| 摘要 |
PROBLEM TO BE SOLVED: To perform the maintenance of an inverter, without stopping the line for a long time. SOLUTION: A first power supply system which supplies a motor 20 with power through an inverter 50A from a commercial power source 10, and a second power supply system which directly supplies the motor 20 with power from the commercial power source 10 are prepared in advance, and in the inverter 50A, the fault-judging means 56 judges whether or not the fault has occurred, when the first power supply system is performing the power supply. In the case that the judgment result of the fault occurrence is obtained, the power supply system to the motor 20 is switched from the first power supply system to the second power supply system, by operating switches 57a and 57b. |
