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Hello, this is my first post, thank you for having me. Looking forward to contributing and learning. I recently started the wiring of an older Unisaw and have run into an issue with the switch. I cant seem to make head or tails of it but, in the end need to get it wired. Any help would be appreciated.
 

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You have low-voltage controls on the front of your saw. All of the main power is in a large junction box on the rear of the saw. To make this system work, there are 3 wires up front. One wire will be common to both switches. One wire will be Normally Open (N.O.) and one will be Normally Closed (N.C.)

If you can take a picture of these 3 wires back in the rear junction box, I can probably determine which wire is which. IOtherwise, here is a simple set of tests that I think will isolate which is which.

Briefly touch any two wires together, and see which pair causes the motor to start. One of those wires will be common and the other will be N.O. (releasing those 2 wires should stop the motor.)

Hold all 3 wires together (the motor will start), and one at a time, remove each single wire from the other 2. You'll have to repeat this for each wire. If removing a wire does not cause the motor to turn off, put it back on, and pick a different one until the motor stops running. This wire is your Common, and connects to the center screw of your switch.

Now you know which one is Common and which one is N.O., so by elimination, you also know which one is N.C.
 

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DOH! I missed something rather obvious above. If you know that the pair of wires in the first step are N.O. and common, then obviously the 3rd wire is already known to be your N.C. wire. Go ahead and connect that to the switch.

So now you are down to a 50/50 decision about the first 2 wires. Go ahead and wire all 3 to your switch, knowing which one is definitely N.C...If pressing and releasing the start button causes the motor to start but shut back off, then reverse those two wires, and you're done.
 
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