Circuit for Disc Sander

[bad_idea]

I have an older Rockwell disc sander. It draws 18 amps on 120v or 9 amps on 240v. It is currently wired for 120v and I have it plugged into a 120v outlet on a 20 amp circuit. It is slow to start and is popping the breaker most times. If I spin it by hand fairly quick then it will start up and run good. I ASSume the capacitor is shot, though I am concerned it may be too much draw on the 120v circuit and that is the issue. Thoughts?

I am in process of running outlets into the garage and I am considering pulling in a 240v circuit for the disc sander. Do you all think that will fix the issue, or do I need a new start capacitor?

Thanks all.

 

[Jim greengo]

I'd try a new capacitor no matter what voltage you put it on.

 

[klassenl]

I am in process of running outlets into the garage and I am considering pulling in a 240v circuit for the disc sander. Do you all think that will fix the issue, or do I need a new start capacitor?

Thanks all.

Whether it will "fix" the "problem" or no run some 240v circuits it opens up other possibilities beyond your immediate situation.

 

[dogdog]

I'd try a new capacitor no matter what voltage you put it on.

this one... check the cap (s) first.

and also check if you have that centrifugal switch sticky or badly pitted, or just bad. if it is an AC induction motor.. dependents on how old the motor and the type of those switches.....

 

[sberry]

It wouldn't hurt to run it on a higher voltage. That is a machine is pretty greedy. I would be tempted to hook it on to a 20x240 but its heavy enough it might go on a 30, shou;ld never trip at that. If you can get the price on a cap it doesn't hurt to change old ones, I went fussing with them at times and find the wire falling right off, no ****,,, helps with wondering and about like changing a spark plug on really old stuff, cant hurt.

 

[Stuart in MN]

A motor that's rated at 18 amps at 120vac or 9 amps at 240vac sounds like a 1hp motor. It's too big for a 120vac, 20 amp circuit, so that could certainly be the cause of the breaker tripping. I think you either need a higher amperage 120vac circuit, or change the motor over to run on 240vac. I'd wait until that's done before worrying about the capacitor.

 

[bad_idea]

The walls are open (no insulation or sheetrock) and I have the wire. I'll grab a 240v 20 amp breaker and an outlet next time I go to Lowes. Should be an easy run. I have a few capacitors laying around, I'll have to see if one fits it (if it keeps acting up after I run the circuit).

Last question - is there any wiggle room on capacitor size?