I have a Denford Viceroy lathe with a 3/4 HP 3 phase motor. I also have an Altivar inverter with which I run another identical machine successfully.
The problem motor (dated about 1965) runs smoothly but at very low power, it will only start the lathe in lowest direct gear and you can stall it with a hand on the chuck. The three input wires connect to three wires inside the motor, no other wires/connectors visible. Am I right in thinking that the motor is wired in star configuration and is expecting 440V? Also, since no other connections visible, I'd need to dismantle the motor to find the star point, then re-wire?
I've trawled the archive on Google but I'm not sure I understand everything I've found.
Thanks for any advice. Richard