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I'm on a road trip and have used two public EVSE's in a row (both Chargepoint) and have had similar results. At the first charger a Level 2 rated at 6.6 kW/h I charged at a rate of 3.3 kW/h. I'm now connected to a DC fast charger rated at 62.5 kW/h (I know I won't get above 50, but I wanted to try to be thorough) and I started at just over 20 kW/h and am now at roughly 25 kW/h, after about 20 minutes.

I'm assuming that my onboard charger has lost a leg. By which I mean was charging at 120V on the level two charger instead of 240V. I don't know what the voltage on a DCFC is.

Is there a fuse that could have blown, or does this mean that I'll need to get the whole unit replaced?
 

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12/16 build, 2017, white LT
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I'm assuming that my onboard charger has lost a leg. By which I mean was charging at 120V on the level two charger instead of 240V.

I don't know what the voltage on a DCFC is.
I am pretty sure, that is not what is going on.

In any event the onboard charger being damaged would not effect the DC charging, which completely bypasses the onboard charger. How cold is it? What SoC were you at during these charge events?
 

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I'm on a road trip and have used two public EVSE's in a row (both Chargepoint) and have had similar results.
Does your Bolt have the new fire recall battery? Pop the hood, and look at the coolant level in the battery coolant loop reservoir. Is it at least up to the line with the two arrows, just above the hose, or below the hose?

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There is nothing wrong with your car.
It can be the chargers themselves + the cold battery. Not all L2 chargers give you 7 kW nor all the 65 kW output DCFC give you 52 kW.
 

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I have seen kyle Conner say many of the DCFast chargers rated at 62kW rarely put out that much, many never get over 40kw, in fact there is a Chargepoint one I have used several times with my previous Spark EV and my Bolt and never seen over 38kW out if it.
 

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I'm on a road trip and have used two public EVSE's in a row (both Chargepoint) and have had similar results. At the first charger a Level 2 rated at 6.6 kW/h I charged at a rate of 3.3 kW/h. I'm now connected to a DC fast charger rated at 62.5 kW/h (I know I won't get above 50, but I wanted to try to be thorough) and I started at just over 20 kW/h and am now at roughly 25 kW/h, after about 20 minutes.

I'm assuming that my onboard charger has lost a leg. By which I mean was charging at 120V on the level two charger instead of 240V. I don't know what the voltage on a DCFC is.

Is there a fuse that could have blown, or does this mean that I'll need to get the whole unit replaced?
Lots of L2 stations that have two leads on them are power sharing. You'll only get 3.3kW on those stations if another vehicle is plugged in, since it's sharing 6.6kW.

You can't lose a leg, only the hots are connected with a 240V connection. Neutral doesn't even have a place to be landed.
 

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Charging rate is measured in kW, not kW/h (which makes no sense in this context).

It actually is kWh/h, but h/h cancels out --> kW.
It's 37 degrees F and I was at about 34% of charge for both.
Even on a sufficiently powerful DC FC (e.g. 100+ kW), at low SoC, you may not be able to hit 55 kW due to throttling since it's so cold, likely to prevent lithium plating. See page 10 (lower right page numbers) of https://acep.uaf.edu/media/304144/Cold-Weather-Issues-for-EVs-in-Alaska.pdf.

If you used the peak charging rate of 55 kW and assumed 65 kWh battery, that would be a C rate of 0.846. Peak charging rate of 65 kW (Bolt can't go that high) with 65 kWh battery would be 1C. I don't know if C is counted by peak vs. overall charging rate.
 
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Lots of L2 stations that have two leads on them are power sharing. You'll only get 3.3kW on those stations if another vehicle is plugged in, since it's sharing 6.6kW.
Indeed. CT4000 Family | ChargePoint if only given a single 40 amp feed instead of a 40 amp feed for each handle will yield charging power cut in half on both sides if both sides are charging. We had that at my work for a few weeks on 3 stations.

One can also look at the data sheet via CT4000 DS US-EN.pdf | Powered by Box.

And, years ago, CP added Charge More EVs with Power Management | ChargePoint. We had to use the equal share algorithm (was super buggy, long story) for awhile which in theory is supposed to do this:
"Site sharing sets a power ceiling to limit the aggregate instantaneous load for all charging stations if the overall power available at a site is limited by a transformer."

Basically, it is supposed to drop the power output (what the EVSE's pilot advertises) to keep the bank of EVSEs under a certain power ceiling.

There's also Share2.
 

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When the battery's temperature is at 10C (50F) or below, the maximum DCFC charging speed of a Bolt gets limited to about 21kW and then slowly climbs up as the battery heats up. What you've reported is perfectly in line with what you should experience in winter and there's nothing wrong with your car.

I've actually touched on this on one of my videos... It's in Korean, but turn the translation on for the subtitles and take a look at the graphs. Here's the link that goes to the relevant part at 06:07.
 

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Discussion Starter · #13 ·

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It does have the new battery. The recall was performed a few months ago. I will check the coolant.

Are you, by any chance, in the car when it is being charged? Like sitting in the car with the car on?

While the DC is explained by cold battery and slower charging until the batt temp is at least 16 C, the Level 2 could be explained by simply You sitting in the car with the car on.
If the car is on, it will start warming up the battery and use energy to heat the cabin.

Eventually, if it is a dual charger (two sides) then you might be getting half while the other car gets half as well.
 
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When the battery's temperature is at 10C (50F) or below, the maximum DCFC charging speed of a Bolt gets limited to about 21kW and then slowly climbs up as the battery heats up. What you've reported is perfectly in line with what you should experience in winter and there's nothing wrong with your car.

I've actually touched on this on one of my videos... It's in Korean, but turn the translation on for the subtitles and take a look at the graphs. Here's the link that goes to the relevant part at 06:07.
@wesley Incredibly factual and documented information! I loved the video!
 

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Could you please clarify that statement? It could be read in another way, which would be ridiculous.
some public chargers are 6.6 kW (32 A at 208 V), but it is a split between two plugs. If only one is plugged in - you get 6.6 kW, but if someone starts using the other plug - you split the load and each gets 3.3 kW.
 
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some public chargers are 6.6 kW (32 A at 208 V), but it is a split between two plugs. If only one is plugged in - you get 6.6 kW, but if someone starts using the other plug - you split the load and each gets 3.3 kW.
Thanks for that explanation. My reading was that you were referring to the (level 2) GM dual charger.
 

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Thanks for that explanation. My reading was that you were referring to the (level 2) GM dual charger.
now I see it :D
yup, possible...
 

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Discussion Starter · #20 ·
Thanks to all of you for your help. I hooked up to a charger today and charged at full rate for 8 hours.

The consensus was correct, nothing was wrong with the car. I was extra anxious because I was on a road trip but everything worked out!
 
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