I have a 12 inch chraftsman table saw with 2 wires coming from motor. The wiring diagram inside the cap shows it to be wired for 240 how do I wire that thru a switch and to a three wire recepticle
Not quite sure what your question is - Are you trying to plug a 240 into a 110/120 outlet? Or are you trying to plug this into a 240 3 prong outlet?
Traditionally, table saws don't come with a power cord - you must supply one. Usually on the motor there is a metal plate that describes volts/amps/phase/hp etc. Get the Volts/Amps from this plate, then measure the approximate distance between your table saw and the 240 outlet. The gauge of the power cord depends upon the Volt/Amps and the length of the cord. There are many volts/amps vs length for wire gauge conversions on the net. I always get a bigger wire (smaller gauge) than what is recommended. Expect to pay $100 or more for the cord (don't be cheap here). If you have an under rated cord, you can start a fire, burn up your motor, melt plugs into outlets and have to replace the outlet (don't ask how I know).
I'm a little suspicious of the "white and black" wire from 240 - it's usually "white and red" with a "black" ground. 240 is made from two 120's - opposite sine wave. So black is usually the common ground, while the white and red are the two 120's. Volts between white-red=240, white-black=120, red-black=120. If you're absolutely sure that white-black=240, then you can just connect a ground wire to the motor case. Many home table saws can be wired for 240 or 120 - you need to make sure that you're hooking 240v to the correct wires. If you're uncertain at all, then don't do it.
I have wired 120 to a 240 motor by accident and the motor ran - it had no power and didn't spin at full RPM. You can damage a motor this way, so I wouldn't recommend it. I have never put 240 to a 120 motor - so I don't know what happens (guessing you could burn up the motor coils).
With all that being said, if you have 240 outlet with 3 wire receptacle, then just use a multi-meter to determine the 2 "hot" and the 1 ground. Volts from hot1-hot2=240, hot1-ground=120, hot2-ground=120. If you don't have a multi-meter, buy one (approx $12). Once you have it wired up, then try the motor by flipping the switch on then off again. If the motor didn't spin, then you did something wrong. If it hummed but didn't spin, you have some connections wrong inside of the motor. If it spins the wrong way, then your wiring inside of the motor is wrong (doesn't help to flip the wires on the outlet). If you blew a circuit breaker, then the wiring to the motor is wrong.
Sep 27, 2014 |