Question RE Mag Starter / Switch

[Chris Fierro]

Hi. I am pretty new here. I scored a King 10" tablesaw a while back and am in the process of rebuilding it. Since I don't have three phase and do not want to go the converter route, I am planning on installing a Leeson motor (145T, 3 HP) that I will purchase locally.

I thought I understood this well enough to know that all I needed beyond the motor was a magnetic switch. (I ordered a Grizzly #G4573) I then started reading about magnetic starters and I am now unsure if they are indeed two separate things or not.

Will the Grizzly G4573 cover me, or should I look for a separate NEMA 1 starter?

Any help from the Gurus would be appreciated. Suddenly I am feeling a little overwhelmed that my $200 saw purchase is going to turn into a quagmire. I am ready to spend $300 on a motor and just spent $80 on a switch. I am fine with the mechanics, but intimidated by the electrical.

Thanks in advance!!

-Chris F.

[Matt Meiser]

Yes, the G4573 should do exactly what you want. It is a magnetic starter. Nema 1 is a US-based standard for a size of magnetic starter. Most stuff is converting over to IEC standards. Regardless, the one you listed is rated for a 3HP motor which is what matters.

[Chris Fierro]

Thanks, Matt. I was pretty sure that this was the case, but I had a little bit of a panic attack. The Grizzly support person was helpful and reassured me that we were using different terminology to discuss the same thing--but he was thrown off when I asked about the NEMA spec. Hence my panic.

And since I know the "no photo / didn't happen" rule;



And to offset the $200 price of my saw, it came with a $200 blade!



Thanks again!

[Steven Wilson]

Chris, You might be able to change out some of the internals of that Square D starter to make it work for your single phase source. Square D is good kit.

[Steve Clardy]

Your griz switch will work.

Your present box will work also. Just don't use the center terminals. Use the outer terminals for single phase.

[Matt Meiser]

The Steves are right. If the coil on the SquareD isn't rated for 240v you should be able to change it out for a 240v one and use it. Can we get some closeups of the guts of it?

[Chris Fierro]

Matt,

Here are the closeups. I already ordered that Grizz mag switch. So I have no use for the SquareD unit, at least in the context of the tablesaw. (RIGHT?)

[Steve Clardy]

Ok. Thats just a fused On/Off switch.

Magnetic switch will be safer. Power goes off, saw stays off till you push the button again.

[Murray Roblin]

Chris,
Congrats on your "new" saw. I have a mid-50s walker turner which is great.

Check out the forums at www.owwm.com and do a search on magnetic starters. There has been quite a bit written over the past few years and this should give you an idea as to what you can do and how you should wire the starter.

wrt Steve's comments about bypassing the center terminal for single phase operation: From extensive discussions on owwm, the consensus seems to be that in order for the heaters to work properly (i.e. trip the circuit when too many amps are pulled), the center heater circuit should be wired in series with one of the other legs.

Murray

[Matt Meiser]

Oops. What is the box with the pushbuttons wired to? Directly to the fused disconnect switch? Is it a mechanical pushbutton like most of the mid-market tools have now?

[Steven Wilson]

Matt, I thought that was a remote control station for the SquareD, but since the big box is a fused On/Off switch maybe the buttons are something interesting (or mechanical pushbuttons like you surmise). If it's just pushbuttons then I'd remove that stuff and go with the Griz switch. Of course that SquareD disconnect would come in handy if he ever hardwires a machine.

[Matt Meiser]

Even if he doesn't hard wire it. I have a disconnect at My table saw to provide a convenient place to kill the power without messing around with the twist lock plug. Lowes had the Siemens 30A disconnects pretty cheap and I picked a couple up.

[Chris Fierro]

There was a mechanical "up / down" pushbutton switch coming off of a 14/3 cordset. I am going to just throw all of that stuff aside and wire up the Grizzly switch to a new Leeson motor. Some of the wiring work was very shoddy looking and one of the terminals appeared to have been sealed with Bondo. The guy that I got this saw from was a little nuts, although supposedly a competent wood worker.

I had looked through the OWWM websites and the magnetic starter article over there was actually what got me confused. At any rate, I spoke to an electrician and I seem to be good to go. He is going to drop 20A 220v in my shop on a 6-20 receptacle. I am having the motor wired to match from the retailer. Just need someone to double check my wiring up of the mag switch. Should be good to go.

Thanks so much everyone!

[Matt Meiser]

That magnetic switch is going to need to be wired between the cord set and the motor. Incoming power will go to the switch, which will send power to the motor only when requested.