Gen 3 Wall Connector pulling 105 Amps?

[Big Earl]

I'm not sure 105A going through a 50A breaker would actually trip it


I think it might be something more like this:

View attachment 878066


View attachment 878068


View attachment 878069


...and no, this has nothing to do with my or anyone else's EV

105 amps through a 50 amp breaker should absolutely trip it nearly instantly. Your picture shows an FPE breaker, which are infamous for being defective and not tripping.

 

[qdeathstar]

I had the same question for my electrician (reputable company that’s done work for me before). His response was - shrug, they don’t trip immediately. He also replaced the breaker and found the same overage.

Could his amp meter be wrong, sure. But the burning smell lends credence to something going awry.

I’m just really confused at this point so if the answer is “send another electrician out” that’s fine.

At 100 amps the breaker is going to trip in under 15 minutes, even if you live in an igloo.


But if we assume he is correct, then you have a few options as to where the power could be going. The most likely option is that the circuit to the EVSE is not actually dedicated and was tapped off an AC or something else. There is also a possibility that there is a nail or something that has damaged the wiring to the evse and there is high resistance current flow at that spot. That would be rare.

Did he check the voltage at the panel and at the evse? Maybe he was reading 105v which would indicate a different problem.

 

[qdeathstar]

I wonder if he had the meter set to hold the max value. If it got a reading during an arch event, it's possible he did get an instantaneous reading of 100amps.

Good point.

 

[EVer Hopeful]

At 100 amps the breaker is going to trip in under 15 minutes, even if you live in an igloo.

I'd hope it would be a little faster than that

 

[qdeathstar]

I'd hope it would be a little faster than that

I mean it is thermally activated so the ambient temperature will affect how fast it will trip.

 

[qdeathstar]

I'd hope it would be a little faster than that

https://goodsonengineering.com/wp-content/uploads/2017/08/CircuitBreakerMyths_web.pdf

This seems to say it could take up to 6 minutes. But if you factor in extremely cold temps I could probably take a little longer.

 

[MN-MS100D]

Never mind.

 

[IchDochNicht]

...Gen3 wall charger ...firmware set to limit charging to 40A.

How did you set the firmware to 40A? I just had a Gen3 charger installed with a NEMA whip, and it delivers 48A instead of the proper 40A. We could not find a way to set a limit.

Thanks!

 

[WilliamG]

How did you set the firmware to 40A? I just had a Gen3 charger installed with a NEMA whip, and it delivers 48A instead of the proper 40A. We could not find a way to set a limit.

Thanks!

That's in the commissioning procedure, once online.

https://www.tesla.com/sites/default/files/support/charging/Gen3_WallConnector_Installation_Manual_SG.pdf