Mains electric motor wiring.

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Matrosen

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I'm tearing my hair out here! I've got a Siemens electric motor from a washing machine that I want to use to power a micro lathe. The problem is that the motor has six grey wires plugged onto a pcb inside by spade terminals. they are marked thus

UB+OUT D1 D3

GND A1 A2 D2

I I I I I I (These represent the spade terminals)


The GND is obvious and I guess the A and the D represent the two speed circuits.
I've just wasted three hours of my life on Google and got nowhere!
Any help would be much appreciated.

Edit. The forum closes up the wiring terminal markings when I preview my post so I'll explain.
The UB+out and GND are ubove the first terminal, the A1 above the second and so on.
 
What type of motor is it? Can you see if the rotor is solid metal ie Aluminium and iron.(called a squirrel caged rotor) Has it also got a centrifugal switch mounted on the rotor,or has it got a commutator,ie brushes.
 
Personally I say forget it!
My lathe has a 0.5 hp 1420rpm "squirel cage" motor. I think you will find they are not expensive to buy. The speed is more or less naturally constant. It is also easily reversible, a reversing switch being fitted to the lathe. (The grey thing with the red knob)

Click:-
 
??? Squirrel cage with commutator, not possible its either one or the other. Has it got a centrifugal switch internally? I doubt if its got a commutator unless its quite old. ie a series type motor.where you have the armature in series with the field coils.Thats why its called a series motor.
 
The only washing machine motor I have had much to do with was a commutator motor. That I know because it regularly needed new brushes. (Like every year!)

Can you get the big difference in speed necessary for washing and spin drying using a squirrel cage motor?
 
As Vic says by forum its not easy to answer your question there are too many variables. some washing m/c motors are capacitor start and also have 2 sets of rotor windings,slow for wash and fast for spin.The old type of motor like Vic is talking about have a start winding on top of the run winding the reason being its not possible to start an induction motor on single phase, with a heavyish load,without a start winding.As soon as it gets up to speed the centifugal switch cuts the start winding out.Some motors use a capacitor instead.Have you tried ringing Siemens and ask for technical,you might find an obliging character.,
 
You refer to a micro- lathe. A 300 watt motor sounds fairly big for such a task. Washing m/c motors that I've seen are usually "down to a price" open framed jobs. A lathe can cover its motor with a generous coating of metal particles and swarf, in which case there could be fireworks. An enclosed motor has much to recommend it for a machine tool. Also, if it's a commutator type, the speed will vary markedly with load which can be a nuisance.
 
Thanks all for your help. Nedmin, you are of course quite right, it is not a squirrel cage. My reply before was meant to read "Not a squirrel cage but with a comutator" but as usual, my SWMBO was relating a conversation that she had had last night and was asking questions to see if I was paying attention!!!
VicS. This lathe really is a micro lathe. It's a Peatol and is supplied sans motor with a recomendation to use a washing machine motor of between 1/4 and 1/2 Hp. I used one in Britain but it was too heavy to bring in hand luggage with the lathe.
I will phone Siemens tomorrow and see how I get on.

For the Peatol website http://www.peatol.com/
 
The motor you have if it has a commutator could be almost anything. Some later auto washers have electronics to start stop and reverse the motor to get an agitation rather than the older style which used a synchronous or squirrel cage motor and various mechanical gearbox arrangements to get reversing agitation and higher speed spin.
My guess is that the design calls for an older style syncronous or squirrel cage motor which inherently run at a little less than 300 RPM or 1500 RPM.
To explain the AC field rotates at 3000 or 1500 RPM depending on the number of coils and the rotor (squirrel cage) tries to keep up. Max torque tends to be about 5% less rotor speed than the AC field. Of course in USA with 60 herts supply these speeds are 3600 and 1800 RPM.

A commutator motor as in an electric drill is easy to slow down but speed depends on the load so usually very high speed under no load (and noisy).

The squirrel cage motor in a washer usually has 2 windings one primary winding to provide a field and another sometimes mechanically offset or fed via a capacitorso that when power is applied the field is distorted to provide a start incentive to rotate in the correct direction. The second winding is often disconnected by a centrifugal switch once motor starts.

To explain in a single phase motor the field will move from N at top to N at bottom at 50 hertz. A bit like a bicycle pedal it needs to be started rotating to define a direction. So 2 windings. If one winding is reversed but not the other then rotation will be reversed. That is about all you can do to the motor to control it. I hope that explains a little. olewill
 
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