© KEMPPI OY MINARC 150, 151 / 0531 – 73.4.1. EarthingIf possible, always fix earth cable clamp directly on the welding piece.1. Clean connection surface of earth clamp from paint and rust.2. Connect the clamp carefully so that contact surface is as large as possible.3. Finally check that the clamp sits tight.3.4.2. WeldingSee also 3.1. Welding processes and 3.4. Welding selections. Note! It is recommended that you trywelding and rate of welding current first on something else than the actual work piece.You can start welding after having made the necessary selections. Arc is lit by scratching the weldingpiece with electrode. Length of arc is regulated by holding electrode tip at a suitable distancefrom welding piece. Suitable arc length is usually about half the diameter of the electrode corewire. When arc is lit move the electrode slowly forwards tilting it to appr. 10-15° pulling angle.If necessary, adjust current value.Shielding gas is used in DC TIG welding. Your dealer will give you advice on choosing gas andequipment. Open the gas valve on the TTM 15V TIG torch. When gas starts to flow, arc is lit bylightly scratching work piece with the tip of the tungsten electrode. When arc is lit, its length isregulated by holding the tip of the tungsten electrode at a suitable distance from the work piece.Move the torch forwards from the starting point, usually in appr. 10-15° pushing angle forwards.If necessary, regulate current rate. Stop welding by lifting the torch off the welding piece and byclosing the gas valve on the torch.Note! Always fix the gas cylinder so that it stays steadily in upright position either in specially madewall rack or cylinder trolley. Always close the cylinder valve after having finished welding.3.5. STORINGStore the unit in a clean and dry place. Shield it from rain, and in temperatures exceeding +25 °Cfrom direct exposure to sun.4. MAINTENANCEBe careful when handling electrical cables!In maintaining the unit, take into consideration the rate of use and the environment it is used in.When the unit is used properly and serviced regularly, you will avoid unnecessary disturbancesin use and production.4.1. DAILY MAINTENANCEPerform the following maintenance daily: Clean electrode holder and TIG torch’s gas nozzle. Replace damaged or worn parts. Check TIG torch’s electrode. Replace or sharpen, if necessary. Check tightness of welding and earth cables connections. Check condition of mains and welding cables and replace damaged cables. See that there is enough space in front of and back of the unit for ventilation.