Thread: lectrick Motor Update

Hi Kev,

Good news, pleased to hear you'll be able to nail it back on the perch..

Regards
Ray

Great news.

I hate when you find out it was a simple fix that you could have done yourself.
Hopefully being something small it wont cost the earth and you can keep your bank account full so you can keep looking for a shaper.

Dave

mmmm ,yeah ,a nice shaper Im keeping my eyes open.

Kev.

From a post I made last year about a failing dusty, might explain the rocking/starting in alternate directions situation, particularly since they have diagnosed dodgy connections on the terminal block and starter switch contacts.

Single phase motors have two groups of windings, Run windings that are energised whenever the unit is powered up, and Start windings which are normally energised until the motor gets to about 70% of its rated speed.

A single phase motor normally will not start if only the the Run winding is energised, the shaft will generally rock a small amount in either direction. This occurs because there is nothing to tell the motor which way to run. In this situation the motor can often be flick started with a quick flick in the required direction, but this is not an option for a dusty.

The start winding is typically connected in series with a Starting capacitor and a centrifugal switch. The capacitor acts with the winding to temporarily introduce a second power phase to the motor, giving it a kick in the right direction. However the windings are arranged so that the current passing through the Start winding is significantly more than that through the Run winding. The centrifugal switch connects the Start winding and capacitor while while the motor is stationary or running slowly, and then disconnects it once the motor is approaching rated speed.

Mal ,
Thanks for the explanation ,had me a bit confused as to why it was doing the "double dance."
I guess with the dodgy terminal block and the connections the capacitor wasn't able to provide that "kick in the pants" to send it on its way.

Kev.

Well got the motor back today and nailed it back on its perch ,it's all good and I'm a happy camper.
Almost finished the job that was trapped in the vice for a couple of weeks.

Kev.

Good to hear your back up and running again. Did they look after you on price?

Dave

Good one!!

Originally Posted by Dave J

Good to hear your back up and running again. Did they look after you on price?

Dave

Didn't say how much or give me an invoice , but I have known the bloke for along time , I think he was just working on it it between jobs.
I don't think it will be a huge amount , basically he just put a new terminal block on ,having a look at it I could have done the same job myself if I had realised what the problem was.

It was worth having him look at it , I was prepared to have the thing re wound on my diagnosis.

Another douglas shaper went on ebay yesterday ,$477 ,or close to that price .I emailed him to see if he would put it on a pallet and freight it here ,but as usual the answer was no .
Looked well used ,but hard to see from the pics.

Kev.