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Melted Charging Adapter/Cord

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For peace of mind, I have dialed the charging current down to 30A. 30A produces approximately half the heat compared to 40A while yielding about 22 miles/hour of charging using a NEMA 14-50 setup. For my daily 60 miles commute (and occasional 100 miles), 30A works just fine for me.
 
I would have an electrician do a load test on your outlet. Two possible causes for this type of failure - bad contact between plug adapter (socket) and the UMC plug or in a 240V circuit one side is carrying all the power versus the other side of the circuit. US 220-240V is +120V one side to -120V the other side.
 
I felt my outlet and plug end yesterday and it is barely warm after charging for a couple of hours at 9+ kW. I do have a really short run from my main panel to sub panel ~ 6 ft of 6ga and ~ 2 ft of 8 ga for the 14-50. Wonder if some anti-ox electrical contact grease stuff would help/fix this problem.

I have a UMC plugged in always at my house. It might be a good idea to get rid of the adapter and hardwire it to the breaker panel but then it wouldn't be covered by Tesla if the fault circuit breaks or something.
 
They will not replace it every time. Service was able to determine that it was an issue with my outlet by sending an electrician. There was too much current to one prong causing an overheating issue.

I don't understand that comment. The UMC only uses two power pins; the current that goes in one goes out the other. If there is ever an imbalance in the current through the power pins, it will cause a ground fault and the UMC will stop the current. I do not think that it is possible to have too much current in one pin of the receptacle without too much in the other.

Perhaps, it was too high a resistance on the connection to one pin of the receptacle causing the overheating. This could be caused by a poor installation and has been seen elsewhere.
 
That is BS - there is equal current going to each prong. The fact is that one prong had a high resistance connection which led to overheating.

Whether Tesla replaces the UMC under warranty depends on where the melting is. If its on the wall outlet side, it probably won't be replaced under warranty. If it's between the UMC and the adapter like the above pictures, it will be replaced under warranty. It's not BS if Tesla refuses to replace UMC's that burnt due to crappy house wiring.
 
Look at what the media did with just three Model S fires. Imagine what they are going to do when someone's house burns down because Tesla made a lousy UMC adapter. Tesla should recall these parts immediately and replace them with a more robust design. A garage fire from a month ago appeared in the media in the last week, then Tesla hastily sent out a software update to reduce charging by 25% if the car notices a fluctuation in the current. While I applaud Tesla for the fast and proactive response to mitigate an external power issue, there are plenty of reports here in the forums about UMC adapters melting to throw some culpability back in Tesla's direction.
 
Whether Tesla replaces the UMC under warranty depends on where the melting is. If its on the wall outlet side, it probably won't be replaced under warranty. If it's between the UMC and the adapter like the above pictures, it will be replaced under warranty. It's not BS if Tesla refuses to replace UMC's that burnt due to crappy house wiring.
The "BS" was in relation to Tesla's explanation of the issue which is physically impossible - not with the lack of replacement. Cottonwood explained it much more eloquently than I. :smile:
 
The "BS" was in relation to Tesla's explanation of the issue which is physically impossible - not with the lack of replacement. Cottonwood explained it much more eloquently than I. :smile:
Who knows what Tesla actually said. Anyone can post anything on the internet, and the stories get bigger with time. On the other side of the coin is the fact that not all Tesla employees know what they are talking about.
 
Apparently some people weren't pushing it in all the way until it clicked. Even the best engineering in the World can't overcome "dumb".

To be fair, the adapter has about 2-3mm of play when it's locked in. Unless you know about the melting issue, it's not obvious that it must be pushed together completely. Now, melting multiple UMC's after being told this would be "dumb".
 
To be fair, the adapter has about 2-3mm of play when it's locked in. Unless you know about the melting issue, it's not obvious that it must be pushed together completely. Now, melting multiple UMC's after being told this would be "dumb".
Huh. I guess I hadn't noticed. I read about the Melting adapters here on the forum. When I went out to check mine it was already fully seated and I never bothered to pull on it to check for free play. If that's the case, then I agree, closer tolerances would definitely be in order. The last thing TSLA needs is to have another Garage fire and have it tied directly to the charging cable this time. The media would of course tie the two fires together regardless… Definitely a concern.