HPWC GFCI breaker trips only on Model 3 loaner, not on Model Y

[rwojo]

I've been using a HPWC on a 14-50, derated to 40A, as a temporary solution until I hardwire in a few units. Yes, technically this is not 1) to code and 2) can cause issues as the HPWC has ground fault protection built-in.

That said, it's been working for hundreds of charge cycles on our MY. It also has worked perfectly for a MX loaner we had.

A few days ago we got a M3 loaner and it trips the breaker ever night. What's odd is that it doesn't trip on every charge or any charge I can monitor, it only trips at ~5am. I've literally turned charging on/off 20 times in a row and it's fine at 40A. I don't have scheduled charging turned on, so the ~5am is quite arbitrary. My power monitoring doesn't show any current draw at that time. It's just a quick trip. So odd.

Anyway not a huge issue but curious what everyone thinks it could be, especially that it only happens on the M3 and not MX/MY.

 

[davewill]

Does anything else happen at 5am? We've seen weird things like a coiled up extension cord connected to lights on another circuit that come on at a set time causing nuisance trips of a GFCI. I suppose it could be a fault in the car where there's a small current leak to ground, although I have problems reconciling it with the timing of the symptoms.

Given that it's a loaner, if you can charge enough to use the car, I'd probably not worry about it.

 

[rwojo]

@davewill nothing I can think of, not even sunrise where automations adjust outdoor lights.

I have the car for one more day, if it happens between 5-5:10am EST I'm going to freak out...

... and then I'm going to return the car to the SA and get my MY back and cross fingers