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#69946 - 09/25/06 01:37 PM Run Capacitor Value
wendel Offline

Registered: 08/07/04
Posts: 57
I was servicing a generic pool pump motor. It's a Century Electric (Magnetek) 1 hp, 3450 rpm, 230/115 volt, 56J frame, part #B828.

I noticed the capacitor was badly rusting. I couldn't clearly read the capacitor's label. It appears to be 20 mfd but I need to verify that value. Possiby some of you have serviced pool motors. Does 20 mfd seem to be a reasonable value for the above described motor? I've tried to locate data on it but without success. Any help greatly appreciated... I may need a new capacitor soon.

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#69947 - 09/25/06 06:21 PM Re: Run Capacitor Value
Crowbar Offline

Registered: 01/13/03
Posts: 34
Loc: Pittsburgh, PA,USA
Century has been bought out by A.O. Smith, 20 mfd sounds reasonable to me, here is link that may provide more information.

#69948 - 09/26/06 01:53 AM Re: Run Capacitor Value

Registered: 12/08/05
Posts: 862
Loc: Titirangi, Akld, New Zealand
20 µF is a reasonable value for a 1 HP motor.
These pump motors start usually under lightly loaded conditions.

Normally 55 µF per kW for medium loaded motors I go by so the 20 µF should work fine.
The product of rotation, excitation and flux produces electricty.

#69949 - 09/27/06 02:02 AM Re: Run Capacitor Value
pauluk Offline

Registered: 08/11/01
Posts: 7693
Loc: Norfolk, England
From Alan Belson:

I'd go for about 20uF per horsepower, if you can't read the OE label, but I'm told by my friendly Scot neighbor "dinna gae any higher".

And I second the comments about frequent starts - Pic, "balloon capacitor", is what happened when I pushed a 3hp motor too hard.
BTW the motor still just about started, [after a struggle], which reason led to the discovery of the problem.

Rod, 55uF per kW?

[This message has been edited by pauluk (edited 09-27-2006).]


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