Tom, I have to disagree with you this time. it is a 600V 3PH motor, and those Chinese combo machines are much more difficult to find a correct flange mount motor to replace it. [sidebar] For some reason most of those Chinese flange mount motors, like the ones on the PM1440G and most of the mills use some kind of weird non-NEMA profile and faceplate spec. Replacement motors for them cost a lot more. A bunch of guys have just finally got a motor for a fellow on HM that has been dead for a year. it cost double what a NEMA Baldor would have cost, but the fitment was wrong.
And is not a recommended thing to use a 240V VFD and put a transformer on the output. So this one is overpriced at 4000$. It is a project machine for an electrical wizard, not a home machinist.
Given that it has power feed motors and a coolant motor as well I would just run it at 600v. Its not rare to find a 600v transformer - far and wide more rare is 480v. In fact what I finally got is 600v to 480v (!)
Its a large mill - clearly not for everyone. I do think the 600v already depressed the price. But lets be honest for $4000 it would be a total steal.
A lot of home shops have rotary so adding a transformer is not an issue.
And by far and wide I am not electrical wiz. If you changed the machine from 600v to 240v its not just the main motor, or side motors (that very likely are 600v) its all the relays and breakers. You would need to rip most of the electrical panel out. Lots of work. Way easier to just plug transformer there.
Oh and given that it is horizontal - vertical combo I would not be shocked if it had two main motors. One for each spindle.
A small transformer at auction will run you 100 - 200 CAD.
I have no experience with VFD to transformer input - but a 10kv 240-600 transformer is quite large (microwave size) so I would expect resistive loads issues, Even with 5kv one. I only know that small extra loads do not seem to anger the VFD - like running resistive loads up to 50w, which is light or coolant pump or control transformer. The 600v to 480v 5kv transformer is tiny - size of a toaster oven.