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Last weekend I picked up an older tablesaw ($20! Gotta love Craig's List) with the intent of either using it for the base of ShopNotes thickness sander or just stealing the motor for the thickness sander. Either way, it was worth the $20 just for the motor.

When I was futzing with it last night I realized that the motor wasn't a 110 as I was told, but a 115/230 1HP. SCORE! I want to wire it for 230 and it looks simple enough. They numbered the wires and supplied a nice little diagram. My question is, do I need a 220 switch or can I use the rocker switch that's on it?

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Aoibeann

If you wire it for 220 you will need a double pole switch to control it. 220
has two live leads (+110 & -110) instead of one live and a neutral. You
could check the switch to see if it's a double pole, but on an older tool it
may be better just to replace it anyway.

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Eschew obfuscation, espouse elucidation.

Thanks David.

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Aoibeann

Lillian-
Recommended switch would be double pole, but single pole switches work fine, as long as you are plugging in the motor to an outlet. Your kitchen stove has single pole switches controlling the 220v elements...there are many other examples.
A 1 HP motor will only be drawing about 5A on 220v, so practically any standard switch will do the trick. A magnetic-type control would be overkill for a 1HP motor (my opinion only).
The breaker/fuse for a 220 v circuit has to control both legs, but the switch needs to control only one.
HOWEVER, you must understand that there is still 'live' AC inside the motor even with a single-pole switch turned off. So it's important to pull the plug before you mess with the wiring....in case there is anybody who doesn't do that already.
Cheers
John

Is there an advantage to using a magnetic switch over a double pole switch other than safety if the power goes out and comes back on suddenly?

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Aoibeann

[QUOTE=Aoibeann] Is there an advantage to using a magnetic switch over a double pole switch other than safety if the power goes out and comes back on suddenly?[/QUOTE]
Some motors have a thermal overload that can reset automatically (no red button) and the mag switch will prevent re-start.
Again, the standards you need for a commercial/industrial environment with many people (not all paying real close attention) using equipment are probably more strict than required in a home shop.
If in doubt (if you are shaky on electrical theory/practice) and if you have the cash, you can't go wrong following the commercial/industrial standards.
John

You can also use the mag switch to make a safety switch that can be knee or foot activated - you cant realy do that too easy with a toggle. I woudlnt want anything esle on a table saw as it allows you to make a cut and hold the piece with both hands if necessary, and turn the saw off with a knee ... thats what my Unisaw is set up to do, it was quite easy to add a plywood paddle on a hinge, with a prtruding dowel to activate the stop button. A simple hole thru the paddle allows access to the start button. Dont have a pic handy ...

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Tony Karol
www.karol-guitars.com
"let my passion .. fulfill yours"

I'm gradually switching a number of my tools over to magnetic switches.
Although the chances certainly are slim, I've always had a fear of shut off
and restart during a momentary power outage (Chances are also slim for
a car crash of course, but I still wear my seat belt.). A lot of my tools are
3 phase so they need special starters anyway, but magnetic are safer for
you and your motor. I've already refit my table saw with a Furnas
magnetic switch and set it up with a knee kick button, and have one of
the Grizzley switches (man those are cheap!) that I have yet to install on
my milling machine.

In my opinion any tool could potentialy throw or swing a board if the
power were to go off just long enough for you to remove your hands, but
not long enough to find the switch, deserves a magnetic starter or
undervoltage trip. Table saws, drill presses, jointers, milling machines,
shapers, etc. If I had the money I would install undervoltage trip breakers
at the main box, but man those are rediculously expensive.

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Eschew obfuscation, espouse elucidation.

Do not under any circumstanses use a single pole switch to control a 220V circuit. The single pole switch will turn the motor on and off, but the voltage will still be presant in the motor and wiring which will present a potential hazard to anyone working on the equipment in the future. If you are going to do something do it right especially when working with electricity.
By the way, the elements on a kitchen stove operate on 120V each even though the stove itself is wired for 220.

Regards, AlA Peebels39090.5814930556

[QUOTE=A Peebels] Do not under any circumstanses use a single pole
switch to control a 220V circuit. The single pole switch will turn the motor
on and off, but the voltage will still be presant in the motor and wiring which
will present a potential hazard to anyone working on the equipment in the
future. If you are going to do something do it right especially when working
with electricity.

Regards, Al[/QUOTE]


Hear, Hear.

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Eschew obfuscation, espouse elucidation.

Al, that's exactly what I wanted to hear.

Thanks guys.

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Aoibeann

I guess working on electrical equipment for 37 years is good for something.

Al