Time to solve the problem of the miter saw tripping the breaker every time I try to use it. Above is the inside of the handle with a suspicious empty spot in the upper left.
The switch controls the motor power (black, left) while the neutral is carried straight to the motor. The red and yellow wires on the right are also switched and ‘power’ the blade brake.
A Hitachi soft start module was installed in the open spot and wired in to the saw. It gets wired between the motor and the switch and has a separate connection to the neutral. It also has a potentiometer to adjust how soft you want the start to be.
My only mistake was cutting the power wire a little too short so the connector ended up being in the bottom left corner and couldn’t be completely tucked away. This $10 part lets me use this saw again, which I haven’t been able to use for many years.
I’m still not sure what exactly caused the problem. I used the saw a ton for the first few years after we moved in to the house, and no problems. Then it would trip the breaker when I tried to start it after using it once or twice. I replaced the breaker, and no change. I used a different, but still 15 amp miter saw, and it tripped the breaker. The new breaker, the 20 amp breaker (it was always a 20 amp breaker, with 12 gauge wire, so up to code). The saw is hard mounted, so I haven’t tried taking it to a different circuit.
As always, questions, comments, or weird electrical problems of your own are welcome!