Centroid Community CNC Support Forum

Good afternoon,

I have watched the training video on YouTube and the instruction there is to ensure the manufactured leg of the power is on L1 of the main disconnect switch. I noticed my original hook up seems to have it in the middle terminal (see photo), L2? The Z phase, i.e. the manufactured one, is connected to the white wire).
The voltage to ground from the manufactured leg is higher than 120v.
My questions are what are the terminals? The switch is not labeled. Is L1 the one on the right or the left?
My second question is did I damage the system running it this way?

Thanks,
Mike

The generated phase is not clean and best used for motor run only. The other 2 phases are used for all electronics including relays, etc. I don't know your machine, but I had problems on a 16x60" lathe when the factory diagram was incorrect and the generated phase was being supplied to relays on a non-CNC machine.

I would suggest tracing the wires out carefully and making sure the generated leg only goes to the motor and not any electronics.

Identify which two legs, coming off the bottom of the rotary disconnect switch, are feeding the transformer that is immediately behind and below it.

Hook your clean utility legs to those two. Hook your wild leg to the remaining one.

The 2nd and 3rd terminals from the left seem to be feeding the transformer. I get a connection check on them with my multimeter when the disconnector is switched to the on position and the two input lines on the transformer are touched. That would indicate the left most terminal is the line to connect the wild leg to.

The voltage to ground from the manufactured leg is higher than 120v.

This is common on many three phase power supplies but if you measure line to line you will see a different voltage.

Wild legs were never intended to be used as a power source to ground, only line to line!

Dave C.