How to determine instrument air valve parameters

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There is an existing instrument air system. The customer has specified that the pressure for instrument air should be 750 kPa under normal conditions and 600 kPa as a minimum; for utility air, it should be 850 kPa under normal conditions and 650 kPa as a minimum. The design pressure requirement is 1200 kPa. How should the pressures of the safety valves on the instrument air storage tank and the utility air storage tank be set? There are also two pressure switches: high, very high; low, very low. These 4 signals are used to control the start and stop of the two compressors. I have set the values to 950 kPa, 1050 kPa, 650 kPa, and 600 kPa respectively. For the safety valve of the instrument air storage tank, I have set it at 850 kPa, while the value for the utility air is set at 1100 kPa. The control valve at the outlet of the instrument air is set at 750 kPa. Is this setting reasonable, or should the value for the instrument air storage tank also be set at 1100 kPa? Should the pressure setting of the control valve be set a bit higher? Please give me your guidance! If drawings are needed, I’ll provide them right away!