According to the measuring range, pressure transmitter can be divided into three types: general pressure transmitter (0.001MPa~100MPa), differential pressure transmitter (0~ 1.5kPa), and negative pressure transmitter. It transmits pressure signal into electronic equipment and then the pressure is displayed by computer. Its working principle is to convert the mechanical signal like liquid pressure or gas pressure into electric signal like current or voltage.
The pressure has a linear direct proportional relation with the voltage or current, therefore, the voltage or current will increase with the increase of the pressure, and then a relationship expression between the pressure and voltage or current can be obtained to achieve the aim of measuring the gas and liquid pressure.