Brownout during ESC calibration?

#1

I’ll start with, I fried some stuff early on. Totally my fault, I had connected an ESC backwards. I’m using the spark-o-lator inline now.

I think I fixed the ESCs and tested continuity on motors (all beeping on all 3 barrel contacts when I test). I think all good, and all four corners beep when drone is powered up.

Doing the ESC calibration;
Turn all dials and zero out remote.
Turn on remote.
Max throttle.
No usb connected to pixhawk; power up drone with battery.
Wait a few sec.
Arm it;; button goes solid red.
Power down; power up.
Wait a few sec.
Arm again to solid red. Hear brown tone.
Lower throttle.
Hear some confirming type sounds.
Turn up throttle to test
all motors begin spinning as per throttle for about one second and then stall out to zero, and remote starts beeping like it lost connection. Sometimes the lights on the pixhawk get dim and it starts acting weird.
I turn off and on remote, it reconnects but drone doesn’t respond.

If it is a brownout, it’s probably the power to the pixhawk, right?

#2

I have a very similar problem. I follow the same steps that @phunxin mentioned. At the last step (Turn up throttle to test), if I just turn the throttle up slightly (say 10-20% power), the motors spin indefinitely at low speed. I can leave the throttle at low power level for minutes and the motors keep spinning. The problem occurs when I throttle up to higher power. As @phunxin described, the motors stop, the transmitter indicates loss of connection and the pixhawk lights flash dimly. I have to disconnect the battery to clear this state.

I get the same results with fmuv3 and Pixhawk1 firmware. I’m using the latest Copter V4.1.3 OFFICIAL firmware.

Any ideas what we can do to diagnose this?

Thanks very much!

#3

Try the Mission Planner calibration instead and see what happens:

image

#4

Thanks @jax200. I am able to calibrate the ESCs through Mission Planner by following the instructions in the screenshot. The motors make the expected sounds during calibration. I don’t know how to test the motors after that calibration because I am not able to arm the drone (separate issue - I’ll create a separate post for that). Raising the throttle after calibrating outside of Mission Planner is the only way I am able to actually get the motors to spin. I suspect if I could arm the drone and spin the motors after Mission Planner ESC calibration, I would also get the behavior described in this post, but I don’t know that for sure.

I bit of addition info… the connection between my battery and the pixhawk is:

battery -> XT-60 smoke stopper -> power module -> pixhawk

#5

Try the Mission Planner Motor Test (SETUP/Optional Hardware). Adjust the throttle and duration as needed. First try motor A, then in Sequence -
image

You can remove the smoke stopper once you know it’s ok, ie, no smoke.

#6

Thanks again. The motor test worked reasonably well. Motors A, B and C spun as expected at 5%. I had to increase power to 7% to get motor D to spin.

I removed the smoke stopper and I am now able to increase throttle to 100% after calibration. Put smoke stopper back in, and the original problem described by @phunxin occurred again. Removed smoke stopper, recalibrated and took throttle to 100% with no problem.

@jax200, thanks again. Your input was very helpful.

@phunxin, it will be interesting to know if you are using the smoke stopper, and if removing the smoke stopper solves your problem.

#7

The smoke stopper is not intended to be left on, just for initial wiring verification. Put it back on whenever you make wiring changes to ensure you don’t fry something.

#8

It was the smoke stopper. Thanks everyone. I’ll never make that mistake again.

Everything worked except one motor after ESC calibration; Replaced the motor, the old one still had continuity as did the new one. The new one didn’t work. I rubbed the barrel connectors around to make sure I had a good connection, and tested the PDB to ensure it had voltage across the terminals before the ESC. I’m pretty sure it’s the ESC.

SOLVED The brownouts were the smoke-stopper.