Power supply failure

Hello group,

I'm not a frequent user of this group as the mill/router I use is a
bought in going concern, or at least was, it now has a burnt out
transistor in the power supply to the 3 ST GS-D200s stepper motor
drivers. So I'm looking for advice!
The mill is an Intelys F1000 made by Multisoft Robotique in France
(no website :-( )or email adress.
The stepper motors are Sanyo Denki 103G770. The supply transistor
has of course burnt off its markings. It is set to run at 39V by a
zener and 1k resistor and must be an NPN TO-220 type. But is it a
Darlington or just a simple one and what amperage? The motors are
2amp and only 2 ever run at once so I guess about 6 or 7 amps. The
stepper motor drivers can handle 2.5 amps each.

Any suggestions or actual knowledge of the device? Any suggestions
gratefully received!

John Brouwer