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Induction Motor Wiring? Answered


I've recently bought a Clarke Induction Motor with these specs:

1 Phase
2 h.p.
1.5 kW
1330 rpm
50 Hz
9.4 Amps

Capacitor Details:

50 micro Farads
450 V

I have been looking all over the internet on how to wire it up to go into 240V mains (UK) but I can't find a thing. In the terminal box there are 6 terminals labled V1, V2, U1, U2, W1, W2.

A brown wire connected to U2 and a blue wire connected to W2 lead off to the capacitor.  A red wire connected to V2 and a white wire also connected to W2 leads off into the motor. Another red wire connected to V1 and another white wire connected to W1 also lead off into the motor. Nothing is yet connected to U1.

Please see the pictures which make this a lot clearer.
(I have removed the capacitor from the blue catch for the photos)

I have looked all over the internet and there seems to be no mention of anything. I basicly need to plug this into mains (therefore 3 wires, live, neutral and earth - obviously earth goes to the motor casing) So which wires go where? Also, the website of the shop that I bought it off said that a 10-16 Amp starter is required. What does this mean/do? Can you just plug it into the mains without this starter.

It is probably obvious that I am somewhat of a rookie in motors!

Thanks very much in advance for any help!


You can make a crude rotary phase converter using capacitors sized for the motor aswell. Gets expensive over a couple hp

Sorry. I meant Delta not Y

Type in 3 ph Y Delta wiring and look at the images.

6 terminals.

Its a 3 phase motor right?

Wire it in wye configuration and use a variable frequency drive or a rotary phase converter

Hello - we have the same motor and have no idea how to wire this up - have searched around the net but nothing, did you find out how to wire this up? Any help will be very much appreciated as we are stuck.

Hi the Live and Neutral connections should go to the two posts with Brass straps one to each either way round is fine as is an AC motor with start winding and centrifugal switch. The Terminals on the motor are Labelled for three phase motor wiring in Star or Delta so not really appropriate to single phase application. Just wired one of these motors up so I had to check my theory.

Here is the standard motor hookup.

As the motor starts to spin up to speed the cut-out switch disconnects the 50 uF AC capacitor from the start coil winding for the duration and the motor only runs on the coil winding 1-2....

The second pic shows a cut-out switch and the AC capacitor.

Still looking, got to go now.


Thank you for that, it's the wiring up to the plug we don't understand, live and neutal, where do they go ?

A dual voltage motor has two windings that are in parallel for low voltage and series for high voltage...

Sorry, I'm not familiar with the UK symbol designations.

BTW be sure to click each pic to see the entire image !


Also notice (1) & (4) is always tied to the main.

A different capacitance is used for the starting coil if it is a large motor.

Background FYI the starting winding and capacitor is used to provide a phase shift to begin a rotating EMF that starts to pull a rotor up to speed.. The start winding is usually low resistance, high current and would usually burn up if left on too long...


6 years ago

Since it didn't come with a wiring diagram ( sloppy shipping clerk )
I would temporarily lift the jumpers and capacitor wiring and Ohm test
the windings to try and make sense of the wiring.

Those jumpers are usually designed to wire coils in parallel or series for two different supply voltages.

Often the jumpers go horizontal for one voltage and vertical for the other voltage.

Usually they ship, setup for the higher voltage to avoid smoke at first

The stater is a box that limits inrush current and usually puts some
current limiting devices in series with the motor either manual or automatic one to five steps.

The motor running current is 9 amps, that means it could do momentary 90 amps with a mains unrestricted start.


Ok thanks very much I'll have a look into the testing tomorrow.

Would it be possible to run the motor without a starter for testing/ brief use while I search for one? (Also, I have a spare switch: would this be adequate (obviously it is not a starter but just as a switch for the motor?) - similar to this one http://www.axminster.co.uk/axminster-axminster-kjd17-switch-prod824645/)

You might have to reset some circuit breakers and get a new switch.

Are you saying that you definately need a starter and that the switch is not adequate?

All that can happen is popping a circuit breaker.
And a low cost switch might weld shut on the second try.

Nothing that inscrutable members are deterred by :-)

Who knows maybe you will find a  no-load start will work seven out of
eight times without tripping a circuit breaker.


Good idea since the motor manufacturer's web said you needed
to use a starter.

However would it work just directly connecting it to mains (eg house circuit breaker may trip)?

I will buy a starter soon but I am not able to at the moment...

Oh right, so the worst that could happen if I plug it straight to mains power (UK) would be that it may trip my house circuit breaker if there is a current overload? Then I would know that I need a starter?

I've done lots of electronics but never gone into motor territory - So I'm somewhat of a rookie! :-)
Thanks for your help so far!

Unlikely to be multiple voltage tapped for us - its 230 all the way.

I've had a look through that and other similar things: I understand the concept of the motor operation, but none of the PDFs go into much wiring detail.

Thanks very much anyway!

The diagrams refer to your motor - a multi meter should allow you to sort out which connection is which and then you can connect it up.

I enjoyed the 24 pp PDF on induction motors by Rakesh Parekh
of Microchip Technology.

There is an error in fig_3 ( dead short ) probably a drawing error.


Clarke is a brand of "Machine Mart" Try ringing them or going to your local branch.


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Ok thanks very much. I've contacted Machine Mart and Clarke via email: hopefully they'll reply with a manual/wiring diagram of some sort!

Also, look inside the terminal cover - the wiring diagram is often there !

Don't worry - I've scoured the motor all over to see if there is any sort of wiring diagram! The most information given is that of the nameplate (info I've given in my first post)