Question 1

piezoresistive pressure transmitter

Accepted Answer

One of the main components of piezoresistive pressure transmitters is the resistance strain gauge. It is a sensitive device that converts the strain change on the DUT into an electrical signal.

Usually, the strain gauges are closely bonded to the substrate that generates mechanical strain with a special adhesive. When the stress of the substrate changes, the resistance strain gauge also deforms together. Change the resistance value of the strain gauge, so that the voltage applied to the resistance changes. The transmitter has extremely low price and high accuracy and good linearity characteristics.

Question 2

Diffused silicon pressure transmitter

Accepted Answer

Diffused silicon pressure transmitters were introduced in the mid-1990s. It utilizes the piezoresistive effect of elastic elements. When the pressure of the measured medium directly acts on the diaphragm of the sensor, the diaphragm produces a micro-displacement proportional to the pressure of the medium, which changes the resistance value of the sensor. This change is detected electronically. And convert and output a unified standard signal.

Compared with traditional products, this transmitter has the advantages of advanced technology, reliable performance, convenient installation, high accuracy and small size.

Question 3

Ceramic pressure transmitter

Accepted Answer

Corrosion-resistant ceramic pressure transmitters have no liquid transfer. When the pressure acts on the ceramic diaphragm, the diaphragm will produce a slight deformation. Make the thick film resistor printed on the back of the ceramic diaphragm pass through the Wheatstone bridge (closed bridge) connected to it. Output a voltage signal proportional to the excitation voltage.

The pressure physical quantity is measured through the built-in circuit of the transmitter and converted into a unified standard signal.

The transmitter can introduce various media (corrosive and non-corrosive gases, liquids) directly to the ceramic diaphragm.

The thermal stability of the ceramic and its thick-film resistance allow it to operate over a temperature range as high as -40°C to 135°C.

Therefore, it has high measurement accuracy, good stability, strong output signal and low price.

Question 4

Piezoelectric pressure transmitter

Accepted Answer

Piezoelectric pressure transmitters work on the piezoelectric effect.

The crystal is anisotropic, and when a force is applied along a certain direction, the crystal can produce an electric effect. When the mechanical force is removed, it will return to the uncharged state again. The piezoelectric materials mainly used in sensors are quartz, sodium potassium tartrate and ammonium dihydrogen phosphate.

The transmitter is mainly used in the measurement of acceleration and pressure. It has the characteristics of simple structure, small size, light weight and long service life. But it can only be used to measure dynamic stress.

Question 5

Capacitive pressure transmitter

Accepted Answer

The capacitive pressure transmitter is composed of a measuring diaphragm and electrodes on both sides of the insulating sheet to form a capacitance.

When the pressure on both sides is inconsistent, the displacement of the measuring diaphragm is proportional to the pressure difference. Therefore, the capacitance on both sides is not equal.

Through the oscillation and demodulation link, it is converted into a signal proportional to the pressure. Then the pressure physical quantity is measured and converted into a unified standard signal through the transmission circuit.

It has high precision, corrosion resistance, pollution resistance and good stability. It is recognized as an ideal instrument for detecting low vacuum pressure at home and abroad. It is mainly used in various fields of civil industry, and plays a unique role in military industries such as aerospace industry and nuclear industry.

Extended Reading: Smart pressure transmitter

Capacitive pressure transducer

Category: Pressure Measurement Sloutions

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