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Capacitors for GE 60Hz rated motor on 50Hz

Capacitors for GE 60Hz rated motor on 50Hz

Capacitors for GE 60Hz rated motor on 50Hz

(OP)
I have to use 60Hz rated motor in Europe on 230/50Hz power, but it hardly starts(sometimes not at all). Plus heats quickly.

I think this is frequency issue and canging capacitors might help. I've searched the net but can not find any info
how to calculate required capacitance for 1 phase AC motor versus frequency change.

Any tips on that? Do you thing right caps would help?  

Also I'm looket if I can use a VFD to change frequency but all they are 1ph inp to 3ph outp, while my motor wants 1ph.
Anybody knows economic solution to change frequency 50Hz->60Hz if caps not help?



There is motor info:

Capacitors installed:  1000mkf (60Hz) and 15mkf(60Hz)

Brand: GE
Model: 5KC49ZG530
HP  1.5
Hz 60
V 115/230
PH 1
RPM 1725   CODE J
A 14.8/7.4     SF 1.0
SFA   FR 56C

For 115V wire connection:
BLUE(T1)+RED(J10)+ORANGE(T3)=> all connected to Mains wire
Yellow(T4)+BLACK(T5)+WHITE(T2)=>all connected to Mains wire

For 230V wire connection:
BLUE(T1)=> connected to Mains wire
RED(J10)+ORANGE(T3)+WHITE(T2)=> interconnected together
Yellow(T4)+BLACK(T5)=>both connected to Mains wire


For changing rot direction meed to interchange RED(J10) and BLACK(T5).


Somegbody recognizes it?

RE: Capacitors for GE 60Hz rated motor on 50Hz

Before worrying about the capacitor, you need to replace the start switch with one intended for 50Hz, your motor is never switching from start to run because it never goes fast enough.  Beyond that your 230V rating becomes only 192V for 50Hz so you are subjecting the motor to an overvoltage of about 17% and it won't take that for very long.  Best to buy a new motor and do it right.

RE: Capacitors for GE 60Hz rated motor on 50Hz

Yep, it has little to do with the capacitors. Start switches are designed to take the caps out at 90% speed. 90% of 60Hz is 54Hz. You are only giving it 50Hz; it never gets there.

By the time you fix that and buy a transformer to fix the voltage problem, you will also discover that you have less HP now, which may likely affect the loading. Do yourself a favor and follow davidbeach's advice.

And just to head off the inevitable VFD responses from the uninformed (or those who will fail to notice that you have a 1 phase motor), the few VFDs that are capable of running 1 phase motors are NOT suitable for use on cap-start motors anyway, so don't even bother going that route. Yes, you could consider replacing your motor with a 3 phase version, THEN get a VFD to accept your 1 phase power and give you a 3 phase output, but think it through... a new 50Hz motor is going to cost a LOT less.

RE: Capacitors for GE 60Hz rated motor on 50Hz

OP says the motor hardly starts or doesn't start at all. Also, motor overheating suggests locked rotor issue.

May be it is the start capacitor gone bad after all.

Once it starts, V/Hz issue still remains however.

*Why a man thinks he outrun a chasing dog when it has twice as many legs?*

RE: Capacitors for GE 60Hz rated motor on 50Hz

Correction

Once it starts, V/Hz issue and centrifugal switch issue still remain however (as davidbeach and jraef say).

*Even inside a hard-boiled egg, there is a golden heart!!!*

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