I have a Thermal Dynamics Pak Master 50 (not an xl) that after diagnosing using the service manual, appears to have a bad logic board. Since the unit and all it's internal parts are obsolete and no longer sold, I'd like to try to repair the board. I've contacted Thermal Dynamics and have requested the LLD (logic) board schematic or even a block diagram, but it has to be submitted to see if they will release it to me. So I thought I would ask my fellow Welding Web'ers to see if anyone out there has one they would share. Any help would be appreciated.
Reply:So it looks like nobody here has a schematic for the board and TD still hasn't got back to me. Here is the problem this cutter is having. When turned on, the fan comes on, the AC light is on, the temp light is green, the PIP light is on, and the gas light is on and gas flows for 20 seconds. When the trigger is pulled, the gas flows and the spark gap assembly and the torch have a quick small arc and then there is nothing. According to the service manual and based on the tests they have, the LDD board is faulty. Has anyone else had this problem and were able to fix it? Usually if I have the schematic, I can fix pretty much anything. Anyone with any ideas or if you have a working LDD board you would sell, I would appreciate your help. Thanks
Reply:Wish I could help Steve. Sorry.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!
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o you have 120VAC between J18-1 and J18-3 when the torch is activated during and after the brief blip of an arc at the spark gap assembly and torch?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:Backing up half a step, does the DC indicator come on within2 seconds of activating the torch?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:Originally Posted by duaneb55Do you have 120VAC between J18-1 and J18-3 when the torch is activated during and after the brief blip of an arc at the spark gap assembly and torch?
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id you check for 15-18VAC between LDD board J1-9 to J1-7 and from J1-9 to J1-6?Apparently, voltage in this range at these locations indicate a faulty LDD board.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:What's your air pressure set at?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:Originally Posted by duaneb55Did you check for 15-18VAC between LDD board J1-9 to J1-7 and from J1-9 to J1-6?Apparently, voltage in this range at these locations indicate a faulty LDD board.
Reply:Originally Posted by duaneb55What's your air pressure set at?
Reply:Also thought I'd mention that if I bypass the logic by jumping TP21 to TP3, I get DC voltage and a continuous arc at the the spark gap assembly.
Reply:I'm actually not familiar with the machine and I was just going down the troubleshooting list throwing things out in case you missed something.Are you using service manual 0-2444?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:Originally Posted by duaneb55I'm actually not familiar with the machine and I was just going down the troubleshooting list throwing things out in case you missed something.Are you using service manual 0-2444?
Reply:Update: Thermal Dynamics sent me the schematic for the logic board. I've got to say the customer service tech that I was communicating with, was awesome. He gave me several things to check while we were waiting for the schematic from their outside server. Ended up finding a bad resistor which led to a bad optocoupler. Just waiting for parts from Mouser. We'll see if it fixes it or if there is a continuing line of failed parts. Keeping my fingers crossed. If anyone needs a copy of the LDD board schematic, message me. Thanks Duane55 for your ideas. I appreciate your help.
Reply:Steve B.Were you able to get your LDD board working? Could you send me a copy of the LDD board schematic? My PakMaster 50 has the exact same symptoms as yours. Thanks
Reply:Wow that’s exactly what happened today about my Pak master 75 xl plus.Had this good machine 22 years and STILL same original whip on her. So please inform me on what and where to get replacement parts please.I hope you’ll read this soon,as I’m always using it .Thank you and Happy Holiday’s
