The immediate first issue, is to determine weither you have the standard (in main unit) or one of the optional secondaries. For the sake of example, and the most likely probability, I'll assume that you have the STANDARD primary.
Notice that the SCR arrangement is much more 'busy' than a previous non-SCR version.
What they've done, is eliminated the variable-tapped secondary of prior CP series. This means that they're now using some OTHER variable, which is in this case, the SCRs. In SOME versions, the CP was left with hand-crank variable but fitted with (either factory, or aftermarket) SCR bridge, in which case, the ONLY thing those SCRS were doing, was cutting off output current in lieu of the output contactor.
In THIS case, the SCRs are actually being fired to CONTROL output power, and the cute little board labeled PC-1 is doing that job. It's actually looking at the output voltage (looks like wire 34 and 35) to accomplish this.
That being the case, jumping in and rearranging the secondary of that transformer to go Wye would be an Un-Wye-se idea...
But hey... lookie that primary- it is a Wye input, and has taps for 200, 230, and 460. This means we have some OTHER options, which says we don't HAVE to mess with the secondary, we just need to step an inch outside the 'box' and do some more math.
In this case, what we'd do, is recalc the coil voltages, and see if there's an arrangement that provides coil voltages of the 240v range.
In the original design, the CP-series used a 230/460Y input. My conversion severed the centerpoint, which makes each PHASE a 260v element... which I drove at 240v... 20v down on the primary. Swapping the secondary from Delta to Wye offset that, bringing secondary back into line. My conversion left the secondary windings set in series, because they were otherwise 130V coils (260/2=130 right?)
In the case of THIS transformer, there's also two sets of windings in each primary phase, and they have a 230v TAP, which has onelower at 200V. Because it is a Y configuration, when jumper is set for 460, each phase's primary sees about 0.6 of the full voltage.
simply put, if we utilize the 200v tap, and wire the coils in series using that 200v tap, we SHOULD be able to get each phase to be within range on the primary, and NOT have to mess with the secondary...
Get your pencils sharp,grab your calculators, and show your work... I'll be returning on Saturday morning to review this assignment and provide the suggested solution!
