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very slow charging with NEMA 14/50 240 volts 50 amp

very slow charging with NEMA 14/50 240 volts 50 amp

I have a NEMA 24-50 240 volts 50 amp outlet installed in my garage. I am using gen 2 NEMA adapter. At first I was charging at 30-32 mph but now it has dropped to 7-8 mph. What has caused this to drop so much? How can I fix this?

Devilstower | 14. November 2019

When charging, can you check the voltage and amperage displayed by the car?

Passion2Fly | 14. November 2019

Several factors affect your charging speeds. Power stability, Voltage fluctuations, wire and plug overheating, car battery temperature, etc... when the charging power drops there is usually a message saying why the power dropped...

Magic 8 Ball | 14. November 2019

Need clarification. Does it charge at the low rate all the time now or just sometimes?

Frank99 | 14. November 2019

If your battery is almost fully charged (greater than 95% or so), the charge rate can drop significantly. If your battery is below that, it’s likely that the charger detected problems with the electrical circuit, and reduced charging current drastically.

Drive your car until the battery is below 75% or so, then plug in and pay attention to the charging screen. What does the voltage start at? Current should ramp up to 32A over a few seconds, then stay there. Voltage shouldn’t drop by more than a few volts as the current goes up. Let us know what you see.

Bighorn | 14. November 2019

Is the battery cold?

patelr1 | 14. November 2019

Thanks for your replies. The display shows 240 Volts. I don't know if the battery is cold. The plug or the charger is not hot.
It has been charging at only 7 mph since last week. No change no fluctuations.

bp | 14. November 2019

You should probably take a photo of the screen while charging and share a link to it, as it contains more information than you’ve provided so far.

jebinc | 14. November 2019

I humbly suggest you are plugged into a cheap $6 receptacle, whose resistance became high resulting in your car throttling back the amperage to the car. Consider replacing the receptacle with a quality unit.

Magic 8 Ball | 14. November 2019

It is definitely time to isolate variables. Check the “charger” on another outlet, go to a supercharger, have friend try their car on your setup, etc.

Lorenzryanc | 14. November 2019

I had a similarish problem with my Tesla wall charger. My screen showed ~220volts, but amperage would limit to 32 instead of the full amperage. Not 15-20 it looks like yours is doing, but still the car limited it. I got an error on the screen too. Turns out, as most forum peeps thought, loose ground wire. I opened the case, loosened every connection and tightened again. Problem went away and I can charge at max now.
You very well may have a loose connection or poor quality plug like @jebinc mentioned. Best case is try a friend's car on your system. *Make sure to cut power before doing any work on your outlet.

007bond | 14. November 2019

@bp is right take a pic of the screen to many factors. The car will automatically set the charge current lower if it sees a problem. So since you have not posted a pic did you at least make sure the charge is set for 32amps. It could have been and then the car seen an issue could be anything really and decided to drop the current setting down. If you find it set for lower and then set it up and it drops again you have maybe bad connection or your house is overloaded. We all need more info from you to really help or we are all just guessing in the dark.

kevin_rf | 14. November 2019

There is a bug that bit me where I fiddled with the start time before plugging in it would drop my charge current to 7a or 11a. Plug in, bring up the charge screen, see if you can thumb the value up to 32a.

Just my two cents, and it may not reflect your situation.

patelr1 | 14. November 2019

kevin_rf
Thanks for your tip. How do I "thumb up" to 32a??

kevin_rf | 14. November 2019
Joseb | 14. November 2019

While charging just press the "+" button next to the amperage.
It may have dropped by accident, or power fluctuation, for safety.

sowa.greg | 14. November 2019

One thing that has been mentioned a couple of times, but bears repeating since so many of the other replies go to more advanced troubleshooting that should only be attempted after checking the simplest potential source for a slower charge rate:
What do you have the charge rate set at in the car? Is it set to the full 32/32 amps that the Gen 2 mobile connector supports on a 50 amp circuit? Or, do you have it set to something lower than 32 amps? If so, bump that charge rate up and see if that solves your problem.

See the photo that @kevin_rf posted (you can get to that screen in your car by tapping on the battery icon).

bradbomb | 14. November 2019

Also, as others have said, do you live somewhere that the weather has gotten significantly colder? In colder temps if the battery is not warm already, the car will charge at a slower rate until the battery is warm enough to be charged at higher rates.

derotam | 14. November 2019

@patelr1: Are you not reading your thread over on TMC? I answered you there the same thing that kevin_rf said here.

anurags76 | 16. März 2020

Did you ever figure out the issue?