I cut off the little plug at the end of the switch tri wire and pealed the wires apart for a couple of inches and stripped the ends. I think the center wire is the common. If you power it up with your power pack and one of the others, the switch will go one way. If you power up the other outside wire, it will go the other way. Just apply power for a second. I hope this helps. I used Atlas switch controls which are all over the place for practically nothing.