I have a century wire weed welder 225 amp. As soon as I flip the power switch the wire feed motor goes on full speed and is not adjustable. This happens with the trigger switch disconnected. I checked the the wire feed speed adjust and its ohms vary as I adjust the knob, as it should. I feel sure that there is a problem with the small board that these are connected to. The board consist of several components but I suspect that what I believe is a two prong transistor (ASI MJ900 8712) is the problem. Anyone know if I am on the right track or should I look for something else.

SOURCE: hobart 135 wire feed sped control problem

you have a resistor down, first check the resistor on the centre pole then those going off to the two other pins

SOURCE: I have a century wirefeed 225 amp welder that goes

sounds like a component is over-heating, this would possibley be located on a power resistor attached to a large heat sink, try the set again, when it goes into high speed, detach the plug from the wall socket, taking extream care, gently touch the power resistors for high temperators, these normally run hot so the faulty one will be abnormally hot, be extreamly aware of the large capacitors, they will be fully charged and will give you an awfull belt.

SOURCE: My Century 130 Mig welder,

any 110 male end will work just make sure the plug is rated for 20 amps at least, 30 preferred