A pressure transmitter is a device that converts pressure into a pneumatic signal or an electric signal for control and remote transmission. The physical pressure parameters of gas, liquid, etc., felt by the load cell sensor are converted into standard electrical signals to provide indicating alarms, recorders, regulators and other secondary instruments with measurement, indication and process adjustment.
There are two pressure transmitter types: electric and pneumatic. The electric pressure transmitter is powered by a DC power supply, providing a variety of output signal options, including 4～20mA DC, 0～5V DC, 1～5V DC, 0～10mA DC. Electric pressure transmitters have several kinds of output modes, including RS232 or RS485 digital output and Hart protocol, and they can be directly connected with PLC, DCS system or digital display instrument. The unified output signal of the pneumatic pressure transmitter is a gas pressure of 20-100KPa. The pneumatic pressure transmitter is generally suitable for some special occasions such as high temperature.
In today's production process, pressure transmitters are used more and more widely, and their stability and reliability have become a strong guarantee for the petrochemical industry. The petrochemical industry's demand for pressure transmitters is mainly concentrated in three aspects: reliability, stability and high precision:
(1) The pressure transmitter will drift as the environment and temperature changes during use, so measurement values can be inaccurate. At this time, it is necessary to ensure that the pressure transmitter has high reliability.
(2) The stability of pressure transmitters mainly depends on obtaining correct measurement values in different working environments, thereby maintaining the stability of production and ensuring the consistency of the process, which is the reason why the petrochemical industry emphasizes stability.
(3) On the basis of stability and reliability, high precision is an indispensable requirement for pressure transmitters in the petrochemical industry. The higher the precision of the product, the higher the accuracy of the measured value.