Converting Telwin 180/2 Turbo to Euro torch

  1. Willyswelder New Member

    Messages:
    4
    Location:
    Norway
    Hello. I just found out that my trusty Telwin 180/2 Turbo needed a new torch. I ordered a Twin 15, which was supposed to fit my machine. The old torch had just one wire. The new had two. One long and one short. The gas line fits, but I can not seem to figure out where to connect the cables. Been trawling the net, with no luck. Hope someone can help. Thanks
     
    • 20200416_124829.jpg
    • 20200416_124845.jpg
    • 20200416_124853.jpg
    • 20200416_124912.jpg
  2. a111r Member

    Messages:
    888
    Location:
    London
    Welcome!
    Essentially this is same model as my old Sealey 195. One wire connects via terminal 7 on the PCB, the other to DC +ve on the bridge rectifier.

    The old torch would have shorted the single wire to the torch gas block / valve (dc +ve), whereas your replacement only contains a micro switch to join the two wires.
    Diagram is here:
    https://www.mig-welding.co.uk/forum/threads/sealy-supermig-185-pcb-repair-help.53483/
     
    Parm likes this.
  3. Willyswelder New Member

    Messages:
    4
    Location:
    Norway
    Thank You! I am a total newbie. Where is the bridge rectifier?

    Thanks
     
    • 20200416_164218.jpg
    • 20200416_164227.jpg
  4. a111r Member

    Messages:
    888
    Location:
    London
    It's bottom right. One of the plates has the thick torch (DC +ve) wire connected to it, this is the one you want.
    upload_2020-4-16_15-50-33.png

    See if you get any other responses, as I could be wrong about the 2 wires!
     
  5. eddie49 Member

    I am sure that that is correct. Originally the switch in a single-wire torch would make contact with the brass block/swan neck, which is the positive welder output. Now having two wires and a real microswitch, you still need that positive rectifier output to correctly drive the relay logic on the PCB.
    [ In this 2-wire torch situation, you have the option of making the torch negative to use no-gas flux-core wire, but the PCB will still get the correct positive signal from the trigger switch.]
     
  6. Willyswelder New Member

    Messages:
    4
    Location:
    Norway
    Thank You very much! As i found the #7 terminal is the one that originally goes to the torch, and as I found out there is a free terminal on the bridge rectifier.

    This seems to be correct then? See picture.

    Best regards, Lars
     
    • 20200416_204614.jpg
  7. a111r Member

    Messages:
    888
    Location:
    London
    Not easy to tell from the photo but I think that's the 'wrong side'. As in dc -ve. That's going to the inductor (like a big transformer) then on to the earth lead.

    You need to tap into the top bolted dc +ve connection, or any free spade on it. I could be wrong, blame my eyes...
     
  8. eddie49 Member

    Lars, yes, that is correct. In the centre of the rectifier there is a heavy steel bar that is bolted to the black cable, going to the torch. There is also a thinner tab, on the same central bolt, which has a soldered connection to the blue circular component ( a spike suppressor ), and finally two red wires. That is where you need to connect the 2nd thin wire from the Euro torch.
    [ The negative, as mentioned by a111r, is the U-shaped strap linking the two outer plates of the rectifier. It is bolted to the solid winding wire of the inductor, which sits on top of the main transformer.]
     
    a111r likes this.
  9. Willyswelder New Member

    Messages:
    4
    Location:
    Norway
    It worked! I plugged it to the terminal mentioned. Thanks for all the help! Tomorrow I finally get to start welding on the Brewing table .
     
    a111r and eddie49 like this.
Advertisements