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View Full Version : Toggle Switch Rated for Tools. Six Connection Points. How Come?


Clough
Oct 10, 2009, 02:34 AM
Hi, All!

I just bought a new, generic switch for a bench mounted power tool that I have. It's a toggle switch. I needed something that had a ground connector.

I figured out how to connect things up and everything is working fine! However, this switch has six connection points on it.

I'm wondering why...

Thanks!

KISS
Oct 10, 2009, 02:48 AM
So, it's a DPDT or Double pole Double Throw / ON-none-ON switch.

If I used (ON) that would indicate momentary. If I used ON-OFF-ON, that would indicate center off. So, that's basically how you describe the action of a toggles switch.

Now, I have seen switches with 4 terminals, although it's extremely rare. Someone really has to have the volume to support using a little less metal in it. Besides, now people want to reduce inventory, so why stock one with 4 terminals.

In DC applications, this could act as a reversing switch if you cross the end terminals and attach 4 wires; 2 to the center and 2 to one of the ends. If you connected a 9 V battery to say the middle terminals, the polarity would switch based on the position of the switch if you measured the voltage on the other two wires.

This same DPDT arrangement is used on PSC (Permanent Split Capacitor) motors like those used on ceiling fans to reverse the direction of rotation. You reverse the magnetic field on one of the two windings.

Clough
Oct 10, 2009, 02:52 AM
Hi, KISS!

You're over my head here! Is this swtch okay to use with my bench grinder? I purchased it to replace another really old switch that I had used to replace the original switch on the grinder.

Thanks!

KISS
Oct 10, 2009, 02:58 AM
Yep, as long as the voltage and current ratings are appropriate for the motor horsepower.

If you use it a lot, I would get a horsepower rated switch.

Clough
Oct 10, 2009, 03:15 AM
Where would a person get a horse power rated switch, please!

I got the present switch at Menards. Might that not be what I purchased?

Like I said previously, in my other thread, I did use it for several hours, tonight.

I'm looking for education here. Don't know all of the correct terms to use nor things to say.

Thanks!

KISS
Oct 10, 2009, 03:26 AM
Heavy Duty (http://www.wiringproducts.com/contents/en-us/d130.html)

The 73185 (this will have 2 terminals) or the 73120 (this will have 4 terminals). The first is rated for 3/4 HP and the second for 1-1//2 HP, so the latter is the better switch.

The ratings are usually marked on the switch.

You can get HP rated switches that look like a standard house on/off wall switch.