[keebler303]

I recently bought a new lathe and I am working on getting it running. The DC spindle drive requires 460V 3 phase. I only have 230V 3 phase. The lathe has a transformer in it which is currently setup as an isolation transformer. 460 in and 460 out. The transformer is constructed from three separate transformers which are wired together. The attached schematic shows the existing wiring, how do I determine which wires I need to change to get 230 in and 460 out? It looks like there are 2 windings on the primary and its just a matter of series vs. parallel but I'm not sure how to go about determining which ones to connect.

Thanks for any help
Matt

[Al_The_Man]

Is there no terminal notation?
Al.

[keebler303]

Unfortunately, no. There are some color coded aluminum bands crimped onto some of the wires, but only the wires on the primary which connect between phases. The three sets of wires connecting between phases are red-red blue-blue yellow-yellow. The wires going from the top of each primary winding to the bottom of the same winding have no identification, only a black wire coming out of the winding. It looks like it has been worked on by at least one hack electrician. Some of the connections are just the wires twisted together and wrapped with electrical tape.

Matt

[keebler303]

To follow up...

I got it figured out. Each phase of the primary is comprised of two windings. They were in series originally. I cut all the connections loose and figured out which wire was what, then reconnected them so the windings were in parallel. I tested it out first using single phase 120V, then hooked it up to the three phase once I was fairly confident it wasn't going to blow a breaker.

Matt