know how a more expensive tester can know the difference, and why you're concerned. GFCI breakers measure that hot to neutral (or hot to hot for 240V) current is equal. Generally, less than 5mA difference will pass (meaning minimal leakage to ground). Potentially a more sensitive tester can resolve better than 5mA, but do you really want to? Auto J1772 (the car side) does not have a "safety" ground. Tying neutral to ground at the EVSE plug (home side) means 0V difference and 0mA, which would fool any tester that does not have a separate earth safety ground input. 3 wire 240V EVSEs don't have a neutral, and have to return the Pilot signals 12V current to safety ground. Or 4 wire 240V EVSEs may have more load on one 120V leg than the other, for the internal control circuits.
 

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Discussion Starter #5 (Edited)
You're correct that more expensive testers may not catch it. I'm also not sure how they would. I got that from the following link, which I read too fast, apparently:

buellinspections.com/bootleg-ground-or-false-ground-on-3-prong-receptacles

It is my understanding that a GFCI without ground is mostly ok, but you can still get a short shock before the GFCI kicks in if a loose wire in an electrical appliance contacts the exterior. Plus, some appliances use the ground wire (e.g., computers that dissipate static electricity).

I'm mainly concerned that the charger is depending on the ground wire for some reason, and a false ground would cause problems.
 

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When I first got my Volt I had a boatload of charging problems, primarily because the garage was over 100 ft from my apartment. The only way I could get more than 30 minutes of charge time was to remove the ground fault outlet and make a little ac cord adapter that wired the ground and neutral together. Otherwise there was more than 10 volts difference between ground and neutral. Of course I had to redo that when I moved.
 
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