Todd writes –
In this blog posting I’m attempting to diagnose a problem with a motor power supply for a small metal lathe. I will document how I evaluate a circuit board and repair it if possible. I’m confident the problem is with the power supply because when I plugged in the lathe nothing happened. The motor doesn’t flinch even when the speed control is turned to high. Plus there is no voltage at all across the motor terminals so that does make sense. Something in the motors power supply is preventing power getting to the motor terminals.