| 摘要 |
PURPOSE:To control the water level stably and to control the number of operated pumps reasonably by concurrently setting the number of operated sets of front and back pump groups in accordance with the feed water flow quantity and also by individually correcting the number of sets in accordance with the water level of each water reservoir. CONSTITUTION:When the feed water flow quantity Q is increased to reach Q32, a set number setting circuit 12 increases the set number setting value N1 from one to two, and likewise increases from two to three when Q33 is reached. Contrarily, when the flow quantity Q is decreased to reach QT3, the value N1 is decreased from three to two, and likewise is decreased from two to one when QT2 is reached. On the other hand, when the water level H1 is detected by a water level meter 5 and the water level H1 is increased to reach A, a set number correction circuit 9 makes the correction set number DELTAN1 to one, and contrarily if the water level H1 is decreased to reach C the correction set number DELTAN1 is made zero. Accordingly, the standard set number is set by the common set number setting circuit 12 for pump groups 3, 4 of front and back water reservoirs in accordance with the feed water flow quantity, and the set number is further corrected in accordance with the water level change, thereby the water level can be stably controlled. |
