KST – KROMSCHRÖDER SYSTEMTECHNOLOGY
188.8.131.52.2.2 High gas protection
High gas pressure protection to prevent excessive gas flow shall be fitted in all circumstances except when:
- the equipment supply pressure does not exceed 100 mbar; and
- the pressure drop across the gas pressure regulator is less than 30 % of the normal operating minimum outlet pressure; and
- regulator failure does not result in an unsafe start-gas rate being obtained; and
- the equipment capacity is below 600 kW.
Where high gas pressure protection is required, the system shall prevent start-up1) or cause safety shut-down or, in the case of no operator supervision, lock-out (see 3.52)2) in the event of a pre-determined pressure being exceeded.
This functions shall meet the requirement of the protective system according to 5.7.2 and 5.7.3.
Gas pressure detectors shall comply with EN 1854.
The following chapters are printed with the permission of the DIN Deutsches Institut für Normung e.V. (German Institute for Standardization). For the implementation of the DIN Standard, the version with the most recent issue date is deemed authoritative. This is available from Beuth Verlag GmbH, Burggrafenstrasse 6, 10787 Berlin, Germany.
Our note on this Standard:
1) The pressure switch should be arranged upstream of the main shut-off valves in order to prevent STARTING of the system.
2) We recommend a fault lock-out to preclude the possibility of uncontrolled re-cycling (restart).