If it is 3 phase it could be a 4 wire WYE 3 legs and a neutral / ground.

The motor should have 3 wires of the same color (White) and one green
or Black.

If it has two white a green and a black it is a 220 across the white
and black neutral green safety ground.

If you have a plug on it that would also help us.
If you are talking about the plug numbers / letters. Means maximum not
how used.

I have seen 220 in a shop on a 5 lug plug. That plug had the lug sizes
and it exceeded need.

I used to use 5 plug 200 amp a pin and 3 phase 5 wire. Neutral and
Ground. Coffee can (2 pound size).

Martin

On 1/23/2018 7:57 PM, Bill wrote:
Bill wrote:
Â*I have an appointment to go inspect it!Â* : )



The serial number of the lathe under discussion is only 19 away from a
"known" Oliver 51-B registered at vintagemachinery.com.Â* That one was
"purchased off of craigslist from a gentleman who had purchased it from
a school" (this hints at its history).Â* Small world.

The bottom of the plug says, very nearly,Â* 20A, 250, 3.0 ... I believe
it isÂ* 4 wire 3-phase (is this consistent?).Â* Of course who know how
many times the unit has been rewired in it's lifetime.Â* The current
configuration was really too convoluted for me to understand.Â* I could
not see the motor since it was hidden away inside the unit.Â* The person
who allowed me to inspect it got irked that I even unplugged it.Â* The
electricity was "not available" for me to turn the unit on. It was set
up with a switch in a box.Â*Â* I'm leaning away from it (not being in the
need of a new big project), but you folks have been successful in
talking me into stuff before! ; )Â*Â*Â* Although it comes with a box of
parts, it's not like you can just run out and buy parts you want. I
believe it was made in 1931.

Bill

I'm allowed to "ask questions" and he said he'll "get them answered".
Are there any good questions I could ask?Â*Â* A guy who lives a few doors
down from me has a similar lathe in his garage and I have never seem him
use it. It would probably be simpler for me to go over and make him an
offer!Â* ; )