Miller 200 Fan Questions

[RonG]

Picked up a Miller 200 Mig to replace my Lincoln 180. It is a 1987 model. Seems to work well but the cooling fan isn't turning on with the main power switch. Should it be on full time or does it kick on as needed? I am in the process of cleaning up the machine and havent really welded with it yet.

[M J D]

Fan on demand

[RonG]

Fan on demand

Thank you very much..now to learn to weld

[M J D]

Thank you very much..now to learn to weld

I would check your electrical hookup inside the welder. There is a 200 volt tap and a 230 volt tap. With it set to your corresponding line voltage the factory parameters chart will be very close.

[RonG]

I would check your electrical hookup inside the welder. There is a 200 volt tap and a 230 volt tap. With it set to your corresponding line voltage the factory parameters chart will be very close.

Will do. Thanks

[ToolFanGeoff]

Ron, I have a MM200 that is older than yours - so check that this is the same for yours. My MM200 fan runs all the time the machine switch is turned on. Check out this thread on the Miller site:
1979 MM200 Millermatic 200 Fan Motor Repair - Miller Welding Discussion Forums (millerwelds.com)

I hope it helps.
Geoff

[G-ManBart]

Ron, I have a MM200 that is older than yours - so check that this is the same for yours. My MM200 fan runs all the time the machine switch is turned on. Check out this thread on the Miller site:
1979 MM200 Millermatic 200 Fan Motor Repair - Miller Welding Discussion Forums (millerwelds.com)

I hope it helps.
Geoff

I have had a number of MM200s and some had full-time fans while others had fan-on-demand. The manual for a machine made in 1987 shows fan-on-demand so if he got the year right, he should be fine.

[guajilloweld03]

Check the capacitors and verify they are not bad. When they go bad they will cause the rectifier to heat up and trip TP2 or TP3. While your at it check the diodes.

From research TP2 is 105 degrees to open and 125 degrees to close.

TP3 is 150 degrees to close and 180 degrees to open.