Drop in maximum charging current

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RCH

***
Joined
Feb 26, 2021
Messages
4
When my 2019 e-Golf was brand new, its battery drew 32 A when plugged into my L2 home charger. This lasted for several months, after which I stopped monitoring it. Then I checked it again almost two years later, and the current was down to 24 A maximum. (This was a few weeks after a routine servicing.) The maximum current has held steady at the 24 A ever since. No adjustment to the charging station has been made, nor has it been networked or otherwise connected to another station. Does anyone have any ideas as to what the cause of the drop may have been?
 
Your e-Golf never took 32 amps. The on board charger accepts a maximum of 30 amps. (30Ax240V=7200W). You can pop the hood and look at the sticker on the charger if you don’t believe me.

What home EVSE do you use? If it can be configured to deliver multiple amperages, maybe someone else in your home dropped the max amps down to 24 amps?

How do you know your car is only receiving 24 amps?
 
Thank you f1geek for your reply. I'm learning more about my car all the time. I use a ChargePoint CPF25 charger. It's connected to a 208 V, "40 A" circuit (which actually carries 32 A, I think). 208 V x 32 A = 6.65 kW. (I live in a multi-family building with 120 V/208 V power lines.) According to the charger's spec sheet, it could alternatively be connected to a 20 A circuit, but I own my charger and it has never been reconfigured.

In the beginning I could only get the kW from ChargePoint's app. I'd then divide this by 208 V to get the current. I used to get a little more than 6.5 kW, which divided by 208 V gives 31.25 A. But, as you probably know, voltage fluctuates a little, so it may have been a little more that 208 V.

Later I became our strata's contact person with ChargePoint, which gives me access to much more data online, including kW, V and A. This was shortly before I noticed the drop in my charging current -- read directly from the online data. I have also read the current for other ChargePoint chargers in our parkade to be a LITTLE more than 30 A (e.g. 30.308 A), although I'm the only one in our building who drives an e-Golf.

I looked under the hood of my car, but couldn't identify the on-board charger.
 
Other cars may take more than 30 amps, but not the e-Golf (regardless of voltage) because the on board charger is rated for only 30 amps.

If you want to verify it can still take 30 amps, charge it at a public charging station that supplies 30 amps and see what happens.

Also, are you sure 208 V is correct? I am no electrician, but I have lived in a mutli unit dwelling and it had 240 V service. I thought 208 V is only for commercial buildings.
 
Good idea about trying my car on a public charging station. I'll do that.

I'm sure about the 208 V. I've spoken to an electrician about it, and he said that the 208 V is that between any two lines of the three carrying 3-phase current. I'm not sure why we have 3-phase in our building, but we do have a heavy-duty water pump. We also have the usual 120 V and 240 V, but our charging stations are wired to 208 V.
 
Ok. 208 V it is. I did a bit of research on 208 V and found that there is a 5% tolerance allowed for the service, so it could be anywhere from 198 V to 218 V. Assuming 30 amps, that is a range of to 5.94 kW to 6.55 kW. It could be something shifted with your building power supply and while it used to tend toward the upper end of acceptable voltage, it is now on the lower end of acceptable?
 
I tried charging my car on other stations, and on every one I get 30 A. Therefore the cause of the low charging current with my home station must have to do with the station, not my car!
 
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