Charger Faults on 2 Different L2 Chargers

[GlennD]

This is harder. Measure the voltage from the circuit breaker buss to the breaker output. For both buss's it should be near zero. If it is good then measure the garage panel. If you find a fault it may be the interconnecting cable. Hopefully the cable is good with no splices. Somewhere you have a problem. If you are very lucky it will be in the panels not the buried cable. A digital meter samples the voltage.I The two phases ( not really ) must be about the same. If one side is erratic then that is the problem. Unlike an analog meter a digital one periodically samples the voltage . That may disguise. the problem.

 

[GlennD]

This is harder. Measure the voltage from the circuit breaker buss to the breaker output. For both buss's it should be near zero. If it is good then measure the garage panel. If you find a fault it may be the interconnecting cable. Hopefully the cable is good with no splices. Somewhere you have a problem. If you are very lucky it will be in the panels not the buried cable. A digital meter samples the voltage. Ihe two phases ( not really ) must be about the same. If one side is erratic then that is the problem. Unlike an analog meter a digital one periodically samples the voltage . That may disguise. the problem.

 

[GerryAZ]

This is hard to explain in a few words, but I will try. I am concerned that the bare neutral conductor is acting like a neutral grounding electrode for the whole house and seeing fluctuating current to ground caused by changing loads in the house. Since the EVSE checks for a safety ground connection by injecting a small current from line to ground, fluctuating current in the bare conductor might cause the EVSE to shutdown. This would be less likely to affect the 120-volt EVSE because the ground sense current is from only one line to ground and the 12 amperes of continuous return (neutral) current on the bare conductor would tend to dampen the fluctuations. I have seen severe unbalance between the two 120-volt lines and damage to metal water pipes from inappropriate ground currents caused by loose or inadequate neutral and ground connections. As others have already noted, the feeder to the garage should have 3 insulated conductors (L1, L2, N) and a dedicated ground conductor.

Gerry

 

[glubash]

I am having the same “abnormal current (scp)” fault using a Zencar evse. The car will charge up by some amount and then the charger will cut out on a fault. I’ve had it fault out after less than 30 minutes up to after a few hours of charging. So far, I’ve tried 2 different units and had the same problem.

The fact that the car usually charges most of the way before the fault occurs leads me to believe that it is not the wiring (I am using a NEMA 6-20 receptacle with 2 hots and a ground, no neutral). Additionally, outlet is less than a foot from my 200 amp service panel.

Did you ever figure out the problem or a solution?

Thanks!

 

[LeftieBiker]

I seem to recall a case or two in which a high amperage device that was not on the same circuit, but was on the same panel, was causing an EV to fault out because of surges and/or voltage drops that affected other circuits. Do you have something that uses huge amounts of power and switches on and off at roughly the same interval?