METHOD FOR CONTROLLING OPERATION OF ELECTRODIALYSIS TYPE WATER PRODUCING EQUIPMENT

摘要

PURPOSE:To control voltage by operating a titled device at a fixed current value untill the concentration of salt of a desalted water attains a prescribed value, at the time of starting-up an electric power supply, and measuring the electric conductivity of a produced water in the same manner as in an conventional method of operation control, except said start-up. CONSTITUTION:A circuit having a voltage-current controlling switch 6 and a constant current device 10 are installed between a rectifier 2 and an ammeter 4, and the switch 6 is changed to the current controlling side at the time of power supply, and an impressing current value is set to the current in normal operation or the current close to it perform the operation of a fixed current value. The electric conductivity of a produced desalted water falls with the lapse of power supplying time, but when said conductivity attains the electric conductivity in normal operation or the value close to it, the switch 6 is changed to the voltage controlling side to shift the operation to the voltage controlling one. By this operation, an excessive flow of electric current such as in the case of conventional method is prevented because the control at the time of start-up is switched to the constant current control.