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Capacitor calculations

Capacitor calculations

Capacitor calculations

(OP)
Is there any way to calculate the capacitor value of a permanent split phase motor?
The motor spec is 1700rpm 1/15hp 60Hz 1ph 1.0amp
The cap value at the moment is 10 mfd but the motor is running on a 50Hz supply and getting very hot.
I know I need to increase the cap value but don't know by what.
Any help would be much appreciated.

RE: Capacitor calculations

Some 60Hz motors won't tolerate 50Hz operation.

How many amps is the motor drawing?

Keith Cress
Flamin Systems, Inc.- http://www.flaminsystems.com

RE: Capacitor calculations

If the applied voltage is the same as for 60 HZ, the magnetic circuit is saturated since the flux increases with inverse proportion to frequencies.That will overheat the motor.
A larger capacitor could drop the line current but the current going into the motor windings is the very same, the only difference is the capacitor providing the reactive power instead of the line. Provide more information.

RE: Capacitor calculations

(OP)
itsmoked
The motor pulls 0.3 amps off load

aolalde
What other information?

RE: Capacitor calculations

Hard time seeing it draw only 1/3 of rating but getting hot..

Is the meter a True RMS meter?

Keith Cress
Flamin Systems, Inc.- http://www.flaminsystems.com

RE: Capacitor calculations

(OP)
OOPS

It's pulling 0.5amps not .3
The meter I used first time needs calibrating I think (or bining)

Ian

RE: Capacitor calculations


Aolalde; What other information?

OPERATING VOLTAGES AT 50 and 60 HZ?

Sorry for the late answer, some days I do not have the time to log in.

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