The current types of pressure transmitters are roughly divided into: resistance strain gauge pressure transmitters, semiconductor strain gauge pressure transmitters, piezoresistive pressure transmitters, inductive pressure transmitters, capacitive pressure transmitters, resonant pressure transmitters and capacitive acceleration sensors.
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)? Such an electronic signal pressure has a linear relationship with the voltage or current size, generally a proportional relationship. Therefore, the voltage or current output by the transmitter increases with the pressure. The two pressures of the measured medium of the pressure transmitter are passed into the high and low pressure chambers. The pressure in the low pressure chamber adopts atmospheric pressure or vacuum and acts on the isolation diaphragms on both sides of the δ element (ie, the sensitive element). It is transmitted to both sides of the measuring diaphragm through the isolation plate and the filling liquid in the element. The pressure transmitter is a capacitor composed of a measuring diaphragm and electrodes on both sides of the insulating sheet. ?When the pressure on both sides is inconsistent, the measuring diaphragm will be displaced, and the displacement is proportional to the pressure difference, so the capacitance on both sides is not equal. Through the oscillation and demodulation links, it is converted into a signal proportional to the pressure.
The main advantages of pressure transmitter
(1). Reliable work and stable performance.
(2). Special V/I integrated circuit, few peripheral components, simple and easy maintenance, small size, light weight, extremely convenient for installation and debugging.
(3). Aluminum alloy die-cast shell, three-terminal isolation, electrostatic spray protective layer, strong and durable.
(4) .4-20mA?DC two-wire signal transmission, strong anti-interference ability and long transmission distance.
(5). LED, LCD, and pointer three indicator meters make on-site reading very convenient. Can be used to measure viscous, crystallized and corrosive media.
(6). High accuracy and high stability. In addition to the imported original sensor which has been corrected by laser, the comprehensive temperature drift and non-linearity of the whole machine within the operating temperature range are precisely compensated.