The Steamboating Forum

My lathe motor burned up last week. It was a Nunming 1.5 HP and lasted 25 years.

I found a Baldor L1319M on ebay and got a good price on it. It looked like a close replacement. And that's the end of my electrical ability right there.

I still think that it is a close replacement but I'll be darned if I can figure out how to wire the new motor to the existing leads. That's what I would like someone to tell me if possible.

The existing leads came off the old motor like this:



The new Baldor has nine wires in the junction box. Two are unlabeled and joined together, and there are 7 other wires labeled 1,2,3,4,5,J, and 8.

The sticker on the junction box looks like this:



I need to know what wires from the new motor to twist together such that I can connect them to the four leads that my lathe has. Or am I going about this all wrong?

My lathe schematic looks like this:





I need to run 230V, single phase, with reversing.
Thanks in advance for your help, I'm dead in the water!


CannonFodder (Robert)

The wiring plate and diagram on your new motor are reasonable enough, but the wiring diagram for your lathe appears to be wrong somewhere. It looks as though it shorts the mains input at some switch positions. It would be a significant detective exercise working out what it really is, and I couldn't be 100% sure without checking using a meter anyway, so let's see what people familiar with US dual voltage single phase motors come up with. We don't have dual voltages available here in the UK as standard, but there used to be a few "split phase" motors around in the 1960s, which used a transformer to get +240 and -240 from the single supply. Dual voltage here normally means choosing delta or star wiring for three phase stuff.

The diagram on the motor is pretty straight forward - swapping leg 5 and 8 for forward or reverse. The motor plate will determine what "high" or "low" voltage is and then simply wire accordingly.

The wiring diagram for the lathe? That looks typical for Chinese equipment and I would not trust it very much. Often their manuals do not accurately correspond. i.e. try ordering a replacement part for one of their machines, guaranteed it will not be correct.

As RGSP suggests above, get a meter and start chasing down wires and run continuity on the motor control switch/contactors to determine how 5 and 8 can be swapped.

-Ron

Hello Guys,

Thanks for the responses, I think I have found a source for a closer-matched Chinese motor.

See you soon,

CannonFodder (Robert)