6-1 Inspection and Maintenance 6 Inspection and Maintenance *1. The life of the capacitor depends on ambient temperatures. Refer to the product life curve in Appendix-2. When the capacitor stops operating at the end of the product's life, the Inverter must be replaced. *2. Clean the Inverter periodically. Accumulated dust in or on the cooling fan or heat sink can cause the Inverter to overheat. 6-4 Inspection part Inspection item Inspection point Inspection period Inspection method Criteria Standard replacement period Meter Daily Periodic Main circuit Relay terminal block Check that there is no abnormal sound during operation.
3 Acoustic inspection No faults ⎯ Resistor Check that there are no large fissures or discoloration in the resistance insulation. 3 Visual inspection No faults ⎯ Tester Cooling fan Check that there are no abnormal vibrations or sounds. Check that there is no dirt or dust.*2 Check that the fan is mounted correctly. 3 3 3 Rotate manually when the power is off. Visual inspection Visual inspection Smooth rotation 2 to 3 years Control circuit Operation check Check the balance of output voltage levels between phases in single Inverter run. Check that there are no errors in trip detection and the display circuit throughout the operation of sequence protection.
3 3 Measure the phase- to-phase voltage between Inverter output terminals U/ T1, V/T2, and W/T3. Simulate the Inverter trip circuit output Ex) Use an external trip etc. Voltage difference between phases 2% max. Operates with no faults ⎯ Digital multimeter Rectifier Voltmeter Parts check (including PCB) General Check that there are no abnormal odors or discoloration. Check that there is no significant rusting. 3 3 Visual inspection No faults ⎯ ⎯ Capacitor Check that there is no liquid leakage or deformation. 3 Visual inspection *1 ⎯