I'm trying to add a solenoid to a gasless welder, iv added a euro torch all ready but I'm struggling with the solenoid.

The control board is 12v, iv tried connecting the solenoid to the return from the mig trigger and connected the neutral of the solenoid to a GND pin on the board but when the solenoid is connected is stops the mig from working.

Would using a relay off the mig trigger be a better idea and fit a PSU for the solenoid?

The little transformer doesn't Show a amp rating so I'm unsure if the solenoid is pulling to much it's ment to be rated at 0.40ma so I wouldn't of thought so but Unsure

The mig trigger is the bottom right connecter

 

1> Yes a relay is required - don't want to switch solenoid current by handle trigger.
2> Separate power for solenoid probably required as well. Solenoid inrush current sure seems to flatten built in supply - bad idea.
I'd measure the solenoid current profile and size a supply to hold the solenoid. Then add a big capacitor to feed the inrush.
Recommend doing all this stand alone, Then install on welder.

 

Thanks for the advice I'll make up a little PCB and give it a go