Detent torque

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I've noticed that the detent torque of the one of my P4P's motors is noticeably less than the other three motors. Just to be clear, detent torque or cogging torque is the resistance the motor has to being turned with power off as the rotor magnets interact with the stator and is felt as a kind of notch as you rotate the motor. Anyway, I was just playing with it and turned all four motors and found that the front right one is noticeably less notchy than the other ones. I'm not sure why this is so but it gives me some concern about the motor though I have 6 flights on it without a problem. Anyone else seen this and has anyone had a problem because of it?


Brian
 
I just checked mine and all four motors are a bit different, and I guess you could say that the difference between the strongest and weakest one is noticeable. Personally I wouldn't worry about it, motor failures are so exceedingly rare that there are probably many better things to needlessly obsess about :)
 
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One of my motors also has less detent torque, 600 miles later it's still flys' like champ.
 
One of my motors also has less detent torque, 600 miles later it's still flys' like champ.

You have 600 miles on your P4P -- that's got to be nearly 50 flight hours and 150 batteries give or take. I have a total of 121 miles on both my P4P and Inspire 1 Pro in just over a year.

But, if you have a motor with noticeably less detent torque and have managed 600 miles on it then that would definitely reduce my concern.


Brian
 
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Fly your drone for 5-10 minutes and then check the motor temperatures. If all show almost equal, no worries then.

Sometimes being too techie puts us into unwanted concerns


Sent from my iPhone using PhantomPilots
 
Fly your drone for 5-10 minutes and then check the motor temperatures. If all show almost equal, no worries then.

Sometimes being too techie puts us into unwanted concerns


Sent from my iPhone using PhantomPilots

That sounds like a reasonable test. Hopefully I'll get a chance to do just that in the next few days before I head out for a longer trip in mid February.


Brian
 
You have 600 miles on your P4P -- that's got to be nearly 50 flight hours and 150 batteries give or take. I have a total of 121 miles on both my P4P and Inspire 1 Pro in just over a year.

But, if you have a motor with noticeably less detent torque and have managed 600 miles on it then that would definitely reduce my concern.


Brian
It's my P4, got it last end of April, I would have more fly time but the weather has not been too good around here. I also have 4 batteries so it's easy to get 150,000 feet in one outing. My top distance travelled is 43,256 feet and many of my flights are high 20,000's and mid 30,000's. I live out in the country.
 
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+1. There is no worry here.

These are mass produced Chinese motors and there will be manufacturing differences.

Aside from trauma causing physical damage, the ESC will be first to 'report' if there is an issue with the driving of the motor(s).
 
When was the last time anyone experienced a hard motor failure with a P4 or P4P? Has it ever happened?
 
Perform a simple hover test flight (indoors if possible), or just energize them and let them spin for a while on the ground (no load). Then pull the FC log (.DAT file) with Assistant 2 and parse it with DatCon

CsvView/DatCon

Logged motor parameters are quite detailed. IIf there are any major abnormalities in performance with one of your motors you should be able to see it in the data.

Sent from my Pixel XL using PhantomPilots mobile app
 
When was the last time anyone experienced a hard motor failure with a P4 or P4P? Has it ever happened?
The bearings are the only wearing part(s)
 

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