Newbie seeking help regarding contactors please :)

[robinson16v]

Hello people, I'm Mark from Barnsley and I'm in need of some help, I am new here and not sure how this forum works yet so please bare with me and feel free to correct me if I am wrong!

Anyway, What I'm actually here for....

I have a Murex Tradesmig 160 mig welder that I bought recently as spares or repairs due to the no arc fault which turned out to be the contactor. Anyway I bought a replacement contactor and have had help off of some of the guys on the mig-welding forum but still no avail.
At it's current situation, the machine turns on, feeds wire and the gas relay operates but the contactor doesn't pull in, If I push the contactor in manually the gas solenoid clicks but pulling the trigger on the mig gun doesn't pull in the contactor.
I have tried to follow a schematic that is available to view on Murex's website and as said above have had a lot of assistance from the guys over at mig-welding forum, But thought I would try here to see if anybody can shed some light, Or if local enough even come and have a look?
Thanks in advance.
Mark

 

[Bobster]

Can you post a link to the wiring schematic?

 

[robinson16v]

Can you post a link to the wiring schematic?

Sorry for the delay in replying!!!

The schematic can be found here http://www.murexwelding.co.uk/manuals/other/Instruction Manuals/Tradesmig 130-160-230-240.pdf and you want to scroll down to the TM160 wiring diagram (some of it is upside down I'm afraid)

Thanks for the reply.

 

[Richard Burns]

It looks like relay RL1 on the PCB is non functional (assuming you have checked that the switch contacts in the gun do close when pressed), whether this is the relay not working or the circuitry to it I am not sure.
This relay appears to control the power to the contactor operation and gas solenoid valve.

 

[sysrq]

Have you tried to simply measure the control voltage on each relay or switch and rechecking dc resistance of every coil, look for loose connections and conductors if yes then there might be something really weird going on.