Stuck relay tends to happen when the push button on the handle is not working correctly and the handle is unplugged under load. We would recommend checking that the push button is clicking before unplugging the vehicle and the current drops to 0.
Thanks for the info, but I don't think that applies here because when a charging session "fails", the handle has not been touched.
I didn't clearly explain the order of events. A session goes like this:
The EVSE remains plugged into the garage wall (NEMA 14-50) from the last charging session
I plug the J-1772 into the car
It starts charging the car (light blinking)
The handle is left undisturbed.
Sometimes, when I check back later, the car has stopped charging (light not blinking)
I unplug the J-1772 from the car
I unplug the EVSE from the NEMA 14-50
I wait 10 seconds
I replug the EVSE into the NEMA 14-50
I replug the J-1772 into the car
It starts charging again (car light blinking)
It almost always then charges without further problems until the end of the session
I actually rarely charge at home, so this has gone on for many months, but probably less than 40 charging sessions. I estimate that "failures" occur on about half of the sessions (I think I'll start charging more often at home so I can get a better handle on how often it happens).
On a recent "fail", I finally thought to look on my phone display and it said "Stuck Relay" (screenshot in original post)
Could it be a defective relay?
When it stops charging do you get an error such as "No Ground"? Maybe this issue to increase relay hold power?