Connecting 240v inverter to 3 phase lathe Ask questions and find answers to many subjects relating to electrics and electrical work

[Bangui]

I have an old 3 phase woodturning lathe (Union Graduate) which I used to run, through an inverter, on single phase 240v supply. I purchased the lathe and inverter together. We have just moved house and in the course of the move the inverter wires were pulled out of the junction box of the lathe. I now have 4 wires from the lathe (red, red, red and green) and 4 wires from the inverter (Power plus VM 2.2kw) which are Grey, Brown, Black and Yellow and I have failed to match them up correctly! I assume the 3 red lathe wires are Live 1, 2 and 3 and the green is Neutral. Can any one assist in matching the inverter wires, please? Thanks, Don

[ericmark]

Likely green goes to yellow and they are earth but also could be neutral if there is a control circuit on lathe.

The three reds likely go to Brown, Black, Gray which is now standard colours for 3 phases. It may go backwards in which case swap any two reds.

Inverters for motor control often must have the motor connected and can be damaged if run up without the motor so I would be wary of running without three reds connected to Brown, Black, Gray.

Small motors are often run star on normal three phase supply (400v) but delta on an inverter (230v) so don't be temped to run on standard 3 phase.

A new inverter will cost around the £140 mark for that size of motor. Maybe there is something on inverter to give more information about it?

I am a little surprised there were not more connections? It would be normal to wire the inverter to the stop/start button as the inverters normally need to be connected at all times to the motor.

I have looked for details of inverter but have failed. The lathe easy enough to test with meter to find if green is earth. Seems likely but not so easy with the inverter. Yellow could be a control wire and I would hope there is some instruction with inverter?