1 Scope
This standard specifies the pressure range and quality requirements of air supply for industrial process measurement and control instruments.
This standard is applicable to air supply for industrial process measurement and control instruments
2 Terms and definitions
For the purposes of this document, the following terms and definitions apply.
2.1
on line pressure
the pressure of the gas delivered by pipeline network from outlets of purifying devices to input ends of industrial process measurement and control instruments
2.2
ambient temperature limit
the lowest temperature in the place where the whole system is located, including outlets of purifying devices, pipeline network and industrial process measurement and control instruments
3 Pressure range
3.1 Pressure range of air supply at outlets of purifying devices
The gas supply pressure range at the outlet of the purifying device are 300 kPa～500 kPa and 500 kPa～800 kPa.
3.2 Pressure range of air supply at input ends of industrial process measurement and control instruments
3.2.1 Nominal values of the gas supply pressure range at the input end of industrial process measurement and control instruments are 140 kPa, 260 kPa, 350 kPa, 550 kPa and 700 kPa.
3.2.2 The allowable fluctuation range of gas supply pressure at the input end of the instruments is ±10% of its nominal values.
Foreword i
1 Scope
2 Terms and definitions
3 Pressure range
4 Quality
Annex A (Informative) Gas supply quality test
Annex B (Informative) Relevant formulas and figure
