Pressure transmitter is the most commonly used in industrial practice a sensor, which is widely used in various industrial automation environment, involving water conservancy and hydropower, railway transportation, intelligent building, production control, aerospace, military, petrochemical, oil, electricity, ship , Machine tools, pipes and many other industries. Here is a brief introduction to some of the principles of commonly used pressure transmitter and its application, pressure transmitter is used to measure the liquid, gas or steam level, density and pressure, and then the pressure signal into 4 ~ 20mA DC signal output.
Pressure transmitter is mainly capacitive pressure transmitter and diffusion of silicon pressure transmitter, ceramic pressure transmitter, strain gauge pressure transmitter. Pressure transmitter according to the pressure range can be divided into general pressure transmitter (0.001MPa ~ 35MPa) and differential pressure transmitter (0 ~ 1.5kPa), three kinds of negative pressure transmitter.
The main role of the pressure transmitter to the pressure signal transmitted to electronic equipment, and then display the pressure in the computer its principle is roughly: the pressure of the hydraulic pressure of the mechanical signal into current (4-20mA) such as electronic signal pressure and voltage or Current size into a linear relationship is generally proportional relationship. Therefore, the transmitter output voltage or current increases with increasing pressure and thus a relationship between pressure and voltage or current pressure transmitter of the two kinds of media under pressure into the high and low pressure chamber , The low-pressure chamber pressure using atmospheric pressure or vacuum, role in the δ element (ie, sensitive components) on both sides of the diaphragm, through the separator and the components of the filling liquid is delivered to the measuring diaphragm on both sides.
Pressure transmitter is measured by the diaphragm and the insulation on both sides of the electrodes on the composition of a capacitor. When the pressure on both sides of the inconsistency, resulting in measuring diaphragm displacement, the displacement and the pressure is proportional to the difference, so the capacitance on both sides do not, through the oscillation and demodulation link.