Mitsubishi Electric FR-A720-0.4K Instruction Manual page 9

4.31 Check and clear of the alarm history ............................................................ 383
5 PROTECTIVE FUNCTIONS
5.1 Reset method of protective function ............................................................. 386
5.2 List of alarm display ........................................................................................ 387
5.3 Causes and corrective actions ....................................................................... 388
5.4 Correspondences between digital and actual characters ........................... 401
5.5 Check first when you have troubles .............................................................. 402
5.5.1 Motor will not start ................................................................................................................. 402
5.5.2 Motor generates abnormal noise ........................................................................................... 402
5.5.3 Motor generates heat abnormally .......................................................................................... 403
5.5.4 Motor rotates in opposite direction ........................................................................................ 403
5.5.5 Speed greatly differs from the setting .................................................................................... 403
5.5.6 Acceleration/deceleration is not smooth ................................................................................ 403
5.5.7 Motor current is large............................................................................................................. 403
5.5.8 Speed does not increase....................................................................................................... 403
5.5.9 Speed varies during operation............................................................................................... 404
5.5.10 Operation mode is not changed properly .............................................................................. 404
5.5.11 Operation panel (FR-DU07) display is not operating............................................................. 404
5.5.12 POWER lamp is not lit ........................................................................................................... 404
5.5.13 Parameter write cannot be performed ................................................................................... 404
6 PRECAUTIONS FOR MAINTENANCE AND INSPECTION
6.1 Inspection item................................................................................................. 406
6.1.1 Daily inspection ..................................................................................................................... 406
6.1.2 Periodic inspection ................................................................................................................ 406
6.1.3 Daily and periodic inspection ................................................................................................. 407
6.1.4 Display of the life of the inverter parts ................................................................................... 408
6.1.5 Checking the inverter and converter modules ....................................................................... 408
6.1.6 Cleaning ................................................................................................................................ 409
6.1.7 Replacement of parts ............................................................................................................ 409
6.1.8 Inverter replacement.............................................................................................................. 413
6.2 Measurement of main circuit voltages, currents and powers ..................... 414
6.2.1 Measurement of powers ........................................................................................................ 416
6.2.2 Measurement of voltages and use of PT ............................................................................... 416
6.2.3 Measurement of currents....................................................................................................... 417
6.2.4 Use of CT and transducer ..................................................................................................... 417
6.2.5 Measurement of inverter input power factor .......................................................................... 417
VII
385
405