Hi Glen, you may be interested.

(a comment to those who missed my previous posts, I am converting my
welder from CC only, to CC and CV as well as selectable voltage range,
with hopes to make it into a plasma power supply also).

After a little test run, I am putting together what will become the
final rectifier and controller. I connected it with half of the
secondaries connected as Wye (which, as I know, makes too much
voltage).

After a lot of messing around, I am finally able to properly control
OCV with a pot. That was a very happy moment!

http://igor.chudov.com/projects/Weld...r/dscf0253.jpg
http://igor.chudov.com/projects/Weld...r/dscf0254.jpg

My plan for tomorrow is to put together a rudimentary control panel
(on/off, voltage and current control pots) and connect rectifier to
welder outputs. Maybe even test some stick welding, in 3-4 days.

After that, I will try to make a reconnector to select between
paralleled delta at 66 VAC, and sequence Wye at 220 VAC, using five 24
volt contactors.

i