Schaublin 125-CNC retrofit.

Personally, I'd just buy a servo and rip oit all the crap on the spindle, you can get a 5kw spindle and drive on Alibaba for $400 shipped or less. That'll give you what you're after for a lot less hassle. Pull out the pulley system and all and just direct drive. Get a 5000rpm servo that should give you way more cut powe than you have.

Pick your excuse :
1/ That requires more effort than my inherent laziness allows
Everything is already in there.

2/ I don't see a deal like that. The best deal offered here for a 5KW servo and driver from AliExpress is at least €1000, so will cost more like €1500 delivered, with tax and customs.

3/ I only have 16A feed at 400V. The required supply varies, but those 5KW servo drivers seem to require supplies which can peak above 20A.

But it is basically what Schaublin did on the follow on 125-CCN model. Since my collet closer limits the spindle to 3000rpm, a 1:2 reduction to the spindle would work, as those servos seem to be 6000rpm.

One thing I didn't notice in the vid or the thread discussion is that there is a separate manual for the braking module.  It's referenced on page viii (Part G - 11) of the VFD manual.

The braking module manual shows a "T1" and "T2" connection on the module.. but those aren't shown in the main VFD manual.

Based on the diagram, I suspect those need mains power to 'activate' the braking module.

I'm sure there are some parameters to change as well, but this might be a possibility.  Maybe have a look?

And yes...dogshit manuals.

 

Those are the thermal overheat switch, which with that wiring will cut power to the main VFD in the case that the brake module overheats. To test it, that connection is not necessary.