| 摘要 |
PURPOSE:To prevent an overcurrent by interrupting a power source to a rectifier after the prescribed time is elapsed from when a motor is stopped by the reset of an inverter, thereby reducing the variation in the voltage of a smoothing condenser. CONSTITUTION:A motor controller with an inverter 8 has a control substrate 1 which places a microcomputer, a protecting unit contact 3 for opening a contact due to the occurrence of a malfunction, a rectifier 7 and an inverter drive circuit 9, and drives a motor 10. In this case, the coil 5c of an electromagnetic contactor 5 for turning ON or OFF a power source is energized or deenergized by a signal from a microcomputer placed on the substrate 1 for detecting the opening or closing of the contact 3. Thus, when the contact 3 is opened due to the occurrence of a malfunction, it is detected by the microcomputer, and whether the inverter 8 is operating or not is decided. The microcomputer applies a control signal for stopping an inverter to the drive circuit 9 at the operating time to reset the inverter 8, thereby stopping the motor 10. Further, after the prescribed time by a timer, the contact of the contactor 5 is opened, the power supply to the rectifier 7 is interrupted. |
