A pressure calibration system needs to accurately measure pressure and may also need to measure pressure transmitters.
A complete pressure calibration system includes components to generate, control and measure pressure (and normally to log data from some or all of these functions). Some systems include two or all of these functions in a single unit. A procedure to adjust the unit is also usually required. Pressure monitors and references are digital readouts or gages that convert the pressure into numerical pressure units. Pressure sources generate either pneumatic (gas) or hydraulic (oil, water or alcohol typically) pressure.
For PCT field applications, a hand-pump or comparison test pump can be used, in conjunction with a reference calibrator; these normally provide sufficient control for field applications. On the bench, for higher pressures and where a greater degree of control or automation is required, a gas bottle or shop air can be used with a controller. Deadweight testers and the related electronic deadweight tester are portable systems that provide all three functions: generation, control and measurement— in a single unit and are suitable for both field and bench use.
Analogue and digital pressure gauges are often used to monitor pressures in processes. Gages have an internal mechanical or electro-mechanical mechanism to convert input pressure to a reading. Sensors and transmitters comprise both a sensor assembly, to detect and measure the pressure, and a transmitter, which converts the pressure into an electrical signal, typically a 4-20 milliamp signal, that can be transmitted to a control panel, PLC or other readout.
Pressure Calibration
Pressure Calibration
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