| 摘要 |
PURPOSE:To suppress the pressure reduction to the min. by starting and stopping a plurality of compressors in the prescribed order and providing a start instruction to other compressor instantly when start fails, in the captioned apparatus equipped with an effect waiting timer for preventing the hunting of control. CONSTITUTION:In an automatic controller 1, when the start and stop of three units of compressors 13 (additives are omitted) are controlled, the discharge pressure signal supplied from a pressure transmitter 14 is taken into a comparator 4, and compared with the pressure set by a lower-limit setting device 3. When the discharge pressure is smaller than the set pressure, an operation-unit quantity increasing signal is input into a start calculation circuit 5, and an increasing instruction is transmitted into an estimated start machine selecting circuit 7 during the time when a starting-effect waiting timer 6 is in time up, and transmitted as a count starting instruction into a trouble detecting timer 11. When the operation signal is not input into an operation confirmation circuit 10 within the set time of the timer 11 after the start instruction is generated, start anomaly is judged, and the reset operation of the timer 6 is suppressed.
|
