Low Ocv's on 59 1450 rpm sa200

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I bought a 1959 sa200 that was already completely taken apart. The guy I bought it from was going to rebuild it and gave up on it. I completely rebuilt machine and matched up punch marks on rack and on exciter housing. The machine welds ok but not near like I want it to. At 1470 rpm I have 120 volts at plug-in but only 82 volts at lugs. Does this sound right?
Reply:no. should be around 92-98 ovcs but then again you can adjust them to perfection.
Reply:I guess the only way to raise my volts at my lugs and not change volts on my plug is to roll the rack?
Reply:Start by bringing the no-load speed up to 1550rpm.  1450rpm is full-load speed.OCV spec is 88-92 volts so you're only 6 volts off from minimum and the increased rpm should bring that in.  Auxiliary power voltage will likely exceed 125V but that's still well within acceptable.Also make sure the Fine Current control is set to 100% and confirm its resistance is 64ohms +/-.Last edited by duaneb55; 08-29-2013 at 08:32 PM.MM200 w/Spoolmatic 1Syncrowave 180SDBobcat 225G Plus - LP/NGMUTT Suitcase WirefeederWC-1S/Spoolmatic 1HF-251D-1PakMaster 100XL '68 Red Face Code #6633 projectStar Jet 21-110Save Second Base!
Reply:Thanks Duane, ill try that tomorrow. What is the max volts I can have at the plug?  I don't want to burn up a grinder or shunt coils.
Reply:Trying to find it but I believe Kaye Sellon once said keep it below 130V.  10% over would only be 126.5V.MM200 w/Spoolmatic 1Syncrowave 180SDBobcat 225G Plus - LP/NGMUTT Suitcase WirefeederWC-1S/Spoolmatic 1HF-251D-1PakMaster 100XL '68 Red Face Code #6633 projectStar Jet 21-110Save Second Base!
Reply:Well, haven't been able to find the specs in any SA200 information but the Classic lists "normal" no-load exciter output as 125-135V.I also found a posting where Kaye stated 90-94V for OCV but I know I've also seen 88-92V - just can't find it.  So . . .I shoot for 90V when tuning a unit which meets both the above ranges.Bring the high idle speed up to 1550rpm and see what the results are and go from there.MM200 w/Spoolmatic 1Syncrowave 180SDBobcat 225G Plus - LP/NGMUTT Suitcase WirefeederWC-1S/Spoolmatic 1HF-251D-1PakMaster 100XL '68 Red Face Code #6633 projectStar Jet 21-110Save Second Base!
Reply:Ok thanks I appreciate it. We'll see how it goes.
Reply:I have 88 to 92-volts in my notes from Kaye too.Don’t pay any attention to meI’m just a hobbyist!CarlDynasty 300V350-Pro w/pulseSG Spool gun1937 IdealArc-300PowerArc 200ST3 SA-200sVantage 400
Reply:Thanks for the "confirmation" CEP.  I was beginning to think I was imagining things. The Classic machine specs are 123-132VDC for the exciter output and 88-95VDC for weld output OCV (SVM134-A) but the Classic runs a slightly higher nominal high idle speed of 1600rpm vs. 1550 for the typical SA200.MM200 w/Spoolmatic 1Syncrowave 180SDBobcat 225G Plus - LP/NGMUTT Suitcase WirefeederWC-1S/Spoolmatic 1HF-251D-1PakMaster 100XL '68 Red Face Code #6633 projectStar Jet 21-110Save Second Base!