motor overload protection

[John Beck]

Is there a way to provide overload protection to a 3hp grizzly motor? Original mag. switch ruined by katrina. I don't want to spend $70 plus shipping for a new enclosed starter if I can help it

[Rod Sheridan]

Hi John, the alternative to a magnetic starter is a manual starter.

A manual starter can either be a mechanical push button type, or a toggle switch style. For both types, you will need to purchase the correct overload elements for your motor.

If it were me, I would go with a new mag starter, which prevents automatic motor restart after a power failure.

Regards, Rod.

[Wilbur Pan]

You should also consider that a new 3 HP motor will run you around $300, should it blow up. Makes getting a new starter look cheap in comparison.

[John Beck]

Wilbur Pan : New switch is best long term solution. Thank you. Any good souces for a new one? Grizzly out of stock til new year.

[Wilbur Pan]

Disclaimer -- you didn't say what this motor was for, but I'm going to guess is that you have a 3HP motor running on 220V used for a tablesaw.

My usual go-to sources for these things would be Grainger, McMaster-Carr, or MSC. But the magnetic starters that these places carry are real industrial-duty magnetic starters that would be about $250-300. I would wait it out until Grizzly has them back in stock. I think that Taian makes those starters, if that helps.

You could look on eBay, but you need to have some idea as to what you are doing.

You could also look in your local yellow pages for a place that services electric motors. Many times they will have used magnetic starters that were pulled from machines that weren't running. In these cases, the starters are just fine.

Finally, you could go with a manual motor starter with overload protection, but if what you are using this motor for is a tablesaw, then, as Rod said, I would go for a magnetic starter.

[Rob Will]

I would go to a local motor repair shop and ask about a used magnetic starter. Be sure the coil voltage is correct for your application and be sure the heaters are properly sized and set. If you take it apart, clean the electrical contacts. Also clean the seating surfaces of the magnet. This helps to eliminate magnet buzz.

Sometimes surplus houses that deal in industrial machinery will have magnetic starters for sale.

Rob

[Chris Friesen]

Wilbur Pan : New switch is best long term solution. Thank you. Any good souces for a new one? Grizzly out of stock til new year.

Don't know if they have them in stock, but "House of Tools" up here in Canada carries them. They're around $100.

You need to pick the one with the right specs for the motor. This one is for 12-18A, 220V, 1phase.

http://www.houseoftools.com/product.htm?pid=18369