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Brian Norton
01-10-2009, 11:09 AM
I am putting together my Uncle's old PM66. I just got the 230v 2 hp Leeson motor rebuilt and need a safety switch for it. There are some safety swithches at Grizzly and Woodworker's supply and the price is great.
But I am worried about an inexpensive switch burning out and harming the motor? Are those switches okay to use?
-Also There are 4 wires coming out of the motor (2 are hot!) I know those are the black ones. The other 2 that are red I was told is for a magnetic switch. Can you shine any light on that one I don't know which wires to use to hook this motor up to the switch?

Larry Crim
01-10-2009, 11:21 AM
Brian not sure about the wiring, but If you get the grizzly switch be aware the case cover screws are plastic and you must be easy on them or they will break.

Todd Franks
01-10-2009, 12:25 PM
Brian,

Food for thought, I purchased a magnetic starter from Grizzly for my cyclone and it is of the same manufacture as the magnetic starter on my Grizzly table saw. So I've got to assume the stand alone magnetic starters they sell are the exact same ones they put in own their table saws (I'll let you draw your own conclusions).

If you do decide to go with the Grizzly starters, keep in mind that when you go to get cord connectors, the threaded connector "knockouts" are not standard 1/2 & 3/4 NPT pipe threads (guess how I found out). I figured out they are a European/Asian/metric size. I found a source for the proper cord connectors from Newark. I can dig up the info and a link if anyone is interested.

-Todd

Steve H Graham
01-10-2009, 2:34 PM
Cheap switches are likely to fry on 220 circuits.

When I bought my compressor, I put a 220 circuit in my garage for it, and in addition to the magnetic starter, I installed a manual disconnect so I can shut it down if it refuses to stop. Same thing for the circuit I installed for my welder and other big tools. These things all suck more juice than a 2 HP motor, however.

You can't use the disconnect on my 5 HP compressor as an "off" switch; the current is so high, repeated disconnections melt the contacts. I had to have a starter plus a switch to start the starter!

Brian Norton
01-10-2009, 2:46 PM
Do anyone make a Safety Switch that is High end? I guess magnetic is the way to go also after all..... safety first.

Steve H Graham
01-10-2009, 4:11 PM
Great link at OWWM: http://wiki.owwm.com/(S(5ahhvmzcai0a3v45fxkhqq45))/Default.aspx?Page=Magnetic (http://wiki.owwm.com/%28S%285ahhvmzcai0a3v45fxkhqq45%29%29/Default.aspx?Page=Magnetic) Starters Explained#What_does_a_Magnetic_Starter_do_22

I don't know if 2 HP motors need starters. Maybe a big switch is enough.

Wade Lippman
01-10-2009, 11:24 PM
Any double pole switch rated for 2hp will be fine. A lesser switch could fuse shut and stop you from turning the saw off, or burn out preventing you from turning the saw on; but it can't hurt the motor.
A magnetic starter really only does one thing extra; if you lose power, it turns off. So it will not restart unexpectedly. Some include overload protection, but that is not really part of the switch.

But I am mystified by your four wires. I would ask whoever rebuilt your motor what they are for. My guess is that you tie the black together and the reds together for 120v and just the reds for 240v; but that is just a guess.

Brian Norton
02-08-2009, 9:41 PM
-Also There are 4 wires coming out of the motor (2 are hot!) I know those are the black ones. The other 2 that are red I was told is for a magnetic switch. Can you shine any light on that one I don't know which wires to use to hook this motor up to the switch?

After going back to the liscened Leeson shop...They said to just splice the reds together and the blacks are my hot! I also may want to add a ground. Which I did. It is some internal switch that was burned out so they said I didn't need it. I am aready to run this thing so I will but in new batteries in the smoke detectors I guess.

Joe Jensen
02-08-2009, 9:58 PM
Cheap switches are likely to fry on 220 circuits.

When I bought my compressor, I put a 220 circuit in my garage for it, and in addition to the magnetic starter, I installed a manual disconnect so I can shut it down if it refuses to stop. Same thing for the circuit I installed for my welder and other big tools. These things all suck more juice than a 2 HP motor, however.

You can't use the disconnect on my 5 HP compressor as an "off" switch; the current is so high, repeated disconnections melt the contacts. I had to have a starter plus a switch to start the starter!

Hmm, I've no cheap mag starters other than the import one on the Sawstop, and I've never had one refuse to stop. Are these cheap mag starters or brand name industrial ones?

Steve Rozmiarek
02-08-2009, 10:11 PM
Magnetic switches are not that hard to build with a few parts, if you so desire. You can get top flite components that way, and make it fit whatever space you have.

Steve G, I have seen big motors, 100hp, fry the contacts and keep running, but not 5hp type stuff. I'm sure it's possible though. In a wood shop, a breaker panel will work fine as an emergency kill.

Chip Lindley
02-09-2009, 12:00 AM
- It is some internal switch that was burned out so they said I didn't need it.

Brian, there is only ONE internal switch in a 230V single-phase motor, and it IS NEEDED! The starting coil is energized by the centrifugal start switch until full speed is reached. Then the start switch drops out. Other than that necessary *switch* he could have been referring to the overload reset button found on many smaller electric motors. If it was burned out, evidently now you do not have overload protection on that motor. I would have the Leeson man clarify what he meant by his comment!

Older PM66's had a heavy duty Gould mag. starter. These are hard to find now. But there are many Square D mag. starters on eBay which are industrial grade and a good place to start making your own mag. starter. Needed for your 2hp motor is a Size 1 starter with 120v or 240v coil, and (2) B17.5 heaters. Hooking up the momentary pushbutton will require the starter to have the aux. contacts for this. You can start doing your homework now looking at schematics of typical Square D mag. starters.

Or, if you feel uncomfortable with all this, Go ahead and try the Grizzly. there are many many of them out there still in service. They can't be *all BAD*!