FIELD: chemical, metallurgical, petroleum refining industries, water treatment. SUBSTANCE: invention is related to equipment for automatic test of level and presence of liquid in technological pipe-lines. Device includes two emitting and one receiving electroacoustic converters which are located on outer surface of wall of pipe-line. Second emitting converter is placed diametrically opposite to first emitting converter. First and second emitting converters are equidistant from receiving converter. Pulse generator is connected with output to emitting converters. Receiving converter, amplifier, first single-shot blocking oscillator, first adder, integrator, D C amplifier and second adder are connected in series. Input of second single-shot blocking oscillator is connected to output of pulse generator and its output is linked to input of first adder. Input of peak detector is connected to output of amplifier and its output is linked to first input of second adder. Pulse generator, third single-shot blocking oscillator, selector and amplifier are connected in series. Output of second adder is connected to first input of comparator and source of reference voltage is connected to second input of comparator. Output of comparator is connected to input of indicator. EFFECT: raised reliability and accuracy of test of level or presence of liquid in pipe-lines with various thicknesses of walls and various diameters. 2 dwg
