Single phase reverse electrical genious required

Well my motor is fubar .Its a complete waste of money and none of this tech works . Have brought 3 phase kit and inverter none that worked and was electrifying tried to electricute me rubbish company wuld not put it right .

I brought this kitty motor worked fine and just wanted to relocate switch wired it up as it made sense worked fine for 5 mins before I connected it up on the bench in reverse and foward . I put it in lathe and it ran another 5 mins it started smoking then shorted out power righ through to the house. . Just believe its an utter waste of time and none of this works.

Hi Martin,
I think that motor is beyond economic repair. When you get a new motor wait until someone tells you how to connect it up to the reversing switch rather than just trying to connect it just using your intuition. It looks like the centrifugal switch did not disconnect the start winding when the motor was up to speed. As it worked in one direction you must have wired it up to the reversing switch incorrectly.

Les.

Martin

If you look in my photos ( click on photos under my name) you will see an album there called "Myford Reversing" - there are some pictures there of the reversing switch and the way that this is connected to the motor. Note that the reversing switch should NOT. be the means of stopping/starting the motor - this should be achieved via NVR starter which will ensure that , in the event of a power cut, the motor will not restart when power is restored. (and you have your fingers in the works!)

I echo the comments above advising you get professional assistance with the task - this is NOT a case for "poke and hope" - help might cost a few bob but it might save your life. Stay safe.

Norman

Edited By NJH on 27/04/2017 00:05:22

Every time I see the title of this thread in the listings I want to say "Sure: I'm a reverse electrical genius - will I do".

Hi all am staying away from 3 phase the stuff i brought was crap and from a crap company. the trouble with my kitty motor was the wires were not id'ed and even an expert would have possibly blown it . I am looking at these are they with roller bearings and reversable . With regard to NVR I have earth leakage and trips right town through to shed

https://www.machinemart.co.uk/p/1-5hp-single-phase-4-pole-motor/?da=1&TC=GS-010210434&gclid=CJa26oDEz9MCFQmdGwodZiAMEQ

Thanks for looking

M

Hi Martin,
You can't blame the kitty motor. If you had asked how to connect the motor up there are quite a few members that would have asked you to do a few simple tests with a multimeter to identify the start and run windings and how the centrifugal switch was connected. We would have also probably asked you to do some tests on the Drummond reversing switch to confirm that the connections are the same as a Dewhurst reversing switch. (Although the Drummond and Dewhurst switches look the same from outside you can't just assume that the connections will be the same.) You should also have a proper motor starter switch (which provides the NVR function and also has thermal overload trips) on the input side of the reversing switch. If you buy another motor then don't just connect it up and hope that it might be correct. At least post a diagram of EXACTLY how you have wired it before applying power and wait until a couple of members have conformed that it looks correct. They may still need to ask you to do some tests before being certain that you have done it correctly. I still think its better for you to ask how to connect it rather than just guessing.

Les.

Les,

I have asked, and posted images see above see above in relation to connecting this unit we are on page 4.

I think the problem lays in the kitty motor not being completely reversible having a pulley on each end was really a give -away in hindsight. If you look at the picture I posted you will see it burnt the thinner windings not the thicker ones everything was good in one direction until I tried to reverse. Thinking about it I left it running in forward some time whilst I was clearing up a workshop and all was good in this direction. I have now disconnected it all and am looking for someone to supply a non-chinese motor in my area that they will connect up with my wire and switch. I presume a rewind is no longer possible or available at an economic price?

M

Edited By Martin Newbold on 02/05/2017 17:45:27

Hi Martin,
From what I have heard it will cost more to have the motor rewound than buying a new one. Now you have one end removed from the motor it should be easy to remove the other end to look at the centrifugal switch if it has one. (As far as I can see you never identified the ends of the windings and if there was a centrifugal switch) Iven though it will not help now it would be interesting to see the centrifugal switch and how it is wired. I suspect that it will be in series with the start winding. I suspect the motors that Machine mart sell will be of Chinese origin. You don't say why you want to avoid Chinese motors. The original single phase motor on my Chester DB-10G lathe was probably Chinese and never gave any problems and the Tec three phase motor I fitted has never given any problems.

Les.

Hi Les, I would never buy chinese motors again. The crap one was as you indicated which tried to electrocute me despite wire , inverter and motor being sold by one crap firm I have lost in all confidence with that .

I rang two companies and found out rewind would cost £300 I have opened up kitty motor it has no centrifugal switch. I have watched two videos on youtube with a man rewiring a large motor It is interesting how they took it apart . I stripped mine right down and have started digging at the black windings. It is evident that they only run in four coils I presume in series. I have noted two breaks in the copper wire that runs in these inside the outer larger windings . I am unsure which is the start windings the red and black are on the larger windings which occupy the majority of slots in the field coil windings.

I also note that there was no insulator apparant between the coils i dont know why this is perhaps it was a cheap motor.

Edited By Martin Newbold on 03/05/2017 19:30:19

Hi Everyone have done a little more cleaning at one end in an atte,pt to understand what is here I still dont know if these wires in these colls are wired in series does anyone know?

Whill start on other end and see what that is like

Are these coils usually insulated by .3mm mylor card or thicker?

Ah its called nomex paper

As this motor was beyond economic repair at a specialist i was quoted £300.00 I have started tearing it down as the only blackened coils where the 4 set and not the larger set . I have worked out each slot hold 70 wires a piece . I am unsure how to turn a metric measurement to a wire guage. Two of the coils of 70 wires are longer than the outside ones.

I started teasing the wires apart slowely with a small electrical screwdriver . With theseseperated I could cut through the middle of the coils with a wire cutter . The scew driver was then hammered along the slot of the melted mylor this removed it from the slot so the wire strands could be pulled through with some waterpump pliers . The condition of the motor without these wires seems good . I am unsure if I can put it back but the utube fella in india made it look easy so will attempt try and get parts. It will be a learning experiance anyway.

Have finished removing the wiring which ws burnt and broken from the motor. It still needs cleaning up and I need to locate a source for the nomex paper does any one have any experiance of this . I note they make two types sticky and non sticky. Is there a benefit in using either type?

Edited By Martin Newbold on 09/05/2017 21:44:45

Martin

I see that you have been mucking about with this motor since June last year - time to give up maybe? Get another motor and get on with USING your lathe!

N

I agree with the previous two posts. The original switch may have provided a method to control the power to the start winding but with your lack of electrical knowledge I don't think you are capable of working out how the original switch works. I also do not think you are capable of rewinding the motor correctly as you do not seem to work out how to connect things. You just seem to swap wires around hoping that it will work.

Les.

Read up about the labours of Sisyphus before you start rewinding that motor.

Hi everyone and thank you for your comments. There is no centrafugal switch in this motor at all just a temperature switch which was between the two coils. The coils that are left read a good impedance and seem to be good .

Frances am unsure what insulation there was there between the coils but am aware of nomex being used in other rewinds. In addition some people on youtube are reusing motor wire in motrs and other application quite successfully so I am unsure why you state it wont be reliable

Les there is an instruction booket in the switch I brought . You have told me on two occasions that there is a centrifulgal switch which there is none. further more you said "You just seem to swap wires around hoping that it will work." . When did this happen ? Further more if i have a lack of electrical knowlege it may be because no one else here has any either, as no one chose at the time to point out anything was wrong with my wiring. You started this rant without even looking at the circuit diagrams I posted so I do not know why you are being offensive . When you dont know me. I thought ths forum was here to help people.

Read up about the labours of Sisyphus before you start rewinding that motor? can you provide a link please?

The spindle ad electrics is here there is no centrigugal switch: