I want to use the 393 2-Wire Motor for a Science Olympiad competition, but one of the rules is that there can be no integrated circuits. I was very surprised (and a little sad) to discover open opening it up that there was an integrated circuit attached directly to the back of the motor (http://www.vexrobotics.com/wiki/File:Vex_393_DC_Motor.jpg). So since this motor is obviously a standard hobby motor would it be possible to rip the integrated circuit off and attach the motor directly to a battery?
EDIT: What is that raised disk on the back of the motor/circuit board? Is it safe to take off? The motors I’ve been working with didn’t have anything like that.
Hi Captjack,
We’re glad to hear that you’re finding new innovative ways to use VEX hardware. Lucky for you, there are no integrated circuits (ICs) on the back of the 393 motor. What is on the back of the 393 motor is called a Printed Circuit Board (PCB). ICs are almost always used with PCBs so they are frequently mistaken for each other. A PCB is an arrangement of copper and fiberglass that allows electrical components to be cheaply and easily connected to one another without using any wires.
Your hunch is correct, you can remove the PCB with no direct ill effects to the motor. HOWEVER, be warned that this opens up your motor to potential permanent damage due to overheating since the PCB includes a thermal breaker to protect the motor from overheating. Also, be advised that the PCB contains capacitors that reduce the amount of electrical “noise” generated by the motor and sent to the motor controller. Since the capacitors will be removed with the PCB, it is highly recommended that you never power the modified motor with a Cortex or Motor Controller 29.
If you decide to modify your motor and compete/ever plan to compete in the VEX Robotics Competition, I highly recommend that you clearly mark the outside of the motor case so that the modified motor does not accidentally get used on a competition robot.
The disk in the center of the PCB is the “back” of the motor.
Let me know if you have any more questions,
Charles
