Capacitive differential level sensor unaffected by dielectric constant change - comprises isolated surfaces with capacitance on immersion measured using constant ratio of capacitances

摘要

Capacitative level sensor consists of two isolated surfaces arranged so that the capacitance of one surface increases w.r.t. the other as the measured medium rises or falls. Capacitances of the surfaces are measured to determine the level. Each surface is a charging capacitance of a multi-vibrator in an electronic circuit. ADVANTAGE - Not affected by changes in dielectric constants.