Connected Home Charger - Speed Decreasing on 100A Circuit

[Chrome]

The question: is it a bug, or a feature?

Well, I took a look at my 14-50R outlet (Photo attached) and it certainly appears to resemble the lesser-quality version (Searched image LEFT). It does not have the additional clearance around the blades. I haven't removed the cover plate to inspect things further.

Of course I made it abundantly clear to the electricians that I would be charging an EV at 40A continuous, but apparently they cheaped out on the receptacle. 50A breaker was installed as expected, and I can only assume the choice of wiring was appropriate for the current (Have to question that now, too, I guess.)

This work was done in August of 2024, and the throttling did not begin until May of 2025. I'm led to conclude that, in my scenario, either:
A) The software was updated to actually respond to dangerously high temperatures at the outlet. I was just "lucky nothing happened" for the past year, as I regularly charged at 40A.
or
B) The software/Control Unit has always been capable of throttling this way, but the outlet finally became damaged enough (as of May, rather coincidentally) to cause excess/uncontrolled heat and now I'm seeing an automatic response to this.


Hopefully I'm not derailing the thread as it was originally discussing the LCHC in particular. Very similar symptoms, potentially different causes.

 

[Miami_Lucid_Man]

Well, I took a look at my 14-50R outlet (Photo attached) and it certainly appears to resemble the lesser-quality version (Searched image LEFT). It does not have the additional clearance around the blades. I haven't removed the cover plate to inspect things further.

Of course I made it abundantly clear to the electricians that I would be charging an EV at 40A continuous, but apparently they cheaped out on the receptacle. 50A breaker was installed as expected, and I can only assume the choice of wiring was appropriate for the current (Have to question that now, too, I guess.)

This work was done in August of 2024, and the throttling did not begin until May of 2025. I'm led to conclude that, in my scenario, either:
A) The software was updated to actually respond to dangerously high temperatures at the outlet. I was just "lucky nothing happened" for the past year, as I regularly charged at 40A.
or
B) The software/Control Unit has always been capable of throttling this way, but the outlet finally became damaged enough (as of May, rather coincidentally) to cause excess/uncontrolled heat and now I'm seeing an automatic response to this.


Hopefully I'm not derailing the thread as it was originally discussing the LCHC in particular. Very similar symptoms, potentially different causes.

No worries I think it’s worth discussing more than just the Lucid charger bc it’s happening on other chargers. The common thread among all posts seems to be the timing.

 

[DeaneG]

Well, I took a look at my 14-50R outlet (Photo attached) and it certainly appears to resemble the lesser-quality version (Searched image LEFT). It does not have the additional clearance around the blades. I haven't removed the cover plate to inspect things further....Hopefully I'm not derailing the thread as it was originally discussing the LCHC in particular. Very similar symptoms, potentially different causes.

I think it's good that you posted, as we can't automatically assume it's the car software.

My own guess is that ordinary thermal cycling on your oven-rated receptacle has loosened one of the wire connections enough to start causing a problem. There's enough copper around that when the receptacle overheats, the heat travels into the plug and cable, which you can feel.

One of many old threads on the issue: https://lucidowners.com/threads/har...ant-cooper-14-50-receptacle-not-leviton.6537/

 

[skomarla]

I was facing the same issue and flagged it to a mobile service technician who was seeing my car for a different reason. I provided date and time of each charge session when I plugged in, along with charge rate drop. He shared it with engineering and after 2-3 weeks, got back to me - "if it is warm inside the garage, the lucid charging station will drop the charge rate to cool down". He further told me "The best setting during the summer months should be around 56amps to avoid it overheating and throttling down."

I went ahead and changed the dip switch to 56amps and do not face the issue anymore.

well summer months is a bit of a generic term as temperatures do vary based on location. where are you located and how many cycles have you done at 56kw?

i'm not entirely buying that yet. in the northeast, a good summer day may still be cooler than a winter day in florida, arizona etc. honestly, i don't recall 18 dropping to 7 last summer. i would have noticed it at somepoint.

 

[Sandvinsd]

It is the car software cycling the amperage, probably heat related on the plug or the car itself. As for the last several months, ever since one of the updates (don’t remember which) my Lucid Home Charger will cycle between the 80 amps it is hardwired for down to 40 amps periodically. If I lower the amps on the charger to 40 or 45, it doesn’t cycle. I’m charging at night in coastal SD so it is not the garage being warm, although probably a combination of many things that the car senses to cause it to lower the amp pull.