Would appreciate strategy help for diagnosing PX4-battery issue

Pixhawk
1

Hi all-

After a few days of sifting through forum posts etc. trying to claw my way up the steep PX4/QGC learning curve, I think it’s time to ask for some help. I have a PX4 + PM07 on my quadcopter (stripped-down Parallax Elev-8) and I have been unable to configure the Power. Here’s some particulars:

  1. QGC reports a pretty close value for the actual voltage of my 3S battery. (resulting in a display of ~95% full battery.)

  2. When I try to calibrate, I get a ‘Dangerously low battery!’ warning, followed by ‘System does not support shutdown.’ This does not seem to match with #1, but I haven’t been able to figure out how to convince the PX4 that the battery is in fact charged.

It seems as though the power calibration is the way to get at this, but as I said I cannot get this step completed. By the way, the number of cells and full/empty voltage per cell seem OK, and the Amps per volt is 36. (The quad draws about 0.05 A in standby.)

Here’s what the battery status looks like:

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Couple of weird things in here: one, I don’t have 17 batteries. (I’m sure that’s counting something else!) two, there seem to be a lot of entries missing compared to examples I’ve found online.

Any pointers to other clues I need to gather would be much appreciated!

thanks,
Patrick

2

OK, here’s a more specific question: if this is the case

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given the numbers in my battery status message, why would I be hearing “batteries dangerously low” warnings at all?

Patrick

3

So…no suggestions? I don’t know what other information would be most helpful in getting me pointed in the right direction, but I’d be happy to conduct whatever tests might be useful. I can’t be the only one to have been unable to get past the Power calibration!

tnx,
Patrick