The input type liquid level transmitter, also known as static pressure type liquid level sensor, is the extension and development of pressure transmitter technology application. It is based on the principle that the measured liquid static pressure is linear with the height of the liquid. It uses the piezoresistive effect of diffusion silicon or ceramic sensing element, and the capacitive pressure sensor converts the static pressure into electrical signal. After temperature compensation and linear correction, it is converted into 4-20madc or 0-5V standard signal output. The sensor part (sensor head) of the input type liquid level transmitter can be directly put into the measured medium, and the transmitter part can be fixed by flange or bracket, so it is very convenient to install and use. The figure below shows a typical input type liquid level transmitter YWB230 The actual picture of.
The volume, liquid height and weight of water, oil and paste can be accurately measured by input type liquid level transmitter. Generally, the input type liquid level transmitter has the following characteristics:
1. Good stability and high precision;
2. It can be directly put into the measured medium, which is quite convenient to install and use;
3. Solid structure, no moving parts, high reliability, long service life, from water, oil to paste with high viscosity can be measured with high precision;
4. Wide range temperature compensation is not affected by bubbling, deposition and electrical characteristics of the measured medium;
5. It has power reverse polarity protection and overload current limiting protection.
So, how to choose the appropriate input type liquid level transmitter correctly, what should be paid attention to when selecting the input type liquid level transmitter? The following factors should be considered in the selection of model:
First, first of all, it is necessary to make clear what the measured medium is, whether it has corrosivity, whether it contains high-speed moving solid particles, and how thick it is. According to these properties, select the appropriate product. For example, YWB040 It is a corrosion-resistant liquid level transmitter, suitable for liquid level measurement of corrosive liquid, Ywb160 capacitive input liquid level transmitter It can measure the liquid level with solid particles in the measuring medium;
Second, you should know your own signal output requirements. Generally, the output signal of the liquid level transmitter must match with the input signal of these devices. The common output signals are 4-20mA, 0-20mA, 0-10V, 1-5V and other analog signals;
Third, to know what power supply you can provide, the liquid level transmitter generally needs power supply. The commonly used working power supply is 24 VDC, 220 VAC, and the rarely used power supply is 12 VDC, 15 VDC, 48 VDC, 110 VAC, etc;
Fourth, the installation method: the liquid level transmitter is generally installed by thread or flange, and the wiring is terminal connection, which is installed on the instrument;
Fifthly, we should know the accuracy requirements: analyze the specific situation and then see whether the accuracy is applicable;
Sixth, the situation requirements, such as their specific application fields and scope, such as power plants, chemical plants, etc;
Seventh, size requirements, liquid level transmitter design is becoming smaller, the purpose of miniaturization is less space. Of course, users should be allowed to install intensively, and there is a cooling problem in dense installation, so the internal power consumption must be reduced. Therefore, attention should be paid to the value of internal power consumption.
In addition, there is a very special measurement situation is differential pressure type liquid level transmitter, it is installed at the bottom of the liquid container, through the gauge pressure signal to reflect the liquid level height. In the process of liquid level measurement and control in pharmaceutical, food and chemical industries, the container containing liquid often works under pressure. At this time, the conventional static pressure input type liquid level transmitter can not meet the measurement requirements of this situation. This article originates from Zetian sensing All rights reserved. Please keep the source.