Capacitive liquid level meter and a liquid level measurement method which was used

摘要

PROBLEM TO BE SOLVED: To provide an electrostatic capacity liquid level gauge not affected by the relative dielectric constants of a liquid and a gas. ;SOLUTION: This electrostatic capacity liquid level gauge is provided with a sensor section arranged with multiple pairs of level sensors each constituted of a pair of opposite electrodes in the height direction in a tank storing a liquid, a sensor selection section 20 selecting the level sensors in sequence, an electrostatic capacity measurement section 40, and a control calculation section 5 having a program memory implementing the electrostatic capacity signal measurement and liquid level calculation on individual level sensors in it. The electrostatic capacity type sensors include an aerial sensor S_n+1 wholly exposed in the air to measure the aerial electrostatic capacity, a liquid level sensor S_n having the liquid level, and a submerged sensor S_n-1 wholly submerged in the liquid to measure the submerged electrostatic capacity. The electrostatic capacity of the liquid level sensor S. and the height of the liquid level are measured, based on the aerial electrostatic capacity of the aerial sensor S_n+1 and the submerged electrostatic capacity of the submerged sensor S_n-1.;COPYRIGHT: (C)1997,JPO