Quote Originally Posted by Muzzer View Post
When they say reduced performance on single phase, it shouldn't be by much. The main difference is that the input current is shared between 4 rectifier diodes rather than 6. The dc voltage ripple inside is slightly higher but of no concern. It should work identically, with a slight (10-20%) reduction in S1 continuous power rating. I'd be interested to hear what derating they recommend.

I'd be surprised if you got anywhere near 7.5kW continuous shaft power on a machine like this. I'm guessing you bought this for low speed torque as much as anything, at which operating point the input power will be a fair bit less than 7.5kW. Personally I wouldn't bother with the expense of installing 3 phase when you could spend that money on more machine tools....
Thanks Muzzer.

Ive been quoted around £4500 for 3 phase. I am limited at this type of machine at current levels but it remains an option.

Yep, I was willing to take a chance on this setup and running it on Single Phase. It will certainly use all the current available to it but yes, 7.5 KW of actual cutting load is a lot. If the machine is sold to someone else, at least they know its capable if connected to a suitable power supply but for my needs, I doubt Ill ever need that.

The hardinge has a belt / pulley setup so I Can mess with ratios to get what I need but yes, generally low torque for materials that are hard or like thread cutting where you might be using slow RPM but need the torque.