Hello, I've been digging this forum for few days trying to find solution to my problem, but with no success. So I decided to register and find help. On the problem. I a came across Kemppi Mastertig LT250, this is the model that need external power source. As I learnt you can't just plug it and use it. For that reason I bought 200A stick welder to us as a power source and made the connecting cables. When I connect everything the machine starts and run with no problems. The problem is that the machine came with non standard torch. The original plug is removed and some king of plug and socket is in its place. The machine is working fine when it is set on touch and lift, but the high frequency start is not working, which is the problem. When I set the machine to HF and press the trigger the machine starts buzzing, but there is no arc jumping between the electrode and the work piece. If I press the button and the touch the metal piece, the arc starts, but this is basically touch and lift setting, and I need the HF to work properly. The guy who gave me the machine, brought it to the official service place in my country. He says that they made the HF by switching to original Kemppi torch and connecting the wires, but he couldn't what they've done exactly. The plug for the torch has only two wires going into the machine and this is from the factory, and I thick the are just for the trigger. Can any one give me idea of the problem? Thank you in advance.