hrc1079

Anyone experienced an issue like this? Plugged car in last night, charger activated, switch to 100% and charging timer was set to start at midnight. checked MyAudi app around 10pm and confirmed car was in “waiting for timer” mode.

Come out to car this morning and yellow light is on car. Didn’t really think much of it but realized when I drove off the car didn’t charge overnight. Got home and went to charge and charger wouldn’t even turn on. Checked switch panel to make sure circuit hadn’t tripped and all was good. It wasn’t until I pulled the cable out that I saw the plastic had been melted on the prongs.

The charger will work when switching to the 110 outlet but it appears either this cable is fried or the outlet is now blown. I’ll need to get an electrician in to take a look but this outlet has been working for 7 months with no issue so if there was a problem with the outlet it would have happened long ago. It’s like a surge was sent to the outlet.

I suspect if I go to Audi they’ll just blame the outlet but this seems really strange.

manitou202

This is a common issue with all EV's. It's usually the outlet. Most of the 14-50 outlets are poorly built and not really designed to handle continuous loads of 32+ amps for hours a day. They also typically don't handle plugging and unpluging frequently. Another cause can be the plug wasn't fully inserted. You need to make sure the plug is fully push in all the way.

You'll probably need to clean the leads on the charger (wire brush) and get a new outlet. Search online. There are high quality 14-50 outlets but they typically cost around $50-$75 versus the cheap $10 outlet. Here is an example on Amazon:

hrc1079

Thanks for the info. It hasn’t been unplugged since I got the car and was definitely fully inserted. I’ll get a wire brush and have ordered the outlet off Amazon. I know the electrician got the installed one from Home Depot. Hopefully the cable will still work as it’s $250+ to replace!

theo1000

I'm more concerned your breaker did not trip.

upgrade your breaker to one that is meant for heavy loads and can protect against arc faults. They are more expensive but electric over heating is main cause of home fires. Your electrician may not have understood the high sustained load and installed a standard breaker. It's quite easy if you want to do it yourself.

Tronification

Shouldn’t the EVSE itself have detected the overheating condition?

I remember reading that the Tesla charger had a temperature sensor that would cut off or throttle the charging if it detected an increase in the cable temperature. It may have been the car’s charging port rather than the EVSE, I don’t remember. Either way, I’m surprised that Audi’s charging cable is not smart enough to deal with that. It’s not like copper couldn’t conduct heat well enough to a sensor 2-3 feet away from the outlet.

It may be a good idea to not reuse the melted cable. Check with Audi and have them send you a new one to plug into your EVSE.

hrc1079

How a fire didn’t start is beyond me, nor do I understand why the breaker didn’t trip. If it was an electrician I’d never used before I would say they did a cheap and nasty install but this electrician is a commercial electrician that I’ve used for many years at work on much huger projects than a simple outlet install (server rooms, rack power etc.)

The wires have been burnt right through.

skaven81

That is terrifying. I'd also be really concerned as to why the breaker didn't trip. Is that 8-ga or 6-ga wire? My understanding is that 8-ga is acceptable for 50a peak loads, but that for sustained currents you need 6-ga to keep the cable temperature down. That said, the photo here looks like a full-on short circuit that vaporized the cable. That should definitely have tripped the breaker, I'd think.

yousufferbutwhy

Is that metal box not grounded either?

hrc1079

it’s grounded. That part is hidden in the wall

ThomasW

It is hard to guess just based on that picture. But the wires look really small. The ones I used appear to be substantially thicker. And the fact that they just melted through would also suggest they are to small.

This is the one I used: