Integrating rainfall gauge with memory and periodic drain valve - stores and integrates value of output from level sensor prior to each emptying operation on small collector

摘要

The rain is collected through a funnel (11) into a U-tube (10) of small capacity equipped with, e.g. a capacitive or ultrasonic level sensor (12) referred to a null point (OP). A drain valve (15) at the bend is opened (14) at one-minute intervals while the signal detected immediately before each operation is measured (13) and stored (16). The instantaneous signal (I) controls the frequency of a counter (17) which delivers a time integral (M) denoting the accumulated quantity of rain. The base frequency of the counter is varied with the input voltage (intensity signal). ADVANTAGE - More accurate readings can be taken remotely over longer periods from instrument incorporating relatively small container.