Help with lathe motor capacitor

I suspect it may be only running on the start coil only with one of your swaps.

Search on cap start and induction run motors, you will get wiring diagrams

It should reverse if you swap the connections of the capacitor where it meets the run coil and the start coil where it meets the run coil.

Measure the resistance across both motor bn to bl and also r to bk, the lowest resistance is the start coil if you disconnect the cap that one should go high resistance.

You will need to take the back plate off the motor, where you should find the centrifugal switch. Leave the switch wiring alone but look at the cap wire colours and see what it changes to, one leg will go to the switch on the end plate ignore that one.

Edited By Dave Halford on 27/03/2021 19:39:38

Thanks Dave, I'll see how I get on, be a shame to buy another motor if I can suss this one out.....

As so often happens, the fault may be a simple one, IF you have the test gear and know how to use it. The best plan may now be to strip the non drive end off and check the internal wiring and the centrifugal switch. If the C switch is sound, the insulation is good, and the windings have not been cooked then there is every chance that the motor can be got working.The first thing is to assertain which starting circuit is being used, as there are several.

Having twice in the last 3 months seen a type of motor wiring diagram that I did not know existed at first, to be told I was wrong when the poster had shown said diagram and it's operation was obvious because I had seen a motor of this type apart still counted for nothing in some's eyes. The fact that the diagram was also published in the Model Engineers Handbook by Tubal Cain still counted for nothing. It has been said by some that giving advice to an unskilled man on the subject of 240V electrics is to put said mans life at risk in this brave new world we live in. All I can do is offer advice and hope that common sence will prevail, or if you are not to far off and can travel I will test and if possible fix it. Good luck Noel

Thanks Noel, I'll get my meter on it to suss out the circuit, ive wired the motor to a NVR switch.

I'm in morecambe in the NW