Help with the wiring for my VDrum sander

[Marc Ward]

I bought a 1/3 horse 1725 rpm motor for my Stockroom Supply Vdrum sander project. It is all done. Now, I am trying to wire a switch into the circuit so I can turn it on and off without having to pull the plug.

I opened the wiring port on the motor and hooked up a length of romex. It has Black, White and bare. I bought an 8’ 3 prong plug that is bare on the other end. To test the motor connection, I temporarily twisted the wires together and plugged it in. Worked fine.

I went to Lowes to buy a switch and get some advice on how to do this. Not sure the guy knew what he was talking about. He sold me a 15 amp switch that has a green grounding screw on the bottom and 3 terminals…two brass on the top of the unit (one brass screw on each side) and one black screw close to the bottom, on the side.

He said to twist the black romex and black cord wire together and hook them to one of the brass screws, does not matter which.
He said to twist the white romex and white cord wire together and hook them to the one black screw. He said to twist the two ground wires together and secure them to the green grounding screw. I did -- This configuration flips my breaker.

I called my FIL, retired building inspector and all around knowledgeable guy. He said the ground connection was fine, the white connection was fine, but to untwist the two blacks and put one on one of the brass screws, the other on the other brass screw, does not matter which. I did.

This configuration flips my breaker, too.

Just to be sure, I switched the black wires on the brass screws. Same result.

Can anyone offer some advice? I think this should be easy, but I am not very good with this stuff. Am I using the wrong switch?

Any help would be appreciated.

[Jerry Miner]

You want the switch to interrupt the black-to-black connection.

(with no switch in the circuit, you have wires connected back-to-black, white-to-white and ground-to-ground. This has the machine running all the time when plugged in. You want to interrupt the circuit with a switch by interrupting the black-to-black connection)

I think the switch you have interrupts the connection between the brass screws and the black screw, so you want one back wire connected to one brass screw and the other black wire connected to the black screw. Whites connected together and grounds together.

Hope this helps. Be careful. Do not handle hot wires. Electricity is powerful and dangerous.

[Marc Ward]

Thanks, Jerry. Worked like a charm. Did not shock myself, either.

It is up and running and looking good. Much appreciated!

[Jerry Miner]

Great, Marc. We always hope we are helping. Don't always know if we are. Glad it worked for you. Mostly, I'm glad you weren't electrocuted!! :)