Millermatic 250 (1992) troubleshooting

admin

Good day to you all,I’m tempting my luck today on behalf of a friend.I wish to state first that I’m not a welder (nor do I have a machine to play around with yet) nor is my friend. I have a decent base in both electrical knowledge and electronic components. I’m looking out to helping him find and solve the issue/s of one of the welding machines he’s got to repair.His knowledge of both electronic components and electricity might be far ahead of mine, although he’s doing business in such field and I am not.Long story short, one of his customers asked him to repair a millermatic 250 machine as some of their welders noticed some issues with it, whenever the amp would be cranked up, it’d begin to stop welding either partially (intermittently) or completely and the said issue mainly occurred at higher amperage.The feeding gears are new, the wire is of the adequate thickness, no apparent damage to the motherboard and all capacitors were replaced and he even added 2 extras (for a total of 10).I believe he could do some R.E. and follow up all the pcb circuits and flow of the machine to eventually get to the issue but as of many of you might be well aware, that’s both a pain and a non profitable process.He had the chance to get his hands on some interesting tech manuals over the years but this one is missing and wherever there seems to be some interesting info, we get to hit a wall with incorrect data.He’s tried to contact Miller for the right manual but when you aren’t a certified repair tech with thousands spent on training of their machines...So here’s some specs and more specific info;MILLERMATIC 250 Serial# KC239955 (1992)Assembly# 151987Manual Required; TM-1308 (Not OM, nor 1308A+, the original 1308)The original manual doesn’t cover the electrical and circuit diagrams, and the info we got our hands on weren’t in-depth enough or simply not of the right revision, meaning some components weren’t the same.The schematics for KC227524 through KC289995 were D-151-990 (ours is 151-987 but I’m certain the data would be accurate) And the schematics he has are for a newer revision of the TM-1308 which are not accurate at all for our model (SD-184-318) which is for KH313867 and up.Ideas and suggestions are appreciated although I’m limited in what I can achieve as I’m simply a friend trying to help one and I don’t have experience with such machines unlike him. Although the puzzle is interesting.I believe he wouldn’t be closed off to the idea of possibly paying for access to those schematics (both the circuit diagram and electrical one)Any info would be of huge help! Thank you and have a nice day,-Mike
Reply:People with proper access to Miller service manuals risk losing that access if they get caught sharing it.  It's hard to imagine anybody taking that risk for someone they don't know...Check out my bench vise website:  http://mivise.comMiller Syncrowave 250DXMillermatic 350P with XR AlumaProMiller Regency 200 with 22A feeder and Spoolmatic 3Hobart Champion EliteEverlast PowerTig 210EXT
Reply:Originally Posted by G-ManBartPeople with proper access to Miller service manuals risk losing that access if they get caught sharing it.  It's hard to imagine anybody taking that risk for someone they don't know...