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Question about electric motor ratings Answered

So, lucky me, I curb surfed a table saw last friday, I was going to part it, but my wonderful wife suggested that I could benefit from an extra saw. So deciding to fix it up, I looked over the motor rating, and was left with a question. The motor is rated at 1&1/2 Hp 110v 18 amps. So my question, When is it 18 amps? Start up? Running? Stall? I ask because my breakers are 20 amp, kinda close there for comfort, and no re wiring for 220 right now is not an option.


I guess I'll determine it empirically, get it running and shove a piece of thick dense wood into the blade (I won't be that cavalier, i do know what i'm doing) if it pops the breaker, oh well. BTW first time i plugged it in, it popped the breaker, but a little 3in1 Oil on the motor bearing and it ran.

just test the internal resistivity of the motor. (put a multimeter across the power and ground wire)

Then V = I * R

110v = I * MeasuredR

the I you get will be the running current, if 18amps is way above that, then 18amps is the stall current.

does that work for a/c motors too? I would have thought there's an inductive resistance (iono, I'm not a super duper electronics guru :P)...

I'm not sure,... I'm no guru either. This is basically what someone told me a few years ago aboutn some othedr motors

I'd say that's the stall rating... At least I would hope so -- I really don't care what the running current is. I just want to know worst case scenario (stall) so I know where to plug in :P Just plug it in and see what happens ;) If your trip the breaker easily.... then part it ;) Otherwise, go forth and conquer :P

I would assume running. Don't know about load, though...