Ancient single phase electric motor - reversing the rotation

[Barry White]

looks good to me do bear in mind Marvos advice

Quote "

• Start up of the motor should be crisp and you'll probably hear the centrifugal switch operate with a click almost instantaneously. If it's slow to start or there's humming/buzzing then disconnect immediately.
• When power is disconnected it should coast slowly to a stop and you'll hear the centrifugal switch operate when the rotation speed gets low.
• If the motor has a running current marked on it check the supply with the motor running using a clamp on ammeter. I'd think the running current should be around 50% of the stated value if there's no load on the motor. If the actual run current is greater than or almost equal to the current stated on the motor there's a problem and disconnect quickly before the windings get burned. "

 

[AndrewB]

reassemble it exactly as it came apart and just reverse the black and the red wires that go to the windings to achieve reverse rotation.

Hang on - I'm confused now. Mykey said swap blue and yellow - the circuit with the switch in it. ?
What have I misunderstood ?

 

[Barry White]

No Marvo said move the main winding (red and black) I said move the start winding (yellow and blue ) only one needs to be done or the motor will not reverse But any one swap should work

So both are correct just choose any one pair to swap looking at the picture you swapped yellow and blue so it will be ok to try now

 

[AndrewB]

Phew ! OK cheers. And I'll follow Marvo's safety advice as well.

 

[AndrewB]

Sorted ! Purrs like a kitten. And clockwise.
Mykey, Marvo and Lucien thanks for your help. If there was such a thing as a virtual pint I'd buy you one each.

if only I could remember what it was I wanted to drill.

 

[Marvo]

Great news, glad it's running. Happy drilling

 

[Barry White]

Always nice when someone listens and comes back with good answers for the questions asked. Knew we would get there in the end. Hope you learned a little too and give yourself a pat on the back for an excelent effort.
Please keep visiting the forum.

Cheers myke

 

[AndrewB]

Hope you learned a little too
Please keep visiting the forum.
Cheers myke

Certainly did learn something - and re-affirmed my belief that anything is fixable. It amuses me that to start with my expectation of success was pretty low yet in the end it was just 'swap two wires'.

I will be back - trying to think of other electrical problems for you gurus to solve. I've got some serious welding to do shortly but when I crank up the amps the breaker in the garage trips - so I'll need advice on CBs with different trip characteristics.

I wish I could give rather than take but all I've got is two bits of electrical trivia for you - seeing your sig Mykey 'Old electricians etc' well Heinrich Hertz's wife is buried in the village where my Dad lives and recognising the significance of the name he organised a proper grave stone for her.

Second thing is a bit of a teaser for Lucien - his Electrical museum would have been an excellent home for this




Unfortunately I gave it on permanent loan to a USAF museum last year.
The data sheet explains what it was for.

Regards

Andrew