New mill, which motors?

[Doddy]

Genuine interest... why not a TVS/MOV device? (I can guess at tolerance/variance at the switching voltage - but that is just a guess).

[Muzzer]

Yes, usually the combination of the limited number of nominal voltages and the tolerance. They aren't too bad actually but you may struggle to find a voltage that is much above 36V but safely below the max allowable voltage for the drive. I'd be more confident in MOV than a TVS but that probably won't make much difference here. They are both deadly fast, so speed isn't an issue.

[Robin Hewitt]

Gosh I am out of date. Mind you, the power feed I am rewiring uses a DIAC for the speed control so I am not completely passed it

[Muzzer]

Yes, I remember them. Presumably used in the gate of a triac or scr, then. That dates the controller, as that threshold function has been built into triacs for many years now. I'd guess 1980s, most likely.

[Robin Hewitt]

1980's? Warco sold it as new

[Muzzer]

Perhaps an SCR drive then, as SCRs don't have a 30V threshold on them. But even so, the market for diacs is very limited these days.

What's it driving? Is it a triac or an SCR?

[Robin Hewitt]

SCR that's the beastie, my ageing brain has obviously succumbed to the barrage of transient ischaemic attacks.

Fortunately, I can still understand how the circuit works even if I can no longer name the individual components

[Robin Hewitt]

Motors and PSU have arrived, I wasn't actually expecting them before 10/1/21

Look great, comfortably heavy.

I read the manual and just when I thought it must be reaching the bit about the USB connection it suddenly stopped, repeated itself in German and ended.

Guess you aren't supposed to use that part

[hanermo2]

Good luck mate.

Upto about 100$ some steppers are ok for better stuff.
After that, ac brushless servos are the right choice - about 5-7x better by every possible measure.
About the same money, all-in.

Lets see how it works out for you.

[Robin Hewitt]

A bit late now, I am already compensating for my poor choice by printing lightweight handles