M G Electrics (Colchester) suds pump wiring.

[Jim BeagleyParticipant @jimbeagley46363]

[Jim BeagleyParticipant @jimbeagley46363]

I’ve recently acquired a suds pump which I want to fit.
The back of the motor says

380/220
440/250

its written like that but it’s one slash.
It also says 3phase and 0.122/.22A

Now although it says 3phase, looking at those voltages, I’m thinking it’s both 3P or 1P, star or delta. Does that make sense?

It has terminals numbered 1-4 and 5 wires from the motor itself – 2 distinct windings perhaps?

It’s currently wired up with an external capacitor, and a 13A plug and it runs ok but the wiring is old. When I opened up the motor case to take a look it’s clear that the cap wires have got pretty hot in the past.
So, shall I just repair the wiring and carry on using single phase with a potential issue, or convert it to 3 phase which means quite a lot of hassle in the then required 3P connection and switch?

anyone got any thoughts and even better, a terminal diagram of this motor?

Cheers
Jim

[Stuart BridgerParticipant @stuartbridger82290]

Hi Jim,

That's exactly how my suds pump is wired. Motor run cap to give the third phase. Very easy way to run a low powered 3 phase motor off a single phase supply. No need to change. I would tidy up and leave as is. I think there is a terminal diagram under the cover of mine, but I'm not too enthused to poke about down the back of the lathe to dig it out.

[DC31kParticipant @dc31k]

It is a good motor: it will run happily on high voltage 3-phase, low voltage 3-phase or single phase (with capacitor).

Are you quite sure on the five wires? It should be six, one for each end of the three motor coils. When I took mine apart with a view to rewinding it, I do not remember the star point being buried. This was an old one with the switch on the top of it.

Most modern motors you see have six-way terminal blocks as standard, with brass bus-bars, to allow star or delta connection.

I think the only thing different in this motor is the terminal block itself; it only has four connections, for star operation. If you change it for a six terminal block, you will have all options open to you.

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