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Video of Firmware 4.5 pulling juice from wall, NOT battery.

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Here is video proof that when Firmware 4.5 is installed, cooling your car (or heating it,) will get it's power from the wall - NOT the battery.

http://www.youtube.com/watch?v=b4KuAMeN8ug

accharging.jpg
 
I guess technically it is coming from the wall into the charger, into the battery, and then right back out into the cars HVAC system. I don't think the HVAC is an AC (alternating current) system so it can't be running directly from the shore power. It might even take a trip through the 12V battery as well.
 
Yes, I doubt the car's systems are "dual voltage". Likely the car "sees" how much accessory power is being consumed from the battery and throttles the charging circuit up to the same amount to "make up" what is coming from the battery. From my TED graphs, the power does seem to match what is running. I believe when running the a/c and the sound system, my TED showed about 1 kW.
 
Yes, I doubt the car's systems are "dual voltage". Likely the car "sees" how much accessory power is being consumed from the battery and throttles the charging circuit up to the same amount to "make up" what is coming from the battery. From my TED graphs, the power does seem to match what is running. I believe when running the a/c and the sound system, my TED showed about 1 kW.

Yup. Just wait until the winter when you see the pre-heating requires 26A. :)
 
So if I schedule my car to charge at 7pm does this mean that once it reaches full charge it will continue to pull from shore power as needed to keep the full charge, or will it not come on again till the charging is scheduled at 7pm? This seems I important if you try to charge during off peak and kept the car plugged in.
 
So if I schedule my car to charge at 7pm does this mean that once it reaches full charge it will continue to pull from shore power as needed to keep the full charge, or will it not come on again till the charging is scheduled at 7pm? This seems I important if you try to charge during off peak and kept the car plugged in.

I wonder about that myself. What I do know is that shore power will be drawn for accessory use at any time (i.e. you open and get into the car while plugged in or turn on the HVAC via the mobile app while plugged in). I would hope that "top up" charging cycles would respect the TOU timer.
 
I wonder about that myself. What I do know is that shore power will be drawn for accessory use at any time (i.e. you open and get into the car while plugged in or turn on the HVAC via the mobile app while plugged in). I would hope that "top up" charging cycles would respect the TOU timer.

From my experience, "top up" charges occur every 24 hours or so based on the last charge, so it likely respects the timer in that way. Shore power is only turned on for on-demand use when pre-heating/cooling is requested. For example, open a door so that the radio turns in, it won't click the HPWC/UMC on.
 
For example, open a door so that the radio turns in, it won't click the HPWC/UMC on.

Mine definitely does click the UMC on and starts to draw power in this scenario. What I need to verify is whether the HVAC is on when I do this. I currently charge at a reduced power level, and also noticed on my graphs that when I went out to the car to get something, the power consumption jumped up from the baseline charging level for the minute or so I had the car's door opened.
 
I think someone mentioned it, but I want to confirm that shore power does not negate vampire loss.

So, i drove around today, had parked with 114 miles rated range. Plugged it in but did not charge, came back 4 hours later and my rated range is 112 miles.
That leads me to believe there is still vampire loss occurring and shore power is _NOT_ being used to fight the evil vampires.
Maybe I need to silver coat my charge socket - ow wait, that's done to fend off werewolves.
 
Hope this is not OT.

I just installed my HPWC and am still on 4.4.

This weekend was warm here so I turned the A/C on before I went out for the day.

I am sure it was pulling shore power as the HPWC LEDs were pulsing. This never happened just plugged into my 240V outlet.

I thought I read somewhere that 4.4 users were hit or miss with this.
 
This weekend was warm here so I turned the A/C on before I went out for the day.

I am sure it was pulling shore power as the HPWC LEDs were pulsing. This never happened just plugged into my 240V outlet.

I thought I read somewhere that 4.4 users were hit or miss with this.

I never saw shore power being drawn for anything other than charging prior to v4.5. Now, if I turn on the HVAC via the mobile app (or even just get into the car with it plugged in) I can see my UMC LEDs scrolling and I can see the power on my energy monitor in the house.
 
I've seen the same behavior on public charging stations too, with 4.5. I regularly use a Clipper Creek J1772 at the local Caltrain station. When I turn on the A/C as I approach the car, I can see the charging light wink into life on the wall unit. It's pretty neat.
 
Yes, I doubt the car's systems are "dual voltage". Likely the car "sees" how much accessory power is being consumed from the battery and throttles the charging circuit up to the same amount to "make up" what is coming from the battery. From my TED graphs, the power does seem to match what is running. I believe when running the a/c and the sound system, my TED showed about 1 kW.

I think it is more like this:

The UMC passes AC power to the the on board charger (or chargers), the charger rectifies to DC at ~384V, this 384V DC bus is connected BOTH to the battery and to the DC-DC converter, which drops the voltage down to the 12V bus, which feeds all the accessories. So while the charger is energized, it does not necessary have to pass DC to the battery (if there is an intervening contactor, as I believer there is), it can bypass the battery to supply "shore power" to the DC=DC convertor and thus more or less directly to the 12V accessories.

BTW, this is why the 12V battery will discharge if the main charger fails, since the main charger and DC-DC converter are intimately linked.