snap-on minimig 180c live torch

[westwood3]

Hi,i am new to this forum and hoping someone could give me some advise as my wire is always live on my snap-on 180c and i have seen mentions of a relay but unsure how to check it and its location thanks mike

 

[chevy2]

Have a look here, i posted up all the pages from the minimig 180c manual,
http://www.mig-welding.co.uk/forum/threads/arco-lincoln-minimig-180c.29900/page-2#post-359147
By the way, welcome

 

[westwood3]

Have a look here, i posted up all the pages from the minimig 180c manual,
http://www.mig-welding.co.uk/forum/threads/arco-lincoln-minimig-180c.29900/page-2#post-359147
By the way, welcome

Thanks for that,had a look tonight at my welder and think the relay is located on the pcb but theirs two relays on their and the lower one looks like it may be my problem,on the forum you sent a link for you see a few replys on someone has put a picture a of a pcb and you see a clear relay at the top and at the bottom of the picture you see the edge of the one i am thinking is faulty and want to comfirm this is for the wire live cheers mike

 

[NotANormalCoder]

Main contactor that controls welding output, is located in the area beneath the wirefeed mechanism, just in front of the main transformer - remove the smaller side panel for access and you'll see a mass of wires going to/from it. Normally, when the trigger is pressed, the control PCB send a voltage to this, it energises (with a solid clunk) feeding power to the transformer. As it is controlled by a relay on the PCB (can't remember which), a fault here may cause it to energise as soon as the machine is powered up. If this is the case, you really need the PCB looked at by an expert. It may also be physically stuck in the ON position. Rare but not impossible with a very dirty machine. Worth looking at the relays, as if the one controlling the contactor has welded its contact shut, replacement may solve the problem. Otherwise it'll be a fairly complicated repair.
HTH Dave

 

[westwood3]

Main contactor that controls welding output, is located in the area beneath the wirefeed mechanism, just in front of the main transformer - remove the smaller side panel for access and you'll see a mass of wires going to/from it. Normally, when the trigger is pressed, the control PCB send a voltage to this, it energises (with a solid clunk) feeding power to the transformer. As it is controlled by a relay on the PCB (can't remember which), a fault here may cause it to energise as soon as the machine is powered up. If this is the case, you really need the PCB looked at by an expert. It may also be physically stuck in the ON position. Rare but not impossible with a very dirty machine. Worth looking at the relays, as if the one controlling the contactor has welded its contact shut, replacement may solve the problem. Otherwise it'll be a fairly complicated repair.
HTH Dave

Hi dave,
had a look dinner time,put pcb back in and on number 1 setting seemed to be ok and the single contact relay was moving as i would expect then turned it up to number 6 and after arcing and letting the trigger off it stayed live and i could see it was sparking inside the relay on the contact but if i keep dabbing the wire after at least five times the wire would become dead as it should be,cheers mike