Help! Wire Feed Button Broken!

[capri]

Hi. I have a sip migmate 130 turbo with a wire feed problem, the mig work perfect on all the preset buttons and still welds but the wire feed button is does nothing when you turn it up and down, iv checked the pcb and all looks fine and no loose wires anywhere, any ideas, cheers lee

 

[shenion]

Do you mean the knob that controls the wire speed?

That would be aboard issue, most often the drive transistor has shorted. That will cause the speed to always be fast.

 

[capri]

yes the wire speed knob, what does the drive transistor look like

 

[shenion]

The transistor is usually mounted to an aluminum heatsink.

 

[capri]

thank for that, il have a look