Circuit for measuring the moisture content of liquid petroleum products by examination of the capacitance

摘要

Circuit for measuring the moisture content of liquid petroleum products, in particular, fuels, by examining the capacitor with a capacitor k serving as a comparison standard_o (2), the capacitance of the liquid petroleum product without water content and a measuring capacitor k_M (1), in which the medium to be measured is filled, characterized in that the circuit of two synchronously operating oscillators (3, 4) for generating a of the capacitance of the precision capacitor k_M (1) derived square-wave pulse t_M and a of the capacitance of the comparison with normal capacitor k_o (2) derived square-wave pulse t_o there is a differential circuit (5) for the formation of a difference pulse δt from the rectangular pulse t_M and the rectangular pulse t_o is arranged, this difference pulse δt in a gate circuit (7) of one pulse block of a pulse oscillator (6) a number of pulses within the difference pulse δt, which are counted by a pulse counter (8) a value for the moisture content of the liquid petroleum product form, and for a pulsed delivery of the pulse blocks of the pulse oscillator (6), for controlling the start of the pulse selection in the gate circuit (7) and to control the counter (8) a clock oscillator (9) which, by means of the oscillators (3, 4) is synchronized, for presetting a clock pulse t_T is arranged.