Pressure Transmitter is an instrument that converts pressure signals into standard electrical signal outputs. Its conversion process mainly relies on the following methods.
A common method is to use the principle of strain gauges. In the pressure-sensitive element of Pressure Transmitter, strain gauges are usually installed. When pressure acts on the pressure-sensitive element, the pressure-sensitive element will undergo a slight deformation. Strain gauges are a type of resistance material that is very sensitive to deformation, and its resistance value changes with the size of the deformation. By measuring the change in the resistance value of the strain gauge and then processing it with a specific circuit, it can be converted into an electrical signal output proportional to the pressure. For example, when the pressure increases, the deformation of the pressure-sensitive element increases, and the resistance value of the strain gauge also increases accordingly. After the circuit conversion, the output electrical signal strength will also increase.
Another method is to use the piezoresistive effect. When some materials are subjected to pressure, their resistivity changes. Pressure Transmitter uses this piezoresistive material to make pressure-sensitive elements. When pressure acts on the pressure-sensitive element, the resistivity of the piezoresistive material changes. By measuring this resistivity change and amplifying and processing it with the circuit, an electrical signal output corresponding to the pressure can be obtained. This method has high sensitivity and accuracy, and can accurately reflect small pressure changes.
Another method is to use the principle of capacitance. The capacitive sensor in the Pressure Transmitter consists of two parallel electrode plates with a layer of deformable insulating medium in between. When pressure acts on the insulating medium, the thickness of the medium will change, resulting in a change in the capacitance value. By measuring the change in capacitance value and converting it through the circuit, an electrical signal output related to the pressure can be obtained. The capacitive Pressure Transmitter has the advantages of fast response speed and good stability.
In actual Pressure Transmitters, multiple technologies and circuit designs are usually combined to improve the accuracy and reliability of conversion. For example, a temperature compensation circuit is used to eliminate the influence of temperature changes on pressure measurement; a signal amplification and filtering circuit is used to improve the strength and stability of the electrical signal. At the same time, in order to meet different application requirements, the Pressure Transmitter will also standardize the output electrical signal, such as outputting a 4-20mA current signal or a 0-5V voltage signal, so as to connect and communicate with various control systems and instruments.
In short, Pressure Transmitter converts pressure signals into electrical signals through strain gauges, piezoresistive effect, capacitance principle and other methods, providing an accurate and reliable means for pressure measurement and control.
