For the past week or two, I noticed that my spouse’s EV hasn’t had the battery levels that I normally expect to see, later in the day. Two days ago, I noticed the house lights brighten a bit, as usual, between 1 and 2 am, and quickly checked the charge level, and saw that it was at least 50 miles short of a usual charge.
I didn’t think much of it, assuming that I had to change the settings to have the car charge itself more fully (it lets you set a max charge level, and the manufacturer recommends a setting that is not too close to a full charge as that would shorten the battery life).
Last night, by the time I remembered to make those changes, the car had already finished charging (it is set to start charging at midnight, at a current of 80 amps). This time it was closer to 100 miles short of a regular charge. I tried to get the car to start the charging process again, using its iPhone app. The car acted as though it wasn’t plugged in. I walked to the car in the garage, and shortly realized that the wall-charger was not powered. I went to our house’s main panel, and the charger’s circuit breaker hadn’t tripped. I tried to toggle it on and off and it wouldn’t budge. And that’s when I noticed that telltale stench of burnt electronics. (what exactly is that?)
Later, in daylight, I opened the panel and saw the mess. Although I don’t have a picture of the panel as it was this morning, I do have the circuit breaker, which was replaced, and I am sharing some photos:
This is what I think happened. Due to the heat generated when 80 amps flows through this circuit breaker, the contacts on one side would expand enough so that an arc would occur between it and the panel’s power bus. This arc is what burned the circuit breaker. It’s either a defect in the circuit breaker, or the breaker isn’t fully compatible with the power panel ( I don’t think that the power panel and the circuit breaker are made by the same manufacturer – but who knows, they may have been built in the same Chinese factory).
I am not sure how long this was going on, but one thing I do know is that the charging unit, or the car, most probably noticed the erratic flow of electricity. And it did an admirable job of filtering out the problem and even ending the charging process when it detected some disturbance. But what it really should have done was to send me a little notice that, due to power fluctuations, it interrupted the charging cycle, and recommend that an inspection be performed. No?