Reasons why pressure switches are prohibited in this project
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One of the recent projects specified in its requirements for pressure instruments that \"pressure switches shall not be used in this project, unless there are special requirements from the patent holder or the equipment supplier.\" I’m not sure why such a requirement was put in place
It was also mentioned in 50770, roughly stating that analog measuring instruments should be used. Pressure switches contain moving parts, so they are less safe compared to pressure transducers, right?
Analog signals change continuously, and it is possible to view historical trends, which is useful for identifying faults. The transmitter can define failure modes, which helps to reduce unintended shutdowns caused by failures in the field instruments.
The pressure switch has a set value; it does not show the actual pressure, and there is no visual indication provided by a transmitter
Previously, the pressure switch acted quickly, while there was a delay in the measurements taken by the transmitter. Sometimes chains require the use of pressure switches. But pressure switches are difficult to calibrate. Transmitters have improved now. Gradually, pressure switches were no longer used. Many pressure switches have also been converted into transmitters.
Previously, the pressure switch acted quickly, while there was a delay in the measurements taken by the transmitter. Sometimes chains require the use of pressure switches. But pressure switches are difficult to calibrate. Transmitters have improved now. Gradually, pressure switches were no longer used. Many pressure switches have also been converted into transmitters.
Code for Design of Safety Instrumentation in Petrochemical Industries - GB_T50770-2013 6.1.1 Analog measuring instruments are preferred for the measuring instruments in safety instrumentation systems