Level 2 240 EVSE that charged a Volt will not charge a Bolt

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May 17, 2018
I have a SPX (now Bosch) Power Xpress 240 volt 30 amp 7200 watt charger which I have used for Level 2 home charging of 2 Volts (a 2013 and a 2015 -- total of 6 years). The charger was professionally installed on a 200 amp service panel, with 6 AWG Al wire, and a 30 amp breaker. I have never had an issue with the charging. I just got a 2017 Bolt and, when I plugged it in at home to make sure no problems with my home charger, the charger gave me a Ground Fault Detection. I followed the SPX instructions, making sure the EVSE connector and the vehicle's charge port are both clean and undamaged, and tried again with the same result. The dealer must have had no problem charging it since it was fully charged when I picked it -- yet the charger charged my 2015 Volt with no problem the same day.

I plan on contacting SPX and the dealer about it, but was hoping someone on the forum might be able to give me some insight on what the problem might be and, moreover, who should I see about problem identification and resolution. I am afraid I am going to get the run around -- I.e., the dealer will say it's my charger, the charger manufacturer will say its my vehicle, etc.

Any info or guesses will be greatly appreciated.
Just to be clear, the charger is built into the car. This is a case where it is not semantics as it is possible the Bolt charger is indeed faulty and when relaying symptoms to the dealer and/or EVSE manufacturer it is important to differentiate.

You also state that the 30 A (7.2 kW) EVSE is installed on a 30A circuit. Your wire size is fine, but the breaker needs to be 40A, not 30 (EVSE's are considered continuos duty devices and the breaker needs to be at least 125% of the max load).

The Volt draws about 1/2 the amperage of the Bolt when charging, and that could be a contributing factor as pulling the full 30A from the EVSE could be causing a fault that wouldn't show up when charging the Volt.

If your Bolt charges on other L2 EVSE's with no problems, it kind of points to your setup. Although the J1772 standards are pretty simple, sometimes odd incompatibilities show up between certain EVSE's and vehicles.

IIRC, there was another brand of EVSE that needed an upgrade to work with the Bolt as it was also overly sensitive and throwing a ground fault error. I can't remember the brand at the moment.
Thanks DucRider. I queried the web about a possible upgrade to the Power Xpress EVSE and found that this EVSE was under a NHTSA safety recall. It works fine for Volts (and other EVs drawing 16A or less), but causes fires or meltdowns when used with EVs drawing 30A or more. It melted the vehicle connector on an EV drawing 30A and injured an owner trying to remove the melting J1772 connector. Bosch offered a field upgrade to resolve the problem. Unfortunately, I have no record of ever receiving the notification letter. Fortunately, the ESVE unit failed to charge because of the GFCI tripping. Whether the GFCI tripping is due to the recall problem or something else like the 30A instead of 40A breaker is TBD.
Hi Dennis.

You neglected to specify whether your particular SPX has the standard NEMA 6-30 plug (30 amp plug and cord). If so the rotary switch under the escutcheon will be set to 24 AMPERES, maximum. ONLY hardwired SPX's were ever set to 32 amperes.

In my experience BOSCH SPX's are notoriously unreliable and the first thing to check is, does it work with ANY ev Still? #6 is certainly fine for 40 amperes but make sure the electrician shined and greased the aluminum wiring with a wire brush and NO-OX. I looked at the manual for this BOSCH POWER XPRESS unit, - the internal terminals seem really chintzy - make sure your electrician put a copper pigtail on the wires if this thing was directly wired, and that all of his splices are good - especially the aluminum to copper pigtail ones.