Ive found the ciruit diagrams of my machine and one that may be for yours. I can email it to you if you pass on your address.
Hi Cager,... I have an Automig 180MXE which has a faulty control board. If you still have the circuit for your machine I would like a copy if possible as it may help me decipher my version. Mine does not have the "Latch" function as far as I can tell although the front panel shows four options!
... I assume you have a copy of the Operating manual for the 180 MXE which is on the Migatronic website. Your cleaned up version of the main box circuit is much nicer than the version in the manual! The circuits of the various control modules are more difficult to come by. I now believe my unit (Type MPS STD Pt No 76116973) is functioning as it should.
... I am giving my eyes a rest from peering at the PCB trying to deduce what they are doing. For the record I have some information on the identity of some of the less common bits.The two FETs (1RF530)are the drive and brake devices for the wire feed motor. one of them is turned on to drive the motor and the other is turned on to short circuit the motor in order to brake it quickly.
The mode switch on my 180 MXE only has three positions in spite of the fourth position marked on the front panel doesn't provide the latch facility!
...the rather unusual switch appears to be of a type made by EBE in Germany (and possibly others) and is one of a range of different configurations of type SB20. If you need a new switch try Burklin.com. My switch is a 4P 3W version and has a detachable spindle which does not seem to be shown on the data sheet. The resistor networks are each made of four individual resistors of two different values. The Drive to the Gas Valve and main contactor is from the 24V supply switched by Triac(BT137) which is controlled via the opto-isolater. (K3021). Data Sheets on all the above devices are available on the net but if you cannot find them feel free to contact me. I hope to get back to the circuit tracing before long but don't hold your breath! Hope this is helpful
Colin