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DeveloperPermalink Reply by jasonshort on August 10, 2012 at 5:12pm

Have you calibrated your ESCs before and can you recognize the beeping sequence? I'd also swap the bad motor with a know good one to be sure nothing is physically wrong. That and recheck all you cables.

Also, can you try the CLI motor test that spins each motor? 

Jason

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Permalink Reply by Richard Boyhan on August 10, 2012 at 6:16pm

Hi Jason,

I have calibrated successfully before.

Not sure how to swap a motor, I'm guessing I'd have to unsolder and re-solder?  My Quad came mostly assembled.

The cables look good.

When I power on, all the motors do there little chirping and I end up with motor number 4 doing a soft quiet chirp.

I've tried rebinding my transmitter, but that did not help.

I looked into the CLI and testing, but which test would I use to test spin each motor?

test] ?
Commands:
  pwm
  radio
  gps
  ins
  battery
  tune
  relay
  wp
  altitude
  sonar
  compass
  optflow
  eedump
  logging

Thanks for the help.

Richard

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Permalink Reply by Richard Boyhan on August 11, 2012 at 9:40am

I went ahead and partially disassembled my Quad and I found that the power distribution board connectors can be removed and moved around.  (Very Cool)  I'm not sure if I'm working with either motor 4 or 3, since after looking at the pin outs from APM2 it looks like I've been flying backwards all the time.  (not really an issue, just funny)  Anyway I moved the wires from my problem motor and the problem remained.  This tells me that my problem is either in the ESC or the motor or the wiring that connects the motor and ESC.  I plugged everything back the way it ways and I still have the issue with the one motor.  I tried recalibrating and all I get is a soft quiet chirp from the problem motor.  Anyone have any ideas on what might be the problem?

Thanks

Richard

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Permalink Reply by Richard Boyhan on August 18, 2012 at 3:25pm

I ended up purchasing a motor and ESC.  Replacing the ESC fixed it.  Now the question is, how does an ESC go bad and is there a way to test them, other then buying and replacing them? 

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Permalink Reply by Vernon Barry on August 18, 2012 at 4:58pm

I tried recalibrating and all I get is a soft quiet chirp from the problem motor

There is the answer, the ESC is likely working and either the bullet conenctors or motor wiring has an open circuit on one of the three phases. If you swap motors, I bet you find the ESC is good.

is there a way to test them

Manual calibration using the same RC transmitter and receiver you use with the machine following the directions on the wiki would let you know if it worked. The other process of following the ESC's manual and it's troubleshooting guide.

We use off the shelf RC equipment, thus you have to follow the manual for that piece of equipment. That said, the ESC is designed to be plugged into the throttle channel of the receiver. If it doesn't work there, it's not going to work with the APM.

how does an ESC go bad

Static discharge, broken wires, bad solder joints, reverse voltage, overloading or shorting the BEC which also supplies 5 volts to make the APM work internally. Being the signal cable is easy to reverse on the 3 pins, user error is typically the root cause. The key to keep in mind is it's a 3 phase motor. If you don't have all 3 phases hooked up, it will never work correctly.

Motors go bad for similiar reasons, shorts, opens from broken wires or solder joints. They have no electronics so at least they don't get killed by static. It's darn hard to hook up a 3 phase brushless wrong any wire combination to the ESC would make it spin. Combinations that make it not work are just disconnect any 1 of the 3 wires.

Basic electrical trouble shooting with a multimeter goes a long way. Motors are just coils of wire so you Ohm them out checking for shorts to the metal housing or opens where the coils should be connected to each other. Once you know the motor is good, then start with the ESC. I say this because most problems are the with the motoror or the bullet connectors. ESC usually let the smoke out when they go bad.

Also, understanding how brushless motors are built goes a long way for troubleshooting http://www.gobrushless.com/GBL_single_v2.pdf

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