Prop not spinning

[Squiddley]

I have one prop on a Phantom 4 that when I start them up theres one that sometimes doesnt start up but just sits there kind of jerking like its slipping, was thinking its the motor giving issues, Ive turned it by hand and with the prop on and with the prop off seems smooth dont notice any difference from the other ones but yet sometimes it will start up normally and next time its sits there like its stripped, anyone have any other ideas as to why its doing this before I got out and spend money on a new motor.....the Bird is like new very few hous on it at all, kind of weird that the motor would be bad already, anyone have any ideas?

 

[Erised]

Motors are pretty dependable they usually have bearing fails before any windings' go. This could be the ESC or a bad solder to the ESC. Being intermittent makes it very hard to pin point, this could become a fall out of the sky situation, I would not take a chance and send it in for repair. If your unit is not on warranty you could open the shell and check the connections. ECM to ESC corrected.

 

[Squiddley]

Motors are pretty dependable they usually have bearing fails before any windings' go. This could be the ECM or a bad solder to the ECM. Being intermittent makes it very hard to pin point, this could become a fall out of the sky situation, I would not take a chance and send it in for repair. If your unit is not on warranty you could open the shell and check the connections.

thanks for the info it is not my drone it's a friend of mine I'm just helping him out trying to figure out the problem ...I think he's screwed for warranty because he nodded his controller with the intelite panel so warranty is probably out of the question will most likely take the shell off and have a look see if we can see anything ...I took it out today and it took 3 times starting and stopping it before the one prop acted up and wouldn't go, when it doesn't go it kind of screams like it's slipping that's what made me think maybe the motor

 

[With The Birds]

Motors are pretty dependable they usually have bearing fails before any windings' go. This could be the ECM or a bad solder to the ECM. Being intermittent makes it very hard to pin point, this could become a fall out of the sky situation, I would not take a chance and send it in for repair. If your unit is not on warranty you could open the shell and check the connections.

ECM? Control module? I would think the ESC to be a more likely suspect- it should throw an error code in DJI GO if that's the case.

 

[DanMan32]

Motors are three pole. Sounds like one winding isn't working where if the motor position is right, inertia keeps it spinning otherwise it gets stuck.
You can send in only the aircraft if the issue is not dependent on the controller which for this issue it is not.

 

[With The Birds]

Motors are three pole. Sounds like one winding isn't working where if the motor position is right, inertia keeps it spinning otherwise it gets stuck.
You can send in only the aircraft if the issue is not dependent on the controller which for this issue it is not.

The motors are three phase, can't be three poles (poles must be even number).

 

[DanMan32]

Technically yes but 3 phase motors usually refers to a different motor type than syncronus brushless motors.
And actually, the windings share poles as you are terming poles. Think of a triangle. Has 3 sides, two ends on each side but one end of one side is common with another side.
So it still can be considered 3 pole. Only one pole activated at any one time.
The rotor would have to have even # of magnetic poles since they are permanent rather than electromagnetic.

 

[With The Birds]

Technically yes but 3 phase motors usually refers to a different motor type than syncronus brushless motors.
And actually, the windings share poles as you are terming poles. Think of a triangle. Has 3 sides, two ends on each side but one end of one side is common with another side.
So it still can be considered 3 pole. Only one pole activated at any one time.
The rotor would have to have even # of magnetic poles since they are permanent rather than electromagnetic.

The motors are a synchronous AC motor with 12 poles on the stator (12 Coils) and 12 permanent magnets (6 pole pairs). The ESC provide a true 3 phase AC drive (sine wave) to the motor. Motor speed is directly locked to line frequency as is the case for any true AC induction motor. 3 pole motors do not exist and a motor could not run with only one pole energised.

 

[alokbhargava]

ESC may not generate error on light load conditions unless there is a short circuit. This seems to be a good sign. Either the motor rotor is miss aligned or it's not getting correct voltages.

If you are sure, motor was not hit during flights, better send ONLY aircraft to dji service. No need to send RC controller.

 

[Squiddley]

okay Thanks ya Im thinking he might just send it in for repair because I believe he still has warranty on it, what is the warranty on the P4's 1 year? better to send if theres warranty then to start tearing it appart

 

[Erised]

ECM? Control module? I would think the ESC to be a more likely suspect- it should throw an error code in DJI GO if that's the case.

Your right ESC. I have been working with Cummins ECM's in the last few days and I guess I got brain stamped.