Rain gauge for measuring rain fall in an automatic weather station having an ultrasonic transducer for transmitting and receiving acustic signals into measurement chamber and programmable to determine water level in measurement chamber

A computer-controlled irrigation management system, including:

• at least one rain gauge for measurement of rain fall, each of said rain gauge including:
• a measurement chamber having an inlet port at one end and a drainage port at the other end, said drainage port being closed by a ball valve, said ball valve programmable to be opened at predefined events to release water collected in said measurement chamber,
• a funnel or collector adapted to receive rain fall, said funnel or collector opening into said inlet port, and
• an ultrasonic transducer for transmitting and receiving acoustic signals into said measurement chamber, said ultrasonic transducer being programmable to determine the water level in said measurement chamber and being programmable to allow calibration of said rain gauge based on the distance between said ultrasonic transducer and said ball valve surface,
• said system being programmed to provide operational control and collection of data from said at least one rain gauge.

An automatic weather station including:

• a rain gauge for measurement of rain fall, said rain gauge including:
• a measurement chamber having an inlet port at one end and a drainage port at the other end, said drainage port being closed by a ball valve, said ball valve programmable to be opened at predefined events to release water collected in said measurement chamber,
• a funnel or collector adapted to receive rain fall, said funnel or collector opening into said inlet port, and
• an ultrasonic transducer for transmitting and receiving acoustic signals into said measurement chamber, said ultrasonic transducer being programmable to determine the water level in said measurement chamber and being programmable to allow calibration of said rain gauge based on the distance between said ultrasonic transducer and said ball valve surface,
• a solar panel for power,
• a data logger with computer control for operational analysis, and
• one or more of a thermometer, anemometer, wind vane, hygrometer, barometer, ceilometer, present weather sensor and/or visibility sensor, snow depth sensor and pyranometer.

An automatic weather station including:

• a rain gauge for measurement of rain fall, said rain gauge including:
• a measurement chamber having an inlet port at one end and a drainage port at the other end, said drainage port being closed by a ball valve, said ball valve programmable to be opened at predefined events to release water collected in said measurement chamber,
• a funnel or collector adapted to receive rain fall, said funnel or collector opening into said inlet port, and
• an ultrasonic transducer for transmitting and receiving acoustic signals into said measurement chamber, said ultrasonic transducer being programmable to determine the water level in said measurement chamber and being programmable to allow calibration of said rain gauge based on the distance between said ultrasonic transducer and said ball valve surface,
• a housing with said rain gauge located at the top thereof to collect rainfall, said housing having a Stevenson screen below said rain gauge to shield meteorological instruments contained therein against precipitation and direct heat radiation from outside sources, while allowing air to circulate freely around them.