H-K CP300 Conversion

First, I have successfully completed the H-K conversion on a CP250 TS, and it performed flawlessly. But, being it is really only suited for Spray Transfer, I've decided to let it go, and concentrate on my CP300.

OK, I've read through the CP200 thread numerous times, and ksimolo thread on his CP300 conversion, and e mailed Dave, who gave me some direction, but since we all know he's a busy guy, and I don't want to be a pest, I thought I'd throw a few questions out here.

I have wired the two outer coils as detailed, and calculated my approximate required capacitance to be about 116 uF (if that's correct?) for the middle coil. Jumpers are set for 460V configuration. Hooked it all up, and threw the power to it, and she isn't happy. It sounds like the transformers are fighting each other.

I determed all the brush holder assemblies, to keep the rectifier from having any possible influence, although the diodes all checked good @ .43V.

So, I pulled the connections at the Caps to ensure I had the outer coils as they should be, sounds great, nice quiet hum. OK, so I removed the jumpers from the outer coils altogether, essentially removing them from circuit, hooked the power wires that I ran TO capacitors, directly to the wires run FROM the capacitors, in my mind this should verify the center coil isn't junk, and my wires are landed correctly. I should mention, before this step, I thought my center coil was no bueno, so I megged the coil, all taps to each other, and all taps to grounding lug, checked out as good or better than the others, so I had hope once again! Anyway, I hooked the center coil up to power wires, no capacitors, and flipped the switch. Nice quiet hum all by itself.

Well, I think my coil is good, put the capacitors back in circuit, still only powering the center coil by itself, and it isn't happy at all. Voltage at the terminals is 179V to ground, 358V L-L, and current (measured with amp clamp) is 13A. Whereas current while hooked to just mains was .36A.

Upon Dave's recommendation, I checked all terminals for broken or cracked wires, and unfortunately came up with nothing.
He did mention that since it is a 200, 230, 460 machine, the voltage for the 208 would only be 125V (iirc), where I'm putting 240 through it. I don't understand the theory, and can't argue either way. I thought running it all tapped for 460 would keep the coils in their respective operating parameters?

Anyone able to help shed some light on what the heck is going on here? I've been testing this and that, checking and double checking things for a week, and am frustrated. I am wondering if it's something so obvious, I have blinders on and can't see the problem that's right in front of my face?

Here are the schematics from the inside of the machine, which match the downloaded manual received from Miller.

After more experimenting, I can drive both A & C transformers together, both A & B transformers together, and both B & C transformers together, without the capacitors in circuit. In all 3 configurations the transformers are quiet, nice soft hum.

As an experiment I connected only the C transformer through the capacitors, and it sounds just as the B transformer through the capacitors, noisy, sounds as if it is fighting itself. The C transformer also read same voltage and current readings as the B coil when connected to capacitors.

I made new wires to the capacitors and switched out the capacitors in entirety.

Bypassed the switch, to eliminate that possibility with no change.

I pulled the the wires from the terminal strip again, crimped and soldered 3 new ring terminals to the wires, with no change. The wires weren't cracked or broken, but you could see where the crimping too was run into the wire about 1/3 of the way into the wire. Also, as a note, the wires to the transformer on this machine are aluminum, with a thick varnish, varnish was removed with Emory cloth before attaching new ends.

Can anyone make any sense of this? Or explain the possibilities of what is going on? Or give me some more troubleshooting ideas?

Did you ever get this figured out? I am having the exact same problem with a dual voltage CP300. It sounded NASTY with the caps in circuit, and now just has a little buzz which still doesn't sound happy with only the bottom coil connected.

Honestly haven't worked on it. I did a cp200 for my dad with excellent results, ran it up to 275A pushing. 045 wire.

I hope to get back into it after 2 other Cp200's I have sitting here. One is mine, the other is going to either one of my brothers or uncle.