Electronic control device for a bistable solenoid valve with automatic low battery protection

Abstract

An electronic control device for a bistable solenoid valve, particularly for watering systems. The control device includes a power supply battery and a logic control unit, and provides low battery protection. A capacitor is set in parallel to the battery and a switch is operated by the logic control unit to effect, in a first operating position, charging of the capacitor and, in second and third operating positions, the application of control voltages having opposite signs from the capacitor to the solenoid valve for closing and opening the solenoid valve. The logic control unit is programmed in such a way that each request for opening of the solenoid valve brings about first the setting of the switch in the first operating position for charging the capacitor, then the switch is activated in the second operating position for closing the solenoid valve after a first preset time has elapsed following any previous closing control of the solenoid valve. The switch is then returned to the first operating position for a second charging of the capacitor and finally the switch is set in the third operating position to open the solenoid valve after a subsequent second preset time which is shorter than the first preset time.