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Magnetic Motor Starters

RJINATOR

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Jan 23, 2025
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Hello. First post here. I purchased a late 40s Rockwell/Delta 6x48 belt sander last night. When unloading it we broke the switch box off the front. Inside the switch box was a Square D Nema 00 motor starter. The motor on the belt sander is a late 80s 1HP Dayton 115v/230v with a capacitor start. My question is this magnetic motor starter needed? When and what application are the supposed to be used.
 
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manwithtools

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Magnetic motor starters will have thermal overload protection built into them, this is required for motors that are not thermally protected internally (check your motor for thermal protection labeling). Also magnetic starters offer operator protection in the event of power loss, they will not restart on power restoration without an operator pushing the start button. This is important for things like saws, etc. In the case of you your sander, you probably don't want it to restart automatically after power interruption.
 
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RPH

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We need photos of damage and data plates. I believe you need 5 posts to get photos loaded on the site.
 

dave*99

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Hello. First post here. I purchased a late 40s Rockwell/Delta 6x48 belt sander last night. When unloading it we broke the switch box off the front. Inside the switch box was a Square D Nema 00 motor starter. The motor on the belt sander is a late 80s 1HP Dayton 115v/230v with a capacitor start. My question is this magnetic motor starter needed? When and what application are the supposed to be used.
Is there a red pushbutton on the Dayton motor? Perhaps labelled overload?
 
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Norcal

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Mar 16, 2008
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My Rockwell 6X48 sander has a NEMA 4X enclosure with a obsolete Cutler-Hammer Citation mag starter. They have been obsolete since the mid 1990's but I like em, & have tubs of them, 12 starters to the tub + parts.

Edit: It is a "Frankensander" a combined mixture of 40's & 60's sanders one, was open stand model, & the other was on a closed steel stand, the most prized models are the ones on a cast iron art deco stand, a period correct through that time is a Cutler-Hammer art deco manual motor switch, which can go for some serious money.
 
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fitter30

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Square D was the industrial standard of starters they made millions of them. Ebay or salvage electrical store Probably find your part if needed.
 

KenC

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the main reason for mag starters on tools is to prevent unintended restarts. Say a breaker trips while sanding something. You leave the 'something' on the belt or against the disk. then go reset the breaker. Without a mag starter the sander (saw,grinder, whatever) will restart when the power is restored.

If you're ok with not having that level of safety, a motor rated switch will work.
 

Norcal

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the main reason for mag starters on tools is to prevent unintended restarts. Say a breaker trips while sanding something. You leave the 'something' on the belt or against the disk. then go reset the breaker. Without a mag starter the sander (saw,grinder, whatever) will restart when the power is restored.

If you're ok with not having that level of safety, a motor rated switch will work.
The above only applies if wired for 3-wire control, 2-wire control will restart if power is restored & the switch is on.
 
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