Migmaster 250 no trigger response

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I bought this Migmaster 250 at an estate sale cheap, rolling the dice that I didn't have major issues. It turns on and the fan runs but there is no trigger response. I tested the trigger switch with an ohmmeter and it is working although I have a little resistance sometimes. I connected the switch wires with the switch disconnected, still no response. I pulled the covers and measured voltage where the switch wires connect, I have 15.5 volts AC rather than 24 volts. Is that the source of my issue? I tried to follow the wiring diagram but I'm not clear on where the 24 volts comes from, and not sure if I'm measuring things correctly. I'm an auto mechanic so I'm a DC guy. I put one lead on the machine ground to measure voltage. I don't have relays clicking or anything else happening when I pull the trigger.

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I forgot to mention that the switch for "Standard" or "Spool gun" just flops around, is there a way to bypass that to see if that is the issue?

[ccawgc]

Should be a machine diagram on one of the lower cover panels.
If not go to ESABNA and to the down load section and get an owners manual it will have it in it. or just google migmaster 250 manual and it will pop up in two places. there is a free manual library (manualslib)that allows down loads and some times it finds it at ESAB. With the diagram you can bypass the switch if it is bad.
Just searched it on Google and it took me to both. ESAB was at the top.
K2 and K3 have to pull in with trigger. These are the two small relays in plastic boxes.
After they pull in K1 the weld contactor will pull in and wire will drive.
If wire does not drive check wire drive pcb plug pins 5 and 10 to K2 relay contacts.
You should have 24 volts AC to the trigger show check the line voltage setting and your line voltage and make them match. sounds like welder is set for 240 and you are supplying 208 volts. Check the right lower side for a patch panel to adjust the voltage. if no patch panel look up by the line switch for a taped up lead marked 208 volts. switch the 230 volt lead for the 208 volt marked lead.
If K2 and 3 start buzzing there are two causes of this. Send me pm for deeper help.

[ronsii]

Also... don't forget to search this forum as there are several threads covering this machine here already..

https://weldingweb.com/vbb/showthrea...=migmaster+250