393 motor controller not responding

Today I bought two new motor controllers, but one of them doesn’t work quite right. You See, I plug it into the motor and the 393, and when I try to run it, it runs fine one way, but it wont turn the other way. It just wont respond in that direction. I thought it was the motor originally, so I replaced the motor, and that motor didn’t work so I replaced the controller, and it worked fine. Whats up with that?

Inside the MC29 are four transistors and a PIC that controls them. The transistors are arranged in a configuration known as an H-Bridge that is able to control the polarity of the voltage on the two motor terminals. Only two of the transistors will be on for a given motor direction, sounds like one of them (or something else in the MC29) is damaged. Call VEX tech support and get them to replace it for you.

I might get them to repair it, but Im not sure if it would be worth it. I mean, if I were to send it to Vex tech, then get them to repair it and send it back, I don’t know how much it would cost and weather it would be worth it.

If it was a new MC29 call tech support and explain your issue, it should only cost you postage to send it back or perhaps they will have a better solution.

Our club had a MC29 controller caught on fire and we sent it back to IFI. They were very generous and send us 2 brand new ones back.

Not that they will do that again, but give them a call and see. Usually they will at least send you a new one as they keep the old one to identify the issue.