PX4 w/ PM07 Current Limiting Issue on Octo+ Configuration

#1

When performing individual “thruster” testing, each thruster was drawing ~18amps off of an 11.1V battery at max speed. When I assembled 8x of the thrusters into an Octo+ configuration with the setup below, at max throttle, my current reader displayed a max discharge of 800.5w (.5 probably for the controller) or roughly limited to 100w per thruster.

Given that the PMB (PM07) has a total 120A output max, I was wondering if there is a way to increase the output threshold in the QGroundControl software? I assume that is in the power setup, but I’m not sure what to change. Alternatively, is this an ESC programming or Power Management Board issue?

SETUP
-Radio: Spektrum DX8 with only DSM receiver plugged in right now
-PX4
-Octo+
-Power Management Board (PM07)
-Holybro Tekko32 F3 35A ESC BLHeli_32 3-6S
-Two 1300mAh TATTU Lipo Batteries connected in parallel with each battery having a 75C discharge rate

#2

The power setup that you are looking at is just for the battery percentage estimation. By providing the “amps” you calibrate how much energy a full battery contains and therefore you can estimate the charge based on how much current you have “used”.

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#3

Any thoughts on what I can change to get past what seems to be an 800W current limit (100W/Motor)? I know that the hardware is capable of more, but am currently at a loss where I can address this on the software side.

#4

Have you done the ESC calibration to make sure you can use the full range with the PWM signals?

#5

I ended up using a 14.8V battery instead of a 11.1V battery and that solved the problem. Though a 11.1V was sufficient when I was testing a single thruster, it was not sufficient for a octocoptor. Thanks for the help!

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