Hysteresis of Fork Liquid Level Switches in Specific Applications

Product catalog summary

Introduction
Fork Liquid Level Switches utilize piezoelectric devices for vibration drive and detection. When the resonant vibrating forks contact the measured medium, the vibration frequency decreases, leading to a reduced output signal. An integrated circuit analyzes this signal to output a switch signal. The hysteresis effect is crucial for measurement accuracy.

Hysteresis Explanation
Hysteresis is a static index in sensors, describing the loop phenomenon where the state quantity is inconsistent during cyclic increases and decreases of a state variable. For Fork Liquid Level Switches, hysteresis is the distance between the switching points when the liquid level rises (X1) and falls (X2).

Optimization of Hysteresis
Jiwei optimizes hysteresis by using different algorithms based on media density and calibrating according to experimental results. In applications like measuring slurry in coal chemical industry desulfurization towers, the viscous and fluctuating nature of the slurry can cause false alarms.

Design Improvements
To enhance reliability, Jiwei engineers incorporate reasonable delay times in circuits to optimize hysteresis, reducing false alarms and ensuring accuracy. It is recommended to install the switches vertically, away from inlets, outlets, and mixing areas to avoid interference.

Catalog excerpts

Hysteresis of Fork Liquid Level Switches in Specific Applications-1

Hysteresis of Fork Liquid Level Switches in Specific Applications In Fork Liquid Level Switches, piezoelectric devices are utilized to achieve vibration drive and detection. Once resonant vibrating forks contact with measured medium, vibration frequency of forks substantially decreases, and the output signal from piezoelectric detection device decreases accordingly. Then an integrated circuit is designed to analyze the signal from piezoelectric device and output a switch signal as a result. The hysteretic effect of Fork Liquid Level Switch is highly related to measurement accuracy. Hysteresis is an important static index in sensors. Hysteresis refers to the phenomenon that when showing the relationship between the quantity of state and the variables of state in the substance obtained by test bed, it can be seen to draw a loop phenomenon which the quantity of state is not consistent at the time of increasing and decreasing after the variable of state was increased or decreased cyclically in a predetermined range. For Fork Liquid Level Switches, due to its functional characteristics, hysteresis refers to that when the fork liquid level switch is vertically installed, the position when the level rises to the Shenzhen Jiwei Automations Ltd.

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Hysteresis of Fork Liquid Level Switches in Specific Applications-2

switching-point the tines is marked as X1, and the position when the level falls to the switching-point of the tines is marked as X2. The distance between X1 and X2 is the hysteresis of the fork liquid level switch. As shown in the figure, the horizontal axis X is the load and the vertical axis Y is the sensitivity output. Jiwei fully considers the hysteresis of the Fork Liquid Level Switches, to hysteresis, different algorithms are used for calculation according to the density of different media, and finally the calibration is carried out according to the experimental results. For example, in...

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Hysteresis of Fork Liquid Level Switches in Specific Applications-3

install the instrument in a vertical position and away from the inlet or outlet. In the case with mixing equipments, the installation positions of Fork Liquid Level Switches should be as far away from the mixing area as possible. Shenzhen Jiwei Automations Ltd.

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