John,
Would you send me a few of the motors that fail to start up and cause the 3 blinks? I have yet to see one fail in the lab to run some tests to find out why this happens.
The system looks for back-EMF to determine if the motor is running. If no back-EMF, then it shuts-down, thinking the motor is stalled. I have motors here that have worked since I designed the electronics, 4 years ago, and my testing indicates a variety of motors work well without failing.
While does not seem to be a high failure item, but is annoying and something is going on, so a few motors may allow me to determine root cause of the issue.
I'd be glad to Jon, I don't really have any use for them. I'd love to know why they're getting flagged as failures, several I've tested seem to be perfectly fine. I'll pack a few up and ship them out.
Would you email me an address where you'd like them shipped?
John,
Received the 4 motors today, thank you. All 4 motors were bad. The torque is way low per spec, and when connected to the electronics to PWM the motors, they would not even spin. I do not know why these motors failed, but will try and determine what happened to them.