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So, I have gotten my Juicebox running at it's max rating of 32 amps. According to the Juice Net web site it charges the car at 7.5 kW. (Typically 31.6 amps at 237 volts, assuming the Juicebox meters are correct.

The other night I was taking the dog out to her yard when I noticed a lot of noise coming from the Bolt. The Juicebox showed that it was still charging but the car said it was done. I pulled the power cable and the sounds stopped so I plugged it back in and shrugged it off.

Last night I again was taking the dog out and the Bolt was making noise, so this time I opened the hood. The A/C was running and the coolant loop for the power electronics was plugging away and the coolant was warm but not hot. While I was looking at things, it all stopped.

Now its a little warmer than it has been, it was about 90 when charging started and about 80 when I was checking it out. 7.5 kW is a lot of power to convert, so I can see the power electronics needing some cooling. But the A/C heat exchanger that cools the battery was active and quite cool. So was it needing to cool the battery? That doesn't seem right if the battery can charge at 50 kW that 7.5 would make it hot enough to need cooling.

Here is a chart of the charging session:

So, charging started at 6:00 and ran until about 9:50 at about 7.5 kW. Then it looks like the car stopped charging but continued to pull power until 10:15 or so. So for 25 minutes the car was pulling over 1.25 kW for dissipating heat from the charging. (The chart says that comes out to about 0.8 kWh, so not much financially.)

So here are the questions:

Is this expected?

Is the A/C running unexpected?

Should I lower the charge rate?

What do you guys think?
 

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Once the battery is done charging but the car is still plugged in, it will start cooling the electronics and battery. Unless necessary it won't do this while charging so as not to slow down the charge, but once the charge is complete the car will cool things down to a more optimal temperature with the wall power now available. When you pulled the plug that power was no longer available so the car stopped chilling things.
 

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2020 Chevy Bolt and all Tesla models owned by me and my family
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So, I have gotten my Juicebox running at it's max rating of 32 amps. According to the Juice Net web site it charges the car at 7.5 kW. (Typically 31.6 amps at 237 volts, assuming the Juicebox meters are correct.

The other night I was taking the dog out to her yard when I noticed a lot of noise coming from the Bolt. The Juicebox showed that it was still charging but the car said it was done. I pulled the power cable and the sounds stopped so I plugged it back in and shrugged it off.

Last night I again was taking the dog out and the Bolt was making noise, so this time I opened the hood. The A/C was running and the coolant loop for the power electronics was plugging away and the coolant was warm but not hot. While I was looking at things, it all stopped.

Now its a little warmer than it has been, it was about 90 when charging started and about 80 when I was checking it out. 7.5 kW is a lot of power to convert, so I can see the power electronics needing some cooling. But the A/C heat exchanger that cools the battery was active and quite cool. So was it needing to cool the battery? That doesn't seem right if the battery can charge at 50 kW that 7.5 would make it hot enough to need cooling.

Here is a chart of the charging session:

So, charging started at 6:00 and ran until about 9:50 at about 7.5 kW. Then it looks like the car stopped charging but continued to pull power until 10:15 or so. So for 25 minutes the car was pulling over 1.25 kW for dissipating heat from the charging. (The chart says that comes out to about 0.8 kWh, so not much financially.)

So here are the questions:

Is this expected?

Is the A/C running unexpected?

Should I lower the charge rate?

What do you guys think?
If not necessary to run at 32 max .
I lower my max rate to 24 amp in the summer and max out in the winter.
This way it will use less cooling for battery....but still if there is hot day and it needs cooling it will cool still from 24 amp just fine.
Try to keep car outside in the shade if garage is hot in the summer days.
I keep it in my shop and it is always 76°F .
And if there is no other place but hot garage in the summer...try to keep hood open while charging...AC when kicks in it will easily reach over 150°F+ on 90 degrees weather and even higher if temperatures are in garage 100 .....
It will not hurt electronic but 12V battery will get life killed if going over 140°F most of the time in the summer.
This are my practice on Bolt and Tesla even in temperature controlled shop.
To see what really happened while AC kicks in when cooling HV DC battery install aftermarket temperature Guage with the sensor close to evaporate fan. And heat will be only much higher upstream where 12V battery is.
Keeping hood open while charging will also become habit and it will give you visual inspection on fluid levels and check for windshield fluid.
 

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It's normal. The battery management system will keep your battery in the proper temp range, especially as long as you're plugged in. You will hear "strange" noises coming from your car from time to time. Other EV brands do this as well.
 

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So, I have gotten my Juicebox running at it's max rating of 32 amps. According to the Juice Net web site it charges the car at 7.5 kW. (Typically 31.6 amps at 237 volts, assuming the Juicebox meters are correct.

The other night I was taking the dog out to her yard when I noticed a lot of noise coming from the Bolt. The Juicebox showed that it was still charging but the car said it was done. I pulled the power cable and the sounds stopped so I plugged it back in and shrugged it off.

Last night I again was taking the dog out and the Bolt was making noise, so this time I opened the hood. The A/C was running and the coolant loop for the power electronics was plugging away and the coolant was warm but not hot. While I was looking at things, it all stopped.

Now its a little warmer than it has been, it was about 90 when charging started and about 80 when I was checking it out. 7.5 kW is a lot of power to convert, so I can see the power electronics needing some cooling. But the A/C heat exchanger that cools the battery was active and quite cool. So was it needing to cool the battery? That doesn't seem right if the battery can charge at 50 kW that 7.5 would make it hot enough to need cooling.

Here is a chart of the charging session:

So, charging started at 6:00 and ran until about 9:50 at about 7.5 kW. Then it looks like the car stopped charging but continued to pull power until 10:15 or so. So for 25 minutes the car was pulling over 1.25 kW for dissipating heat from the charging. (The chart says that comes out to about 0.8 kWh, so not much financially.)

So here are the questions:

Is this expected?

Is the A/C running unexpected?

Should I lower the charge rate?

What do you guys think?
Hello. I have a 2020 with the same JuiceBox. That behavior is completely normal and expected. The compressor is shared with cabin and battery cooling, and battery cooling, if needed, usually occurs at the end of charging. In my experience the electronics coolant pump often runs without the compressor. With an OBD dongle and the Torque Pro app (android), you can see this and much more in greater detail.
 
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