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cap start & run reversing single phase problem

cap start & run reversing single phase problem

cap start & run reversing single phase problem

(OP)
I replaced a 7 1/2 hp weg motor,i am having the same problem as the original one. the start cap is blowing up.
This motor is used on a Right Way power winch, with momentary push buttons for up and down.
The customer jogs the buttons when they get close to where they want to be.
The controls are wired with one line going right to the motor?
Motor windings have 1-2-5 & 3-4-8
Centrifugal switch also burned together
thank you

RE: cap start & run reversing single phase problem

All of  your problems are from the JOGGING!

The start capacitor has no time to cool off and they are also rated in the numbers of starts per HOUR!

The start switch too will get too hot and weld itself together!

Your typical motor can't take that kind of abuse for long!
You may get away with DOUBLING the capacitors rated voltage and changing out the start switch with a heavier duty one.

If that fails to help, a motor designed for that kind of abuse may have to be acquired.

RE: cap start & run reversing single phase problem

Suggestion: Normally, jogging (and possibly plugging) requires a heavy duty service motor. These are usually three phase squirrel-cage induction motors. Similarly, the single phase motor should be designed for the heavy duty service.

RE: cap start & run reversing single phase problem

Your title mentions reversing... does the winch and controls not work too? Or is it just the capacitor and switch you have problems with? Please elaborate.

RE: cap start & run reversing single phase problem

I believe I know your motor exactly, have used hundreds of them.

Our experience leads me to suspect your centrifugal start switch may be a problem.  None of the manufacturers have great centrifugal switches, and Weg's is near the bottom of that list.

Our company policy allows use of single phase motors only if there is no jogging, no frequent starts.  The centrifugal switches from any manufacturer will be a problem.  Jogging is tough for any single phase motor.

You can easily in just 1 hour or less convert your motor over to solid state starting switch or potential relay to replace the centrifugal switch. Depending on how much you jog, that may solve your problem.

As SteveKW pointed out also, if your jog frequency is very high, your start caps may heat up.

PUMPDESIGNER

RE: cap start & run reversing single phase problem

Comment: The standard off the shelf motor will not have the required capability posted in the original posting.

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