18 – MASTER MLS™ 2500, 2503, 3500, 3503, MASTERTIG MLS™ 3000, 3003, 4000, 4003 / 0606 © KEMPPI OY4. MAINTENANCEWatch out for mains voltage when handling electric cables!Degree and circumstances of machine utilisation should be taken into consideration when planningproduct maintenance. Careful use and preventive maintenance help to avoid unnecessary productiondisturbances and breaks. Check the condition of the welding and connection cables daily. Do notuse damaged cables.4.1. REGULAR MAINTENANCE4.1.1. Every sixth monthsNOTE! Disconnect the plug of the machine from the mains socket and wait for ca. 2 minutes(capacitor charge) before removing the casing plate.The following maintenance operations should be carried out at least every sixth months:• Electric connections of the machine – clean any oxidised parts and tighten any looseones. NOTE! You must know the correct tension torques before you start repairing theconnections.• Clean the inner parts of the machine from dust and dirt e.g. with a soft brush and a vacuumcleaner. Do not use compressed air because there is the danger that the dirt is packed evenmore tightly in the gaps of the cooling profiles. Do not use a pressure washer.Only an authorised electrician may repair the machine.4.1.2. Service contractKEMPPI service workshops make special service contracts with customers about regularmaintenance. All parts are cleaned, checked and if necessary, repaired. Also the operation ofwelding machine is tested.4.2. TROUBLESHOOTINGPower On light is not lit.There is no power in the machine.• Check mains fuses, replace blown fuses.• Check mains cable and plug, replace defect parts.The machine is not welding properly.There are plenty of spatters during welding. Weld joint is porous or power supply is insufficient.• Check welding settings and adjust if needed.• Check gas flow and gas hose connection.• Check that earth clamp is properly fastened and that earth cable has no defects. Change theposition if necessary and replace defect parts.• Check welding torch cable and connector. Tighten the connection and replace defectiveparts.• Check the consumable parts of welding torch. Clean and replace defect parts.• Check mains fuses, replace blown fuses.