When the pressure directly acts on the surface of the measuring diaphragm, the diaphragm will be slightly deformed. The high-precision circuit on the measuring diaphragm converts this tiny deformation into a highly linear voltage signal proportional to the pressure and excitation voltage, and then the voltage signal is converted into an industrial standard 4-20ma current signal or 1-5V voltage signal by using a special chip.
Because the measuring diaphragm adopts standard integrated circuit and contains linear and temperature compensation circuits, it can achieve high accuracy and stability. The transmission circuit adopts special two-wire chip, which ensures the output of 4-20ma current signal of two-wire system and is convenient for field wiring.
Working principle of diffusion silicon pressure transmitter
The pressure of the measured medium directly acts on the diaphragm (stainless steel or ceramic) of the sensor, causing the diaphragm to generate micro-displacement in direct proportion to the pressure of the medium, so that the resistance value of the sensor changes, which is detected by the electronic circuit and converted into a standard measurement signal corresponding to the pressure.
Working principle of ceramic pressure transmitter
The pressure directly acts on the front surface of the ceramic diaphragm, causing slight deformation of the diaphragm. Thick film resistor is printed on the back of ceramic diaphragm and connected to form Wheatstone bridge (closed bridge). Due to the piezoresistive effect of the piezoelectric resistor, the bridge generates a highly linear voltage signal proportional to the pressure and excitation voltage.
Working principle of strain pressure transmitter
Resistance strain gauge is a kind of sensitive device that converts the strain change on the measured part into electrical signal. It is one of the main components of piezoresistive strain transmitter. Metal resistance strain gage and semiconductor strain gauges are widely used. There are two kinds of metal resistance strain gauges: metal wire strain gauges and metal foil strain gauges. Usually, the strain gauge is closely combined with the substrate that produces mechanical strain through a special adhesive. When the stress of the substrate changes, the resistance of the strain gauge changes, so the voltage applied to the resistor changes.
The above contents are provided by Huai 'an Sanchang Instrument.