In modern industrial measurements, there is a float water level transmitter that detects buoyancy changes by buoyancy. It determines the change in the height of the liquid level based on the size of the buoyancy. Therefore, it is widely used in the measurement of water tank and groundwater level. But as a new type of industrial measuring instrument, we need to understand the construction and measurement principle of the float level sensor so that we can make a timely choice.

The construction of float water level transmitter

The float water level transmitter consists of three parts: detection, conversion and transmission. The detecting part is composed of a pontoon and a connecting rod, and the converting part is composed of a lever and a torsion tank, and the sensor is composed of a 316L stainless steel casing and a TE chip. When the liquid level is higher, the buoyancy of the pontoon is greater, and the torque received by the torque tube is smaller. The change of the torsion angle is transmitted to the sensor connected to the torque tube, which is the voltage of the float level trasmitter. The change is thus converted to a current output of 4-20 mA.

The measuring principle of float water level transmitter

Float water level transmitter is usually used for liquid level measurement. When the liquid level of the measured liquid rises, the liquid enters the measuring cylinder, and the volume of the discharged liquid increases with the increase of the liquid level of the float rod. According to Archimedes' law, the buoyancy of an object is equal to the volumetric weight of the liquid discharged by the object. Since the float rod is a small-weight, heavy-duty metal tube, the weight of the liquid discharged from the float is much smaller than the weight of the float itself, so the connecting piece on the upper part of the float is still in a tight state, and the torsion rod is subjected to the gravity of the float minus the discharge of the float. The weight of the liquid (the buoyancy of the pontoon) produces a varying twist, at which point the float level sensor outputs a varying current greater than 4 mA. When the liquid level of the measured liquid reaches the highest level, the pontoon is completely immersed in the liquid to be tested. At this time, the volumetric weight of the liquid discharged from the pontoon is a fixed value. At this time, the torsion force of the torsion bar is the weight of the pontoon itself minus The weight of the liquid discharged from the pontoon. At this time, the torsion bar is subjected to a fixed torsion force, and the current output from the pontoon level instrument is 20 mA, which is the height of the pontoon level sensor.

By knowing the construction and measurement principle of the float water level transmitter, you can choose your own sensor.