I was given a huge old 1hp Black and Decker bench grinder that is quite old. It will take a 10" wheel and turns at 1800 rpm. This thing must weigh 75 pounds or so.
The motor is three phase but only has six leads. They are not numbered and I am not sure how to hook this up for low voltage. The wiring is cloth insulated and each wire looks like a different color but some are hard to tell what color they are.
I have heard of six lead 3ph motors but have never wired one. I hope someone here can "lead" me in the right direction on how to hook this up.
All of the six lead motors I am familiar with are connected in a Y configuration for high voltage and Delta for low voltage. I would recommend taking it to an electric motor shop and let them hook it up.
If not you can try this. BE EXTREMELY CAREFUL.
Take an ohm meter and find the leads that have continuity. There should be three pair. Temporaly label one pair T1 on one end and T4 on the other. Label the next pair T2 and T5 and the last T3 and T6. Now connect T1 to T6, T2 to t4 and T3 to T5. momentarily connect power. If the motor runs normally, all is fine. If don't start or runs slow, swap numbers on the first coil(ex exchange T1-T4). See if it runs. If it won't run normally, try reversing T2-T5. Try again. If it won't run reverse T3-T6. It should be good on one on one of these connections.
One other possibility, if it is a single-voltage motor, is that it is wye-start, delta-run. In either case, you first have to figure out which leads are pairs as Charles described.
Here is a sample wiring diagram:
Here is a page with links to other common motor wiring connections:
The motor was connected like the diagram showed for high voltage so it was easy to tell what were leads 1,2&3. I got the coil pairs sorted out going by what Charles posted. Got it running on the first try! [img]smile.gif[/img]
Thanks again for the help