Motor is hanging

[Kalle]

Hello together,
my name is Marco and iam building now since a year on my copter. Many times i got help by friendly people from the FPV Community Forum. But it looks like no one really has a idea about my newst problem. I hope maybe in this forum someone can give me a tip what the problem could be. Maybe you already recognized that my english isnt that good...i hope its still good enough to explain my problem.

I have builded a octocopter with the u8 135kv motors in combination with YGE 60HV ESC. As an fc iam using an AQ6.
The problem is that when iam flying the copter one motor (its always the same motor) is suddenly giving up and stops directly turning. It looks like he is hanging between two poles. If i go down with the throttle and and than high again everything is turning normaly again until suddenly its happening again. Na i see my english really sucks...em this video should explain the situation much better than my words.

https://www.youtube.com/watch?v=sL0fudvFKE0

I already tryed:
resolder on every joint
switching/replacing the ESC of and working motor with the one who is not working
replacing the motor
using a other port on the AQ6
calling the YEG company

and still always the same ARM of the copter is not working. It doesnt matter which motor is hanging on this arm the one who is there is giving up. Ah and i was checking every motor by making them on the trottle channel if they are working...they are...all of them are working perfect when iam making the directly on the channel.

I really hope one of you can help me anyway thanks for trying by reading this post

Marco

[bluuu]

It sounds like loosing sync on motor. Best way is replacing ESC and/or motor. It must be something with esc/motor, not FC.

EDIT:
are you sure this esc have the same parameters (timing) then other ?

EDIT2:

Can you tried esc and motors without FC, just plug to reciver ? Maybe esc setting are wrong for this motor/props combination.

[Kalle]

Hey thanks for the quick answere
i already tryed that i was pluging the esc directly on channel 1 (trottle) of the reciver. Its working without problems i can go as high with the trottle i want and the motor is working perfectly.
I can try to relearn the ESC but i thought if its working directly on the reciver that good it cant be a problem of the ESC but no iam not 100% sure with the timing i can recheck it. Could it be that i made something wrong with the calibration of the FC?

If the settings of the ESC are not perfect for this motor prob combination why the others are working? btw sometimes i have the same problem on a other arm (always the same so all in all 2 arms are showing this problem)but its really not often just sometimes and not reproducible.

[bn999]

Wow, what a machine. What does it weigh so far?

The ESC certainly sounds like it is loosing sync. If you have replaced (or exchanged) the motor and ESC and it is still happening, the only thing I can think of is that the output called for on that particular arm / motor is somehow different than the others. Perhaps you could record a log of a short flight showing the problem and post it here.

[Kalle]

Em the weight is something like 12 kilos i think the batterypackets are so heavy...
Ok i will post a logfile tomorrow
thank you very much ure giving hope

[chschmid]

Kalle

Did you say that you mounted a working mot/ESC on the "problem" arm?
My best guess is that you have a EMI problem with your signal wire of this motor.
When you run it from another PWM source (with different wiring) it works.

Try to move the ESC and wiring or use a shielded wire and give it another try.
I would even tie it down and try with "more throttle". Usually this EMI thing happens with high currents.

Cheers
Christof

[bn999]

Good point. Or, put some small amount of capacitance at the PWM input to the ESC at the ESC. Maybe 10nf.

[kinderkram]

I sent Marco here after we didn´t get it sorted out in the FPVC forum.

My first guess was 1 phase of the motor wire since it only happened on this motor.
He exchanged ESCs, changed the ports etc. always the same motor.
He even tried a servo tester on several motor/ESC combos - all were ok.

It´s unlikely the FC then all motors were in trouble. But if it was the ESC it should act the same on other motors.
And if it was the motor it should act the same on all ESCs.

That´s when I got lost...

[Kalle]

i have currents which are going on maximum 240 A with 12S (iam never reaching 240A the copter is going down befor i reach 70% of the throttel) and if its the EMI why just on this side of the motor? But its sounds not bad.. the idea i mean the problem sounds bad...
Edit: i habe this problem by flying as Octo (much higher current) and as Quadro (lower current than by octo)...how can it be that the other motors are working even the current is going so much higher by flying a octo flat
would it help if iam making a video of every step youre telling me to do?
thanks a lot for this massiv help

Edit: When i said i was switching the motor i just turned the motors on the problem arm. The working motor under the not working motor is now on the top and the not working motor under him the cabels are the same. What i wanna say is that the motor who was working is now on the top with the same cabels he had befor the cabels were not moved and now the working motor, who is on the top is not working. On my copter the 2 ESC for each arm are next to each other so i tryed switching the cable from the ESC to the motors and its still not working...i didnt switch the position of the ESC
What is a mot/ESC? All my ESC are working but i dont know what mot means?

[kinderkram]

Ok, now we´re talking.

mot means motor

So you didn´t swap motors with ESCs but only changed their places?
Then desolder the motor with troubles from its ESC and solder another motor to it.
If the problem still exists, then it`s the ESC.
If not, then solder the 1. motor to another ESC. If the problem still exists, then it`s the motor.
A bit of work but the best way to find out.

We obviously had some language problems - in German!