Potter & Brumfield Magnetic Switch?

[John]

I bought a table saw that I want to change to 240v.

As nearly as I can figure, the power cord goes to a Square D pull out switch (FP222R). From there it goes to a large Reitech momentary contact switch (EZO-MS), and then to a Potter&Brumfield device of some sort, and then to the motor. Unfortunately the part number is rubbed off the P&B device, but it is a coil with some contacts on it, so I presume it is a magnetic switch. I can make out 120v, so I am guessing it only good for 120v.

A picture of it is at

this guess likely correct? How would I go about changing to one capable of handling 240v? If someone is familiar with Potter & Brumfield switches, I would be grateful for your help.

[George M. Kazaka]

Most Mag switches run on 110/120 volts even if you are using 240. Even my 3 phase equipment that has mag starters are only on a 110 leg. There should be a wiring diagram inside the cover, to tell you how to wire it,

> Is this guess likely correct? How would I go about changing to one capable

[Greg]

That would require a 4 wire power cord to be "legal".

[Wilson Lamb]

You're going to need some adult supervision on this. As in other messages, the coil has to be 120V if the tool was running on 120V before. You have to be sure you are switching both hot leads and that the coil runs from one hot to neutral.

I don't think you need a fourth wire, but code may ask for it. It's up to you. Mine are all on 3 wire plugs.

I think talking you through this is more trouble than it's worth, unless you find and can understand the schematic. Someone knowledgeable can do it in five minutes. Don't you have any electrically oriented friends??

The magnetic switch is also called a relay. I'm sure you can find a description through google, but not an exact schematic.

Be careful!

[John]

I have identified the part as a PM-17AY-120. The manufacturer suggests replacing it with a PM-17AY-240 for $90. That is a little out of my budget.

I haven't managed a schematic on it, but this is a catalog page on it.

chance of making this work? Any way to get the schematic?

Thanks.