Flight Log BAT.Curr Tot BAT. ENRG Tot explanation

ArduCopter
1

Good Morning,
Can someone please explain what BAT.ENRG and BAT.Cur Tot mean.
For example, I plot Curr Tot and it peaks at 10,000. i.e. 10,000 what units?
Likewise, when plotting Enrg Tot it peeks at 483. again 483 what units?

Also please explain the correct syntax for these variables is it BAT.Enrg.tot or BAT.EnrgTot or something compleatly different.
Thank you

2

mA.h

W.h

The units are presented on the bottom right side of the screen when you mouse over the data field AFAIK

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3

Thank you , I can’t believe I missed that. THANK YOU

Now I am confused. How is Ardupilot calculating these values?
The values I am getting in my logs make no sense.
This Aircraft has 2x 30,000 mAh in parallel and the battery was at 20% when landing.
Therefor I would expect something like 24Ah ish per battery whereas the log
BAT 1 27395.83
BAT 0 9739.583
I presume then is mAh not Ah
Still Battery 1 looks ok but bat 0 can’t be 9739.583

https://drive.google.com/file/d/1CEXvkhE4Jz0v16QH3BAigQV_L2RnyPQM/view?usp=sharing

4

There can be quite large bias when using the standard power modules if one is used as BEC and the other isn’t supplying any current.

5

Remove the access requirement for your log.

I think @LupusTheCanine’s answer is likely what you’re seeing, depending on how your monitors are wired and configured.

Unless you have accurate per-battery current monitoring, you may need to increase the BATT_CAPACITY to 60000 for a more accurate representation of parallel capacity remaining.

6

Thank you for your replies. The Battery monitoring is a full BMS i am developing.
The current and voltage has been rigorously tested and is correct.
This is a DroneCAN BMS. The current sensor are at the very beginning of the pack so all consuming current is measured including the BMS electronics.
There are two battery packs 12s 30,000 mAh each have there own separate BMS.
Node 42 and node 43.

I think I have sorted the log file access: -
https://drive.google.com/file/d/1CEXvkhE4Jz0v16QH3BAigQV_L2RnyPQM/view?usp=sharing

This is why I am very keen to sort this out as I am stll testing the BMS system.

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