Electrical circuit of an meter for density measurement of a mixture which is transported through pipelines,

摘要

1475593 Electro-physical measurement - density AKADEMIA GORNICZO-HUTNICZA IM STANISLAWA STASZICA 8 July 1974 [9 July 1973] 30131/74 Heading G1N The density of material conveyed in a pipe line is detected by a capacitor sensor 1. The capacitor controls the frequency of an oscillator 2a which is compared with a reference frequency from oscillator 2c and the differencefrequency-signal is shaped at 2f .. 2k and integrated to provide a D.C. indicator signal. The signal is TEMPERATURE COMPENSATED in stage 3 controlled by a temperature sensor 4 in the pipe-line. COMPENSATION for CONDUCTIVITY of the mixture is provided by a stage 2b which maintains constant the amplitude of the output of oscillator 2a which would otherwise vary with conductivity.