Classification and advantages of pressure transmitters
The current types of pressure transmitters are roughly divided into: resistance strain gauge pressure transmitter, semiconductor strain gauge pressure transmitter, piezoresistive pressure transmitter, inductive pressure transmitter, capacitive pressure transmitter, resonance Type pressure transmitter and capacitive acceleration sensor, etc.
The main function of the pressure transmitter is to transmit the pressure signal to the electronic device. The basic principle is: convert the mechanical signal of water pressure into a current (4-20mA). The pressure of such an electronic signal has a linear relationship with the voltage or current. , Is generally a proportional relationship, therefore, the output voltage or current of the transmitter increases with the increase of pressure. From this, a relationship between pressure and voltage or current is obtained. The two pressures of the measured medium of the pressure transmitter enter High pressure chamber and low pressure chamber. The pressure of the low pressure chamber adopts atmospheric pressure or vacuum, which acts on the isolation diaphragms on both sides of the delta element (ie the sensitive element), and is transmitted to both sides of the measuring diaphragm through the isolation sheet and the filling liquid in the element. The pressure transmitter is composed of a measuring diaphragm and the electrodes on both sides of the insulating sheet to form a capacitor. When the pressures on both sides are inconsistent, the measuring diaphragm will be displaced. The displacement is proportional to the pressure difference. Therefore, the capacitances on both sides are not equal. Through the oscillation and demodulation link, it is converted into a signal proportional to the pressure.