How Pressure Sensors Work

How Pressure Sensors Work

The pressure sensor is generally a combination of a process connection element, a measurement circuit, and a differential pressure sensor. It can effectively convert the pressure signal of the received liquid and gas into a standard current signal, and then provide it to the regulator. Loggers and indicator alarms are used to carry out related procedures, indications, and adjustments of measurements.

Now introduce their respective characteristics.

Ceramic pressure sensor

The sensor is corrosion-resistant. It does not pass through the liquid and the pressure is directly applied to the front surface of the sensor ceramic diaphragm. At this time, the ceramic diaphragm will form a very small deformation. The thick film resistor is printed on the back of the diaphragm so that it can be connected to a Wheatstone bridge. According to the piezoresistive effect of piezoresistors, the bridge can be formed with a highly linear voltage signal, which is proportional to the excitation voltage of the exchanging temperature transmitter, and is proportional to the pressure. The standard signal is calibrated on the basis of the difference in pressure range. It can be compatible with strain gauge sensors. According to the laser calibration, the time stability and temperature stability of the sensor are very high. Its self-contained temperature compensation range is 0 to 70°C. It can also be in direct contact with many media.

Sapphire pressure sensor

It works on the principle of strain-resistance, and its metrology characteristics are very good because of the use of silicon-sapphire as a semiconductor sensing element. Sapphire has good insulating properties and elasticity; and sapphire is high in hardness and stronger than silicon, so the user does not need to be afraid that it will deform; sapphire is composed of single crystal insulator elements, so it will not creep, fatigue and Lag phenomenon. Therefore, using silicon-sapphire as a semiconductor sensing element, the influence of temperature on its measurement becomes very small. Even in a very high temperature environment, its operating characteristics can be maintained very well. Moreover, Sapphire also has a strong anti-radiation effect. By using this sensitive element, the product yield can be greatly ensured, measurement repeatability can be improved, and the manufacturing process can be simplified. Using silicon-sapphire as a transmitter and pressure sensor for semiconductor sensors, it can work normally in many harsh environments. Its cost-effectiveness, small temperature error, high precision, and high reliability .

Strain gauge pressure sensor

There are many kinds of such sensors, capacitive, resonant, inductive, resistive strain gauges, piezoresistive, etc., but the most widely used is piezoresistive, it has better linearity, higher accuracy, and comparison. Low price.

Diffused silicon pressure sensor

When the pressure of the medium to be measured acts on the sensor diaphragm, the diaphragm will form a certain micro-displacement, which is proportional to the pressure of the medium. At this time, the resistance value of the sensor will change. The electronic circuit is used to detect this change, and then a standard measurement signal can be converted and output which corresponds to this pressure.