| 摘要 |
PURPOSE:To inhibit a supply-voltage drop in case of starting by starting the compressor on the low-speed operation side at rating in a short time and changing over the compressor to the high-speed operation side. CONSTITUTION:When an exciting coil 5 and a delay timer 8 are excited by turning a switch 10 ON, the winding circuit of a compressor motor 1 is fed from U1, V1 and W1, and the motor is started by the low-speed four-pole operation of series star connection. The delay timer 8 set at the retardation time of one sec or four sec is operated, and a normally closed contact 8b is brought to an OFF state and the exciting coil 5 is turned OFF while exciting coils 6, 7 are excited. The winding circuit of the compressor motor 1 is fed from U2, V2 and W2 at that time, and the motor is changed over to the high-speed two pole operation of parallel start connection. Accordingly, the supply-voltage drop in case of starting can bar inhibited. |
