Interlock issues in the SIS system
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Does the SIS system require interlock shutdown of the pumps? If the feed pumps are involved in such interlocks, then do those pumps also need to meet the SIL2 standard, just like the pneumatic valves?
This post was last edited by budaoweng123 on 2017-10-26 at 16:09 :lol Yes, SIS is applicable to E/E/PES; the first ‘E’ stands for ELECTRICAL. However, if you require that the components in the electrical control circuits also be SIL2 certified, the cost will be extremely high – probably only a few companies in China can afford it. In China, SIS is merely a formality, used to satisfy the safety inspection requirements.
Regarding safety instrument system issues, since the issuance of Document No. 116 by the State Administration of Work Safety, HAZOP analysis and SIL classification have been carried out for most new projects; however, more fundamental problems remain unresolved. We need to take things step by step.
Yes, it’s necessary to control the pump shutdown; if the device stops but the pump keeps running, that will cause damage
It is recommended to read more about the principles for empirical use in the IEC61511 standard.