We have a large CNC router with a 15kw water cooled spindle. The original drive on the machine was a Siemens Simodrive 611u. This is supposedly a very capable drive, but in this application it is/was only being used as an ordinary VFD. The drive failed and now I am trying to discern our best course of action. I know very little about these Simodrives and their abilities.

I have a quote to repair it for a little less than $5000 and replacing it with a refurbished unit from Siemens is about $1000 more.

That is a lot of money for little more than just a VFD.

I can buy a new Yaskawa V1000 drive and braking resistor set up for our spindle for about half that much (or maybe less.) Is there any compelling reason to stick with the Simodrive 611u? Or is there some reason that drive is so awesome as to justify it's price premium and I should stick with it vs retrofitting something else?

(PS our spindle is a 24000rpm 4 pole induction motor with, with no position feedback, so any VFD capable of 800+Hz, 30amp, 400v output could run it. I know the 800Hz requirement does limit options quite a bit, but other wise it isn't exceptional.)