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turbo2ltr
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Re: My findings on the CAN bus

Fri Feb 25, 2011 11:14 pm

I just charged to 80% for the first time. This charged to an SOC of 85.2. I thought for sure it would be closer to 80% than the carwings indicated 83%, not higher than 83%..
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garygid
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Re: My findings on the CAN bus

Fri Feb 25, 2011 11:30 pm

Perhaps display SOC (0 to 99.9) or SOC/4 (0 to 25.0) or kWh (00.0 to 24.0).

Then show 23.9 as 23:09 or some such?
See SOC/GID-Meter and CAN-Do Info
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turbo2ltr
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Re: My findings on the CAN bus

Fri Feb 25, 2011 11:41 pm

The problem is the hours only go up to 30 something, and the minutes only go up to 59. So theres no way to show a number like 67 no matter where you place it in the clock display..
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garygid
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Re: My findings on the CAN bus

Sat Feb 26, 2011 7:21 am

That is why I suggested showing SOC scaled as "kWh remaining", 0 to 24, instead percent (0 to 100).
See SOC/GID-Meter and CAN-Do Info
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wwhitney
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Re: My findings on the CAN bus

Sat Feb 26, 2011 7:51 am

turbo2ltr wrote:The problem is the hours only go up to 30 something, and the minutes only go up to 59. So theres no way to show a number like 67 no matter where you place it in the clock display..
You can encode two full digits: XY = X:0Y. I.e. 67 = 6:07.

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evnow
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Re: My findings on the CAN bus

Sat Feb 26, 2011 8:01 am

wwhitney wrote:
turbo2ltr wrote:The problem is the hours only go up to 30 something, and the minutes only go up to 59. So theres no way to show a number like 67 no matter where you place it in the clock display..
You can encode two full digits: XY = X:0Y. I.e. 67 = 6:07.

Wayne
Good suggestion.

Gary's idea of displaying kwh would also work ... but would involve some conversions.
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turbo2ltr
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Re: My findings on the CAN bus

Sat Feb 26, 2011 9:14 am

garygid wrote:That is why I suggested showing SOC scaled as "kWh remaining", 0 to 24, instead percent (0 to 100).
I don't know. Might as well just look at the SOC bars at that point as you are losing 75% of your resolution.
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wwhitney
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Re: My findings on the CAN bus

Sat Feb 26, 2011 11:38 am

turbo2ltr wrote:I don't know. Might as well just look at the SOC bars at that point as you are losing 75% of your resolution.
What is the underlying resolution of the CAN messages? Kwh to one decimal place is actually a finer resolution than SOC as an integral percentage. Either one would be plenty, I would think.

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turbo2ltr
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Re: My findings on the CAN bus

Sat Feb 26, 2011 11:44 am

less than 1.
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turbo2ltr
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Re: My findings on the CAN bus

Sat Feb 26, 2011 12:00 pm

I was going to say that you can't just convert SOC to capacity without taking into account the long term loss of capacity and without knowing what the BMS is/isn't correcting on it's own. But technically there is no guarantee I have found SOC and not capacity. It could be capacity remaining, meaning that it's not corrected for long term loss of capacity and full scale "100%" will dwindle over time. I can't think of any way to know the difference without simply seeing what happens over time. I suppose if it were capacity, battery temperature would effect the 100% value, but it's all unknown at this point. (Damn I need that giant refrigerator again)

What we do know is that this number I found is the basis of the range calculation. So one would think that as capacity drops, so does the range, therefore so must this number, which would seem to indicate that this is not SOC but capacity. But, that all depends on which module is compensating for loss of capacity. More tests!
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