Migmate 130 Turbo Circuit Board

[smiff]

I have a migmate 130 Turbo which i bought new back in 88/89. It`s been a good enough machine for my needs & has seen some action over the years. I went to use it last week & the wire feed stopped. Looks like a resistor on the board has burnt out. Every thing else works. The board is MIG 01 IPF. The burnt resistor is inbetween the big silver pot & the diode. It`s the only resistor on the board, does anyone know the value of it as it`s burnt & cannot see the stripes?
Thanks

 

[Kat M]

I could pull the cover off mine and have a look, but mine's a later one (Feb. '05 by the dates on some bits inside.)

The thing I'd be concerned about is why that resistor has burned out. Resistors are selected (by competent designers) to comfortably handle the power they're expected to dissipate under normal operating conditions.

I'm not sure where this one is in the circuit but I'd hazard a guess that the power transistor may have failed (transistors have a tendency to fail short-circuit) and overloaded the resistor, causing it to fail.

I'd suggest replacing the transistor as well (if you have no means of testing it) just to be on the safe side; otherwise the new resistor may go up in smoke as well.

Cheers, Kat

 

[shenion]

The transistor is a TIP35C, I would replace it.

There is a crude schematic here that shows the values.