I was wondering, if I wanted to check my ESC output voltage , which terminals would I use (A,B,or C)? Also , I was wondering if I wanted to test my brushless motor with a power supply , which terminals would I use?

Sorry, but it sounds like you don't really understand how brushless motors work, in comparison to brushed.

A, B, and C are basically the same, they just have voltage at different times per each revolution of the motor (according to rotor position).

Also you cannot test a brushless motor with just a power supply. That only works for brushed motors. A simple DC source will not run a brushless motor.

A brushless motor is almost like a 3-phase alternator motor.
3 coils acivated one by one to build up a rotating magnetic field to rotate a rotor with a magnet. The only difference between a BL and a normal 3 phase motor is that with BL the coils and/or sensors are used to give feedback to the ESC so the can follow the rotations at any time.

To measure the voltage on the motor you can make a 3-phase diode bridge.

And yes, BL motors will not work when directly connected to a DC power source, that will only pull and hold the rotor into one position and burn the coils.

Thanks guys, DirkW has the correct answer, "I just don't understand how a brushless motor works". But now, I do have a little better understanding.

Hi,

If you want to test a brushless motor. Take a look here:

http://www.rctech.net/forum/radio-el...r-checker.html

MiCk B. :-)

Good suggestion MiCk B , I guess I would use the speed controller out of the car I'm testing and that's OK , however my question was more towards trouble shooting a problem in order to isolate it to the motor or ESC.

I've found the motor checker good to check a motor you are unsure of.

Better to put the motor on a checker, make sure it is ok, amp draw / timing etc. Then to damage a speedo with a dud motor.

MiCk B. :-)