Pixhawk4 with PDB and OneShot125

Hello Guys,

I need some help on this topic:

I have an Pixhawk4 (Holybro Link with the included power distribution board.)
Motor: Turnigy D2830-11 1000kvl
ESC: Multistar 32bit 30A-0-LITE

If I connect the ESC directly to the receiver I got it to work, but when I connect it to the power distribution board of the pixhawk it either constantly beeps or does nothing.

Any tipps on wireing and software to get it working? (I tried changing PWM_Ratings but sowhow it seems not to work)

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The constant beeping means its not getting a command signal. Make sure both the signal and ground connections to the ESC are connected.

I have connected both to the FMU OUT on the PDB (violet arrow)

You need to connect the signal wires to the small circular pads next to the power pads for each motor.

And where do I connect the Signal Ground?

You can connect it to any ground pin, they are all connected. Although, inside the ESC the main ground and the signal ground will be connected so the additional ground in the JST connector is usually redundant.

Ok I did that and connected the I/O PWM OUT from the Pixhawk to the I/O PWM IN on the Power Board. So my connections should be correct now right?

Can you send me what settings you use in the software?

Sorry I missed this earlier. You will need to connect the FMU PWM line as well. I’m not sure what settings you’re referring to - Once you’ve used QGC to tell it the basic configuration, set up your radio channels including an arm switch, and then calibrate the ESCs. After that the motors should work. When you switch it on you should get the happy sound, then you need to press the safety switch on the GPS unit until it double-flashes, then you should be able to arm it.

I am stuck when calibrating the ESC. If I follow the instructions the motors should spin when calibrating but they don’t move. I also tried connecting to the corresponding motor pinouts but no change there.

I mean the parameters like MAX_PWM and so on, what would you change there?

Motors don’t move during calibration except for a few twitches perhaps.

The esc ground pin wr exactly i have to connect,
Whether i have to connect it to FMU-PWM out
Or main GND of power management board

It doesn’t really matter where on the PMB you attach it - all of the grounds on the PMB are connected together. I used the main ground, but I had a separate power harness so it was an easy choice. Any of the PWM ground pins, or main grounds, or the CAP & ADC ground pins.

Will u suggest me where exactly i have to connect led lights to power management board.
I am using leds as shown below

The only source for 5V is on the ADC pins.