Self-calibration externally bonded ultrasonic liquid level switch measurement system and measurement method thereof

Abstract

The invention discloses a self-calibration externally bonded ultrasonic liquid level switch measurement system which comprises an externally bonded ultrasonic liquid level switch host, a calibration probe, a high level measurement probe and a low level measurement probe, wherein the calibration probe is mounted in an empty liquid position inaccessible for a liquid level of a tank body or outside a liquid position without emptying of the liquid level; the high level measurement probe is mounted at a high level alarm point at the upper part of the outside of the tank body; the low level measurement probe is mounted at a low level alarm point at the lower part of the outside of the tank body; the high level measurement probe and the low level measurement probe are connected with the externally bonded ultrasonic liquid level switch host. The measurement system judges whether liquid exists by change of ratios of a signal of the calibration probe to signals of the high level measurement probe and the low level measurement probe; influences of material, thickness, temperature and coupling layer loss on the signals can be effectively removed; more stable and reliable measurement is realized; frequent calibration of a set value is not required; the mounting and debugging workload is low; the efficiency is high; frequent debugging is not required.

Description

technical field [0001] The invention relates to the field of tank liquid level measurement and alarm, in particular to a self-calibrating externally attached ultrasonic liquid level switch measurement system. Background technique [0002] At present, liquid level switches installed outside the container include externally attached liquid level switches, externally measured liquid level switches, and the like. Its working principle is to install a measuring head at the monitoring point where the liquid level needs to be detected outside the side wall of the container. The measuring head emits ultrasonic waves into the container wall. After the ultrasonic waves enter the container wall, they will be reflected back and forth between the inner and outer surfaces of the container wall. Multiple times to form an aftershock signal. The sound pressure transmission coefficient of ultrasonic waves entering the liquid from the inner wall of the container: [0003] [0004] [0...

AI Technical Summary

Problems solved by technology

[0008] The purpose of the present invention is to provide a self-calibrating externally attached ultrasonic liquid level switch measurement system that judges whether there is liquid by calibrating the ratio change of the probe signal amplitude and the high and low position measuring probe signal amplitude, which solves the problem of external installation measurement at present. The liquid level switch has a high misoperation rate, poor working stability and reliability, and requires manual calibration and adjustment during field use, which results in a large amount of installation and commissioning work and low efficiency.

Images