ESC calibrations

Hi all
I moved from 4s to 6s on ma hexacopter. I use 40A Hobbywing XRotor.
I perform esc calibration but copter flips on first flight - after take off I try to land but copter didn’t respond for throttle.
I suspect problem with esc recalibration for 6s lips .
Can anyone help me with the log analysis?
log_49_2018-6-2-20-17-20.bin (732 KB)

No reason to recalibrate the ESCs.That calibration is all about signals from the RX and PWM output fromt the FC with nothing to do with voltage.The ESCs will detect the voltage themselves and give out beeps to signify the voltage being used.

You had no throttle authority because you were in Loiter which has an extreme choke on the throttle.You want to be in Stabilize to get it up and hovering and then autotune it for the extra power you just stuffed under the hood (a 50% increase ).

Maybe worth reverting to stock loadout PIDs before an autotune too ( I never shirk flashing firmware again after a problem ).There will be a lot of difference from the tune you had and maybe that won’t help initial take off tests.

Thx Jagger.
It’s strange because I landed in Loiter mode and there was no problem (before I changed lipo to 6s) …This time during land hexa jumped several time and flipped…I perform autotune but with 4s lipo
maybe the problem is propeller ?- I use the same apc 1447 with max mt3515 motors

One more thing
ESC beeps after power on and try to spin two motors. After arm everything is ok. The same situation was with 4s lipo so I did not care.

Landing in Loiter with a well tuned copter is easy.As is take off.But it’s pretty useless if the tune isn’t right,and it won’t be on 6S.I use loiter to descend for landing from far away and I floor the throttle from 400 feet and slide it in using pitch.Absolute zero throttle for several minutes,except it doesn’t go to zero.Try that in Stabilize and you’ll be picking up the wreckage.The two modes handle throttle so differently but Stabilize is the one that gives you control.Loiter takes control away from you.Makes it easier to fly but impossible to control it fast if you need to.Which is why there are flight mode switches.Stabilize has saved me many times where an automatic mode would not have.

As long as the motors are rated for those props at that voltage it’s no problem.

ESCs beeping and twitching is because they are not receiving the output from the FC,maybe because the safety switch isn’t engaged ? Or because they aren’t calibrated correctly and they aren’t getting the correct PWM values.

I’d reflash the firmware and start over from scratch doing a full set of calibrations.Transferring settings from one copter to another (which your’s essentially is with the power increase) is fraught with danger.

Thx Jagger
Do You know where I can try to change PWM values for ESC.?
I searched full parameter list but I’m not sure.

That’s a calibration rather than a parameter write.An ESC calibration is pretty painless nowadays on a Pixhawk.There’s even a tab for it in mandatory hardware in the initial install page.That’s where you teach the ESCs the range of your radio throttle.You should only need to do it once.It’s how I usually shut noisy beepers up but it could be a dodgy wiring connection or config fault (didn’t notice anything in the log).

I use the Hobbywing 40A ESCs extensively and they always take a calibration first time unless I’ve missed something in the set up.At least their beeping is one of the least offensive offerings out there.:slightly_smiling_face:

Try the ESC calibration in Mission Planner and see if it shuts them up.

Thx Jagger
I will try the ESC calibration in Mission Planner.
So far I’ve done it all at once following the instruction
if it can cause differences in behavior ESC ?

That should have done it,and is the same as using the tab in Mission Planner to be honest.The ESCs will beep until the safety switch is pressed.So give it another go and see if it shuts them up.If not we’ll have to look for another reason.