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HPWC for SR+

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As an SR+ owner limited to 32A, I was wondering if adding an HPWC for charging would keep the battery charging at the full 32A AND supply extra current to run the climate.

This is really just a question to satisfy curiosity, I’m more than happy using my NEMA 14-50 UMC.
 
Do you have a Sr+? They are limited to 32A about 7.5-8kw. LR is limited to 48A about 11-12kw.

He has an X :), Gen 2 UMC is limited to 32A(40A).

To answer OP's question: Can you charge at 32A(40A) while providing preheating at 7-8kW if the supply is available?

My answers:

1. If charging from UMC with 32A(40A) limit > Not possible.

2. If plugged into a 40A(50A) or more HPWC > Maybe? since the power is available to power the onboard charger and preheaters. Vawlkus' response is one data point that shows it is possible.

3. RE: #2, If the supply source and wires can handle the load, I don't see why not.
 
2. If plugged into a 40A(50A) or more HPWC > Maybe? since the power is available to power the onboard charger and preheaters. Vawlkus' response is one data point that shows it is possible.

3. RE: #2, If the supply source and wires can handle the load, I don't see why not.

The car converts AC to DC. All the systems involved as far as I know run on DC. The AC to DC converter is 32A 240V on SR/SR+. So I don't see how it's going to provide more power, unless the preheating can run off extra AC power in parallel (edit: which I'm almost sure it can't).
 
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The car converts AC to DC. All the systems involved as far as I know run on DC. The AC to DC converter is 32A 240V on SR/SR+. So I don't see how it's going to provide more power, unless the preheating can run off extra AC power in parallel (edit: which I'm almost sure it can't).

That depends. AC > DC rectifier circuits are just four diodes. The onboard charger = one circuit. Heaters maybe another? Total guess here.

Only one way to find out. Limit your charge rate to 32A, connect to 40A(50A) HPWC, run the preheating, and see what the charge rate is.
 
That depends. AC > DC rectifier circuits are just four diodes. The onboard charger = one circuit. Heaters maybe another? Total guess here.

Only one way to find out. Limit your charge rate to 32A, connect to 40A(50A) HPWC, run the preheating, and see what the charge rate is.

I haven't really looked into it. But I'd assume it's AC->DC and then that DC feeds both the battery and any load from the car, either charging only, charging and running any loads or discharging (though slower) and running any loads.

Also setting the amps low and checking if it goes over might be unlikely to work though, even if it would be otherwise possible. Because one reason to reduce the amps is because you know the plug won't take the load and the breaker might trip. It would be bad if you set it low and then it pulled more amps just because of preheating or other drain.
 
The question was would there be extra power for the heaters if he swapped from the UMC to the HPWC, and there would be, regardless of if the battery charger system can make use of it.

How? The AC to DC converter is 32 Amps on his car. That's the limit of how much can come from the wall into the car (battery or otherwise). Obviously the battery can take 170kW supercharging so the limit is not the battery but the charging circuit/AC/DC converter.
 
How? The AC to DC converter is 32 Amps on his car. That's the limit of how much can come from the wall into the car (battery or otherwise). Obviously the battery can take 170kW supercharging so the limit is not the battery but the charging circuit/AC/DC converter.
That I don’t know, at a guess it’s adding load without diverting power charging the battery.
 
Yes that would be a possibility, if those systems could run on AC (as I mentioned). However as far as I know, everything in the car is either running off 12V DC or high voltage (300-400V) DC.
This is the right answer. @Vawlkus there's no way to draw more from a Level 2 charger than your onboard charger can convert to DC. If you are supercharging, it's a different story, but that has nothing to do with HPWC or Level 2 charging generally.
 
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The question was would there be extra power for the heaters if he swapped from the UMC to the HPWC, and there would be, regardless of if the battery charger system can make use of it.
Erm... the 32amp Sr+ on-board ‘charger’ is not on its own technically a ‘battery charger system’ technically it’s a 32amp capacity ac to dc device. Then on the dc side it is hooked up to all the DC loads. Which includes battery and heaters.
So No. You will not get 32amp charging to battery PLUS (x) amps to HVAC system ON A SR+.
 
Erm... the 32amp Sr+ on-board ‘charger’ is not on its own technically a ‘battery charger system’ technically it’s a 32amp capacity ac to dc device. Then on the dc side it is hooked up to all the DC loads. Which includes battery and heaters.
So No. You will not get 32amp charging to battery PLUS (x) amps to HVAC system ON A SR+.
Then they changed architecture from the S and X then, because my X has done that. *shrug*
 
The umc is limited at 32A right? That's the gate keeper. HPWC at a higher setting with higher current limit may be able to support 32A SR+ onboard charger plus heating element loads.

Who wants to run some tests =P?

yes the umc is limited to 32amp. ON THE SR+ the on board ac/dc converter ALSO HAPPENS to be limited to 32 amps. Put an Sr+ on a hpwc and you haven’t changed the on board converter so you are still limited to 32amps including heating.
Case closed.