BP series 1 Boss 4 to EMC Gecko drive Power Supply retrofit

I recently acquired a working 1978 Boss4 Series 1 Bridgeport with the
Vram head. My shop runs on 480V 3phase, and I can't stand the thought
of throwing out a perfectly good power supply when I should be able to
use it!
In looking over the schematics
<http://keycoldstorage.com/BPsyswiring_pg4-113_small.gif> for my
Bridgeport, I find a power
supply <http://keycoldstorage.com/BPsyswiring_pg4-113_detail.gif>
style that I am not familiar with. In searching the Yahoo cam
group, as well as CNCzone, I was not able to find anyone who had
described using the existing three phase supply during a retrofit; but
much of that I liken to most of the users' desire to switch to single
phase given the opportunity.
In any case, this supply appears to have some sort of voltage
following or normalizing type circuit to balance the three phases in
DC. I have seen the secondary transformers described as both bucking
transformers and line reactors, neither of which I believe are
accurate based on the scematic. I could be completely off base,
correct me if I'm wrong. The truth is, I'm not against building a new
supply, but my dad is not for throwing away such "perfectly good
iron!" and I really don't care about speed for this machine. So the
question is really whether or not it is worth it to simply tap the
supply in a similar fashion to the original Bridgeport drivers (see
attached schematic), or to yank it and build anew? If I do use the
existing supply, where should I tap in to best preserve the new Gecko
202 drivers and my old Superior motors?
Thanks to all who reply!
edgar


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