4 Wire motor

Hi All

Very happy bunny or was. Bought a second-hand Quron and started to get the hang of it.

Running fine switched off switched on BANG, Found the problem a washer had got into the motor and shorted out. Motor US

Fitted another motor ZP Motori Tipo 63 this had been running fine. But smart arse me wanted it to go in reverse like the old one, which it does but something is not right, gets very hot even with no load.

two green wires and two read come out of the motor and a single capacitor .

Have wired the cap into the two green got hot then wired it into the red still gets hot.

There is no centrifugal switch like the old motor.

Help please

Sounds like you have a permanent capacitor run motor. Running hot under no load is pretty characteristic of the breed. Excellent at their design job but not a general purpose motor. Ages back I fitted one to a pillar drill which eventually fried itself mid-way through a long series (50??) of fairly small holes (3/16).

Post mortem research revealed that this type of motor are a sort of "synthetic 2 phase" machine despite the single phase supply and very efficient at their design speed, load and slip angle. Unfortunately any change in slip angle as when running off load or with more than the design load rapidly upsets the synthetic 2 phase business so motor efficiency drops signifcantly and things become hot'n bothered. Often fatally.

A major application for these machines is driving continous or near continously running fans. Once up to speed the load settles very close to the design rating so the motor is happy, running all the time the extra efficiency relative to a standard single phase motor means smaller electricity bills. No centrifugal switch simplfies the design too making for a cheaper motor.

Clive

Thanks for the reply Clive.

Put the original wires back and tried it under load (connected to the Quron spindle) seems to run ok,not getting hot.

But now needs a little help to get started then runs fine ??? Depending which direction I "help" thats the way the motor runs.

I can live with this if it's not doing any harm???

Vernon

Hi Vernon,

Could you post diagrams of the way it was wired originaly when it "Worked fine". The way it is wired now (Needing help to start) and the way it was wired with the reversing switch when it ran hot. A diagram of how the motor that failed was wired to the reversing switch would also help understand the paths between connections on the switch in each of its three positions.

Les.

Hi Les

Been trying to draw the wiring but not having much luck, so will try and explain.

I have messed around with the wires that I cant remember how it was before

sorry. This what I have now.

+ in going to the cap and one red and one blue

- in going to the second red

other side of the cap going to the second blue

Do I need to be taken outside and shot ???

Hi Vernon,

I assume you mean live when you say + and neutral when you say - (+ an - are on DC supplies the mains is AC ) The way you have it wired could be right or you could have the windings mixed up. This is why I wanted to know how it was wired when it worked properly. I would expect the winding that should have the capacitor in series with it to be the winding with the higher resistance.

Les.