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Old 03-08-2021, 11:58 AM   #41 (permalink)
Stubby79
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Quote:
The synchronous speed for an AC motor is determined by

the power supply frequency, and
the number of poles in the motor winding.

The synchronous speed can be calculated as:

n = f (2 / p) 60 (1)

where

n = shaft rotation speed (rev/min, rpm)

f = frequency of electrical power supply (Hz, cycles/sec, 1/s)

p = number of poles

Electric motors - Synchronous speed vs. frequency and no. poles
I'd hazard it would only be running at like 600 rpm due to the number of coils in it. At 40rpm/v, it would only have 15v of back EMF, and the rest of the 208v or whatever it peaks at would have to be dissipated across the coils. It would get hot in a hurry.

The reasonable thing to do is to check the frequency of the output when spinning it. I'll do that next time I'm mucking around with it.

Edit:
1200rpm.

It's giving me 67hz at 1350rpm, which works out nicely to 1200 at 60hz.


Last edited by Stubby79; 03-08-2021 at 12:34 PM..
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