Pressure: The force of fluid medium acting on unit area. Its statutory unit of measurement is pascal, symbolized by Pa.
Absolute pressure(PA): Pressure measured based on absolute vacuum(zero pressure).
Gauge pressure(PG): Pressure measured based on actual atmosphere pressure.
Sealed pressure(PS): Pressure measured based on standard atmosphere pressure(101,325Pa).
Negative pressure: When the value of gauge pressure < actual absolute pressure. It is also called as vacuum degree.
Differential pressure(PD): The difference of pressure between any two points.
Pressure sensor: The device senses pressure and converts pressure signal into electrical output signal according to a certain pattern. There is no amplifier circuit inside the sensor. The full scale output is generally milivolt unit. The sensor has low carrying capacity and cannot interface computer directly.
Pressure transmitter: A transmitter can convert pressure signal into standardized electrical output signal with continuous linear functional relationship. The unified standard output signals are usually direct current: ① 4~20mA or 1~5V; ② 0~10mA 0~10V. Some types can interface with computer directly.
Pressure transmitter = Pressure sensor + Dedicated amplifier circuit
In practice, people often do not make a strict distinction between names of the two devices. Someone may speak of a sensor which howerver actually refers to a transmitter with 4~20mA output.
Post time: Oct-20-2023