I have successfully converted a both a Lincoln CV-400 and DC-400.
I recently landed a Miller DeltaWeld 451. After looking at the schematic, and some of the other conversions floating around here and on the internet, I deduced that IF it was going to work, it would actually be a pretty simple conversion.
I did the conversion per the attached schematic, which is identical to the CP-300 conversion schematics that others have used, at least on the transformer side, so I figured that it would work.
Well, it doesn't work, and part of the reason that it doesn't work, I think, is because I'm not getting 240V across the middle transformer, and I cannot figure out why.
In the schematic that I attached, I get 240V(ish) across A-B AND E-F when I probe them on the back panel. However, I was only getting around 11.5V across C-D when I probed it. At that point, I only had 200MFD of caps in there, and I thought that was the issue, possibly, because it was supposed to have 256MFD. I added another cap, getting it to 250MFD, and the voltage went UP to 14V now, but it still won't weld.
The funny thing is that it will actually "weld" at times, but only for a 1/2 second or so, and then it quits, but most of the time when I pull the trigger, all it does, it just heat up the wire, and sometimes will actually melt the weld, but not weld.
What kind of voltage should I being seeing across that connection? I'm making the assumption that it should be 240V. I've checked all of the connections, and it appears that 120V is going to the cap banks, AND coming out, BUT when you test across the two, it is only the 11-14V.
I have a good feeling that this thing should be convertable, but just haven't gotten there yet.
Any ideas what I should try next, or what this issue could be with cap bank, or the voltage, etc????
Thanks!
I recently landed a Miller DeltaWeld 451. After looking at the schematic, and some of the other conversions floating around here and on the internet, I deduced that IF it was going to work, it would actually be a pretty simple conversion.
I did the conversion per the attached schematic, which is identical to the CP-300 conversion schematics that others have used, at least on the transformer side, so I figured that it would work.
Well, it doesn't work, and part of the reason that it doesn't work, I think, is because I'm not getting 240V across the middle transformer, and I cannot figure out why.
In the schematic that I attached, I get 240V(ish) across A-B AND E-F when I probe them on the back panel. However, I was only getting around 11.5V across C-D when I probed it. At that point, I only had 200MFD of caps in there, and I thought that was the issue, possibly, because it was supposed to have 256MFD. I added another cap, getting it to 250MFD, and the voltage went UP to 14V now, but it still won't weld.
The funny thing is that it will actually "weld" at times, but only for a 1/2 second or so, and then it quits, but most of the time when I pull the trigger, all it does, it just heat up the wire, and sometimes will actually melt the weld, but not weld.
What kind of voltage should I being seeing across that connection? I'm making the assumption that it should be 240V. I've checked all of the connections, and it appears that 120V is going to the cap banks, AND coming out, BUT when you test across the two, it is only the 11-14V.
I have a good feeling that this thing should be convertable, but just haven't gotten there yet.
Any ideas what I should try next, or what this issue could be with cap bank, or the voltage, etc????
Thanks!
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