FORCIBLE OPERATING METHOD OF SUB PUMP IN WATER SUPPLY DEVICE

摘要

PURPOSE:To prevent over rise of pressure of supply water, by temporarily carrying out combined operation within an allowable output range of an inverter at a time point where the operational characteristic point of a main pump transfers to a forcible operation starting point of a sub pump because of reduction of usage of water. CONSTITUTION:If the operational characteristic point of a main pump 1 transfers to a forcible operation starting point of a sub pump 5 because of reduction of usage of water during when the main pump 1 is operated independently by means of an inverter 10 while a standby pump 7 and the sub pump 5 stopped and the total input signal for the main and sub pumps 1, 5 is within an allowable output signal of the inverter 10, the sub pump 5 is operated forcibly in parallel. Here upon, the delivery pressure may increase remarkably, but since the pump is controlled such that the total input signal for the main and sub pumps 1, 5 will be within the allowable output signal of the inverter 10, over rise of the delivery pressure can be suppressed. Furthermore, a pressure detector 6 detects the pressure rise so as to enable constant control of the delivery pressure.