Ultimate Biplane horrible sqeel from Brushless motor
#1
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when I hit full revs on my AXI motor a loud screech comes from the moto/ESC area, I dont know what it is...the plane also loses 80% power too, all I have to do is back the throttle off a bit and it goes away. Im not sure if the motor is overloading the ESC or there is a problem with the motor!
I have included a video of it for yall to watch and tell me what you think.
Here is the video; http://www.youtube.com/watch?v=c43t2OI-HHY
I appreciate any help with this
Cheers
Jas
I have included a video of it for yall to watch and tell me what you think.
Here is the video; http://www.youtube.com/watch?v=c43t2OI-HHY
I appreciate any help with this
Cheers
Jas
#2
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Jas,
This problem is sometimes seen on brushless ESCs when the voltage is just a bit too high for maintaining a proper sync between the ESC and motor. Typically, it happens on a fully charged battery pack when the cell count is at the maximum rating of the ESC.
The simple fix is to use less full throttle at the start of your flight. After a minute or so, it should no longer happen at full throttle. The more complicated fix is to try a different ESC or lower your cell count and adjust the prop size accordingly.
Newer ESC designs like the Jeti Advance PLUS rarely exhibit this problem. On my older setups that occasionally show this sync issue, I have learned to take-off with less than full power and fly around the field once before going freestyle.
Good luck!
This problem is sometimes seen on brushless ESCs when the voltage is just a bit too high for maintaining a proper sync between the ESC and motor. Typically, it happens on a fully charged battery pack when the cell count is at the maximum rating of the ESC.
The simple fix is to use less full throttle at the start of your flight. After a minute or so, it should no longer happen at full throttle. The more complicated fix is to try a different ESC or lower your cell count and adjust the prop size accordingly.
Newer ESC designs like the Jeti Advance PLUS rarely exhibit this problem. On my older setups that occasionally show this sync issue, I have learned to take-off with less than full power and fly around the field once before going freestyle.
Good luck!
#3

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If your ESC has adjustable timing, you may want to try the lowest/most-retarded setting too. That has helped (but didn't quite cure) the problem in the past.
#4
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This is definitely a timing issue. The cause of the timing problem could be incorrect prop size or too much voltage. With some setups the voltage is so high with a fully charged pack that the ESC cannot time properly at full throttle. Too large of a prop can have the same effect. What motor, ESC, Prop and Battery are you running? Running it static like you are in the video is also bad. The setup will unload in the air by 10-15%. If it is an outrunner, the ESC needs to be set for a higher timing and the opposite for inrunners, considering the ESC is programmable.