The liquid level transmitter has throw-in type level transmitter (rod type, cable type),flange type level transmitter (single flange, double flange) and magnetic flapper level transmitter and floating ball level transmitter , etc.
The characteristics of Huahai series throw-in type level transmitter are flexible installation, convenient use, simple calibration,field display,signal isolation and amplification,cutoff frequency interference design,strong anti-interference ability,anti-condensation,lightning protection,anti-corrosion,anti-clogging design,etc.The probe diameter can be selected from 19mm to 42mm,with wiring reverse and overvoltage protection,current limiting protection, and ultra-wide price range for easy selection.
Working principle: the throw-in type level transmitter is a static pressure level gauge that uses the pressure principle to measure the liquid level.Generally the length of the throw-in type cable is equal to the length from the lowest point of the measured liquid level to the highest liquid level plus the distance from the mounting plane to the highest point of the liquid level.Using static pressure measurement principle:
When the throw-in type level transmitter is put into a certain depth of the measured liquid,the pressure on the liquid-facing surface of the sensor is: P =ρ.g.H + Po
P：pressure on the liquid-facing surface of the liquid level gauge
ρ：the density of the measured liquid
g：local gravity acceleration
Po：atmospheric pressure on the liquid surface
H：the depth of the throw-in type level transmitter into the liquid.
At the same time, the pressure of the liquid is introduced into the positive pressure cavity of the sensor through the gas-conducting stainless steel, and then the atmospheric pressure Po on the liquid surface is connected with the negative pressure cavity of the sensor to offset the Po on the back of the sensor, so that the pressure measured by the sensor is:ρ.g.H,obviously, by measuring the pressure P, the liquid level depth can be obtained.
Application areas of the throw-in type level transmitter: low liquid level monitoring of open liquid tanks,depth or level measurement of wells or open waters,groundwater level measurement,level measurement and control in sewage treatment, water supply, chemical and pharmaceutical industries,constant pressure water supply systems and other industries.Over temperature compensation and linear correction. Converted to 4-20mADC standard current signal output.The sensor part of the throw-in type level transmitter can be directly put into the liquid,and the transmitter part can be fixed by flange or bracket,which is very convenient for installation and use.
Characteristics of throw-in type level transmitter
1. Long service life
The diaphragm of the liquid level transmitter adopts a high-tech laser modulation circuit, and the sensor housing is made of stainless steel.
2. Easy installation
It is only necessary to put the probe of the throw-in type level transmitter into the liquid,and lead the signal line to connect the secondary instrument for liquid level measurement.
3. Good temperature stability
The throw-in type level transmitter itself realizes temperature compensation in 0-70 °C, and a temperature compensation circuit is added in the signal conversion circuit to eliminate the influence of temperature drift of the circuit on the accuracy, ,thereby improving accuracy.