Hey Mark,

So far, all the replies have been about "the motor", and simply
rewiring it. I am not at all familiar with what else might be on your
Rivett lathe, but I think, as you do, that it will be more than just
the main spindle motor.

That said, I still think that the best advice is to change the taps
and terminals to suit the 240, but it won't be as simple as has so far
been stated, and maybe you should get some assistance from somebody
close by that can help, or at least be asking for a complete set of
wiring schematics for the model you have. It is quite possible that
in fact the "whole machine" can be switched form 440 to 220, and has
an internal transformer to do so, and that with a schematic you'll see
what wires have to go where.

Take care.

Brian Lawson,
Bothwell, Ontario.
XXXXXXXXXXXXXXXXXXXXXXXXXXXXX.




On Mon, 17 Apr 2006 17:20:52 -0700, Eric R Snow
wrote:

On 17 Apr 2006 15:45:17 -0700, "Mark Main" wrote:

When I open the power panel on the end of the lathe I see the 3 wires
for the service power... but those wires hook into what looks like a
fairly complex power panel (I think it's the original Vari-Drive), and
from that it leads to the motor. I've never rewired a motor from 480V
to 240V.

I would prefer doing this the simplest way possible and so wiring 240V
would be great if I knew how to do it. Thanks.
Greetings Mark,
We need the motor data to help you. Someone here should be able to
tell you how to connect the motor for 240 volt operation. If the motor
is dual voltage then it makes sense that the control electrics will
also work with either 240 or 480 volts. Anyway, if you have 240 volt
service, then it will be lots easier and cheaper to build a 240 volt
rotary phase converter and change the internal motor connections. It's
not like you need to remove the motor windings and have it re-wound.
The motor will probably have 9 wires that can be connected two
different ways for either 240 or 480 volt operation. A common wiring
configuration is having the wires numbered 1 through 9. For 480 volt
operation the wires would be connected thusly: 6+9, 5+8, 4+7, with
wires 3, 2, and 1 connected to the power. For 240 volts the
connections a 6+5+4, 9+3, 8+2, 7+1, with the power again connected
to wires 3, 2, and 1. Of course, since this is a three phase motor,
swapping any two of the three power wires will reverse the motor. I
bet someone here has the actual wiring specs for your lathe.
ERS