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Blink end-of-charge demand curve, and power used by A/C

Posted: Sun May 22, 2011 9:55 pm
by GroundLoop
For anyone curious, this is a plot of power demanded by the Blink EVSE after a long charge.

After the charge was completed, I initiated the remote Climate Control, which likely ran the A/C for a short while. I was surprised at the amount of power consumed during Climate Control.

Image

Re: Blink end-of-charge demand curve, and power used by A/C

Posted: Sun May 22, 2011 9:58 pm
by AmarilloLeaf
I have found that if I have charged to 80%, then later request the climate control from CarWings, it sometimes (but not always) then charges to 100%.

Was your first charge an 80% or a 100% charge?

If it was 80%, I'd lay odds that all that juice was actually going to the battery, not the AC.

Re: Blink end-of-charge demand curve, and power used by A/C

Posted: Sun May 22, 2011 10:00 pm
by AmarilloLeaf
Great chart, BTW.

How did you get this data? Do you have a meter hooked up, or is this an easter egg in the Blink?

Re: Blink end-of-charge demand curve, and power used by A/C

Posted: Sun May 22, 2011 10:10 pm
by DaveinOlyWA
So its a 30 min trickle down charge time?

I would have thought it to be longer than that

Re: Blink end-of-charge demand curve, and power used by A/C

Posted: Sun May 22, 2011 10:14 pm
by GroundLoop
This was a 100% charge. (I've never used the 80% charge option.)

I've found that even with a recent 100% charge, reconnecting the Leaf & Blink will start a fresh charge cycle that consumes quite a bit of power before determining the battery is, again, fully charged. (This happens whenever the Blink hits Midnight on one of the All Day schedules, thanks to a bug.)

This data comes from the ANSI optical data port on SDG&E's GE utility meter.

I take this data to be 'absolute' in that it is, exactly, what I will see on my power bill.
The meter runs 1.4% higher (in kWh) than the number reported on the Blink Network Dashboard.

The duration of the 'trickle' consumption at the end seems to vary. I've seen cycles with none at all -- just a straight drop to zero at the end. I don't know what is responsible for this.
Image

Re: Blink end-of-charge demand curve, and power used by A/C

Posted: Tue May 24, 2011 8:08 am
by garygid
Can you show (with no climate control) the graph for:

1. a normal 80% charge, including at least two hours after the end-of-charge, looking for Equalization being done.

3. restart the 80% charge on an already 80%-full LEAF

3. charge to 100%, plus 2 hours, again watching for Equalization.

4. restrart a 100% charge on an already 100%-charged LEAF

5. start an 80% charge on an already 100% full LEAF

Thanks.

Will you please share exactly what hardware and software (and where obtained, model/version numbers, cost) you need/use to gather and graph this data?
I would like to try it.
PM if you do not want to post,
but I think many would be interested is this already-tested data-capture "package".

Re: Blink end-of-charge demand curve, and power used by A/C

Posted: Tue May 24, 2011 8:47 am
by Herm
so average about 1.2kw to cool down the car and then 0.4kw to keep it cool?.. I assume the car was in a garage.. what was the ambient temperature?

Its a full size AC, should be ok in full Texas heat.

I would love to know what the pack voltage is after that cell balancing session at the end.

Re: Blink end-of-charge demand curve, and power used by A/C

Posted: Tue May 24, 2011 8:49 am
by evnow
What I've seen is charges of about 0.05kwh after 80% (or 100%) charge completes - once or twice after a couple of hours. Do you also see that ? I've assumed this to be during cell balancing.

Also, the utility meter you are using is exclusively for Blink, right ?

Re: Blink end-of-charge demand curve, and power used by A/C

Posted: Tue May 24, 2011 8:55 am
by DaveinOlyWA
its too bad that we dont have the option to warm the cabin during winter when charging instead of just wasting the excess heat. wonder if its too late to make any "winter package" suggestions?

Re: Blink end-of-charge demand curve, and power used by A/C

Posted: Tue May 24, 2011 10:39 am
by Glenn
DaveinOlyWA wrote:its too bad that we dont have the option to warm the cabin during winter when charging instead of just wasting the excess heat. wonder if its too late to make any "winter package" suggestions?
Dave, I don't have my car yet, but I thought that the very thing you're asking for is already available in every LEAF, unless I'm not understanding what you mean by "wasting the excess heat."

Glenn