Replacement overload switch


byegge

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My overload switch crapped out on me on Monday during a rip through some 2 in beech. It won't reset. Removed it and cleaned up the best I can but won't lock down. I bypased it for now, making sure to go slow. I've tried looking everywhere for a replacement. It's an older jet contractors saw jts 10. Anyone got a line on some of these. Nothing from the jet website. Found one one eBay but is used and looks as old as mine. Thanks in advance for your help. 

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  • 2 weeks later...
43 minutes ago, byegge said:

Thanks butcher, I ordered that part you listed on a whim. Just got it in and it is only a two pole where as I need a 3 pole switch. Guess I'm off to the surplus store. It's been way too hot out lately to be in the shop anyway. 

3 phase motor on a contractor saw? That's very unusual. Is that an overload switch that is part of the motor or is it what you turn the saw on & off with?

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34 minutes ago, wdwerker said:

3 poles on switch could be hot ground and neutral or hot, hot , neutral if it's a 240v saw, but not 3 phase. 3 phase usually has 4 wires or more, 3 hots & neutral.

But 3 phase has only 3 hots, a ground, no neutral & the ground is never switched. So for controlling the motor, you need a 3P switch for 3 phase, 2P switch for 240V single phase & only a 1P for a 120V motor cause the neutral doesn't need to be switched. Some 120V saws may have a 2P switch so they can be connected for 120V or 240V

If it's just the overload switch that mounts on the motor, then it can have a number of terminals, depending on the motor.

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Three phase switches have six poles. Single phase have two because one phase is broken. Three phase have six because three phases are broken as they are all "hot." Switches for 240/110 often have four poles and a jumper. 

EDIT: I am not an electrician. Maybe "pole" is not the right word. The problem is that even simple switches with magnetic protection and special ignition circuits will have lots of terminals. 

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15 minutes ago, C Shaffer said:

Three phase switches have six poles. Single phase have two because one phase is broken. Three phase have six because three phases are broken as they are all "hot." Switches for 240/110 often have four poles and a jumper. 

EDIT: I am not an electrician. Maybe "pole" is not the right word. The problem is that even simple switches with magnetic protection and special ignition circuits will have lots of terminals. 

I'm an electrician. You've got the concept right, terminology's just a little off.. 3 phase uses a 3 pole switch, each pole has 2 terminals; a Line terminal (L1, L2, L3) & a load terminal (T1, T2, T3). If it has overload protection & is a magnetic switch, it'll have 2 coil terminals, at least 1 set of contacts on the overload relay, a holding contact on the main contactor & the complexity can go up from there.

The OP's post has me confused though. Given that it's a contractor saw it probably has a single phase motor & they almost always have an overload switch built into the motor (red button on the end of the motor). Those switches may have 2 terminals or 3. Probably 3 if it's a 120/240V motor. If this is the case, then they are pretty cheap & easy to get.

A motor repair shop will be able to provide one and ensure that it's the correct one. Might pay a few bucks more than online, but you only buy once that way

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