Raindrop counter and control system for irrigation systems

摘要

Disclosed is a raindrop counter and control system for irrigation systems which provides the quick detection of the presence, and subsequent absence of precipitation once it has first been detected. When applied to automatic irrigation systems and the like, the invention disables normal operation of the system by interrupting power to the irrigation valves during and after detection of precipitation. The control system includes sensitivity selections to electronically adjust the triggering threshold to precipitation, as well as a decoupled comparator network which compensates for background ambient light levels. Furthermore, the duration of sensed precipitation will determine the disable time period by reprogramming the output delay from a short to a long delay time period, if so desired. The time of the long delay is then user selectable to a plurality of time periods. The invention comprises a small outdoor probe, and a separate control and display unit that is capable of interfacing with a plurality of automated systems.