PWM Motor Speed Control

old toolmaker

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I have an old drill press having a 1/4 hp AC 115 volt split phase motor from the 1950's.
Can I use a PWM motor controller to control the motor speed? There are several available on EBay.
I am looking for a quick way to adjust speed other than changing belts. Most all my work is with smaller drill bits.

Dick
 
I am by no means an electronic genius, but I think PWM only works for DC motors.
 
I am by no means an electronic genius, but I think PWM only works for DC motors.
Hi Bob,

Thanks for your response.
Maybe the acronym I used (PWM) is not correct and I just assumed it was. There are cheap devices on E Bay that are meant for use on AC motors which I have on my drill press.
These devises are advertised for use on AC motors but I realize there are several kinds of AC motors. Mine is a split phase motor. I am not an electrician or electronics expert by any definition, so I need some guidance.

Dick
 
I believe you need a brushed a/c motor to use one of those cheap speed controls on. motor label will say a it's an a/c d/c motor.
 
I forgot to mention in my last post that unit I am looking at on E Bay is very similar to what Grainger sells for router speed control. You plug it into an AC 115 V outlet and plug the motor cord into the unit and it has a speed control knob.

Dick
 
I believe you need a brushed a/c motor to use one of those cheap speed controls on. motor label will say a it's an a/c d/c motor.

This may sound like like a silly question, but how can a motor be both AC and DC?

Dick
 
Sorry Dick it won't work with a split phase motor, don't waste your money. It has to be a brush type motor, or a shaded pole induction type (fan motor).
Mark S.
 
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There are ac/dc types and they have brushes. They don't have great speed regulation. I believe vacuum cleaners are one example. Some types of power tools.
Mark S.
ps I think Wikipedia has some info on them, if you're interested.
 
Sorry Dick it won't work with a split phase motor, don't waste your money. It has to be a brush type motor, or a shaded pole induction type.(fan motor)
Mark S.

Thank you, Mark.

I went and looked at my motor information plate and it does not say split phase. I don't know where I got the notion that it was. How would one know if it is split phase?
If it is not split phase would the motor control work?

Dick
 
Thank you, Mark.

I went and looked at my motor information plate and it does not say split phase. I don't know where I got the notion that it was. How would one know if it is split phase?
If it is not split phase would the motor control work?

Dick
Show us a pic of the motor.
 
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