PM66 power wirings help

[Dolfo Picanco]

I'm about to pick up a 3hp 1ph PM66 table saw and need help with some power switch wiring.
It currently works, but the previous owner threw on an exterior power switch box like the ones you would find on the outside of a house and used that as the power switch. I want to set it up with a magnetic switch and a safety flap like what's standard these days. I'm relatively new to wiring things so I'm looking for any kind of resource out there that will show me what I need to make this conversion and general information that I need to know.

Questions I need answered:
- He said there's a fuse wired up in that box. Is that something I need to get or will that be included in the magnetic switch box
- Do I need the PM66 specific mag switch box or are there cheaper, even DIY alternatives out there? (looks like its $180 for one at eReplacement parts)
- Is there an article, website, or video that goes through all of this that you trust?

any help would be greatly appreciated.

Thanks All

[Dolfo Picanco]

Correction, for the PM66 switch for $125. All questions still apply though

[Alex Zeller]

No fuse is needed. That would have been just something that was in the box the PO used. If you buy the whole magnetic switch it should be prewired. All you'll need to do is connect up the wires for the motor and power cord. It should come with a wiring schematic, if not once you have it and can post a picture of the inside we can help. You don't need to buy the Powermatic version but because they are based off of the amperage the motor draws you will need one set for the correct HP. It may cost more but the one from the newer PM2000 saw may be a better option as it should have the newer style button (the one with the on button in the center and a larger red power off ring around it). That's the style that's on my jointer and I like it much better than the one on my PM66. The green button in the center is lit when it's plugged into power and the off button is much larger than the small square button on the PM66.

[Stan Coryell]

This applies to electric motors in general.
A magnetitc starter or "motor starter" provides three basic functions. If power is lost temporarily and then restored, the motor won't turn back on. It provides thermal "overload" protection, but not fault protection. It also allows for multiple start/ stop stations.

Pictures would help.
To answer one of your questions:
No, a starter will not come fused. The fuse (one per phase) is fault protection and installed before the starter. The fuse protects the starter and wiring from a phase to phase or phase to ground fault or "short" The overloads protect the motor from over current, say if the blade binds up.
There isn't any reason you would need a switch from Powermatic.

Is the motor thermally protected?

Stan

[Dolfo Picanco]

I'm not sure if it's thermal protected, I don't have it yet and can't make out that much detail on the motor engraving.
If that fuse isn't in the starter assembly is it something I need to install? Is that something most saws have built in already?

[Alex Zeller]

Your saw will be protected by the circuit breaker that feeds the outlet it'll be plugged into. Inside the magnetic switch is where the thermal overload should be. Some motors will have one built into it (little red button) but most likely not on your PM66. If you don't buy the powermatic brand switch there's a chance you'll have to adjust the thermal overload yourself. It's usually a dial. Along with HP you will also want to pay attention to voltage and single vs 3 phase.

[Dolfo Picanco]

The red switch is there! Good to know about the PM specific switch

[Dolfo Picanco]

If I did go with a second party switch (half the price of a PM one!) how to do I determine what to adjust the thermal overload to? Where is that number(?) located?

[Stan Coryell]

The red switch is there! Good to know about the PM specific switch

The motor does have thermal protection? It should say "thermally protected " around the reset or on the name plate. Some motors have "automatic thermal protection " No reset button, the overload resets itself when the motor cools off.
You should not need to fuse it if the motor nameplate is close to the circuit breaker size.
Could you send a picture of the switch you have?

https://www.toolplanet.com/product/Woodstock-Paddle-Switch-D4151/light-electrical

This may work. We Need more information though.

Alex mentioned adjusting the thermal overload. Overloads are adjustable on IEC starters. I attached a picture, the red circle shows the adjustable overload. You would set it to the motor nameplate amps. As a side note, NEMA starters have replaceable "heaters" You match the heater to your motor nameplate amps, or Full Load Amps "FLA"

Stan

[Bill Dufour]

I would use the switch box with fuses since it is free. Mount it on the back or side where it can be got to if needed. run the power cord to the switch box then to the contactor. From the contactor run the power into the motor. Chose a control voltage you like 240 or 120 is easy with no transformer need. But some are leary of that voltage at their finger tips and use a transformer to run 24 volt control circuits.
Look up "three wire control station" for how to wire a contactor. Check ebay for a used industrial unit should be under $75 for contactor with adjustable overloads and a push button station. Easiest to buy a contactor already with a case. rather then try to figure out what will fit.
I really need to add an off switch to my tablesaw to the left of the blade. The factory mount is too far to the right and set in too far from the edge.

Search for mushroom push button switch. A lighted one costs very little more.
Bil lD

[Bill Dufour]

Probably well under 30 amp service needed.
Bil lD

[Bill Dufour]

Ebay contactor $10

https://www.ebay.com/itm/Mitsubishi-S-N10-20-Amp-32-Amp-Contactor-With-120-VAC-Coil/391352399452?epid=1601543843&hash=item5b1e6bb65c%3Ag%3ABo8AAOSw%7EotWgqjc&LH_ItemCondition=4

[Dolfo Picanco]

Okay, update with pictures!
to the saw in the other day. Looks like the switch box was a spur of the moment fix the guy did with what he had laying around the shop...so he said. Even with my relatively limited knowledge in electrical I do not see any fuses in the switch box like he said and I can see for sure that the motor is thermally protected. I can also see from the serial number that its a PM66 that was built in 2001.
My current plan is to go with a second party magnetic power switch and probably build a knee kick safety switch since that's WAY cheaper than going with a PM OEM one and I want to keep my hands on the work pieces.
Thoughts?44131844131944132044132144132244132344132 4

[Marc Fenneuff]

I can also see from the serial number that its a PM66 that was built in 2001.

Is the serial number format YYMMDDDXXXX where YY=year, MM=month and DDD=model? I tried deciphering my S/N over on OWWM but it's... well just too new I guess. I believe mine is also from 2001:
441325

Glad you're getting yours figured out. Mine came with the original Square D starter.

[Alex Zeller]

Your motor does have it's own thermal switch on it so you don't need to add one. Having one connected to the magnetic switch would just make it easier to reset if it tripped but it would need to be set slightly lower than the one on the motor. If you go with another brand than the original PM switch you can get one rated for more than what your motor is and if it has a thermal overload you can just set it so high that it'll never trip since the one on the motor will.

That disconnect on the saw now would work well for something like an air compressor.

[Dolfo Picanco]

Is the serial number format YYMMDDDXXXX where YY=year, MM=month and DDD=model? I tried deciphering my S/N over on OWWM but it's... well just too new I guess. I believe mine is also from 2001:
441325

Glad you're getting yours figured out. Mine came with the original Square D starter.

I believe this how you decipher it. I did a quick search last night and found the year correlates to the first two digits.

[Dolfo Picanco]

this is the one I was eyeing

https://www.amazon.com/Big-Horn-18823-220-240-Volt-18-26-Amp/dp/B002LVUWHM/ref=sr_1_6?dchild=1&keywords=replacement+saw+magnetic+switch&qid=1600366898&s=hi&sr=1-6

its' rated for 18-26 amps, but my motor is 15 amps. Will this switch damage my motor?

[Bill Dufour]

Should be fine as long as motor draw is less then 26 amps at full load. If it is less then 18 amps it will not do much protecting but still work just fine.
Those switches do not impress me since they are not sealed and will let sawdust in to jam things up. They will also let dust into the contactor and foul the contacts. A separate push button station and a sealed contactor box will be less prone to dust issues.
Bil lD

[Dolfo Picanco]

Should be fine as long as motor draw is less then 26 amps at full load. If it is less then 18 amps it will not do much protecting but still work just fine.
Those switches do not impress me since they are not sealed and will let sawdust in to jam things up. They will also let dust into the contactor and foul the contacts. A separate push button station and a sealed contactor box will be less prone to dust issues.
Bil lD

Good point, think wrapping the seal with gaffers or duct tape would solve that though?