【Q&A Question 077】March 18, 2017
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This post was last edited by 955559 on 2017-7-21 22:31. [Q&A Question No. 077] 2017.03.18: What is the function of the bypass button switch in the SIS system settings? The reference answers will be visible after responding; points are awarded by identifying the key points. (Unless otherwise specified, all questions and answers are based on hydrogenation units.) ) Setting various bypass button switches is intended to enable the opening of valves and the corresponding equipment, when repairing the instrument or when the process conditions do not meet the requirements for starting up the equipment. 2017 Q&A Summary Thread (updates have begun) http://bbs.hcbbs.com/thread-1657793-1-1.html 2017 Daily Question Summary Thread (updates have begun) http://bbs.hcbbs.com/thread-1657794-1-1.html 2016 Q&A Summary Thread (updates completed) http://bbs.hcbbs.com/thread-1597792-1-1.html Third Phase of Haichuan’s Outstanding Management Members Selection Contest http://bbs.hcbbs.com/thread-1655902-1-1.html (Source: Haichuan Chemicals Forum)
Provides protection in the event of a power outage
Settings for the online maintenance of field devices such as SIS transmitters and detection switches. Because in bypass mode, the functionality of SIF as well as its safety integrity are limited. Therefore, the design and operational management of bypass systems have become one of the key focus areas in SIS projects
The design philosophy of SIS is to avoid starting operations via bypasses; bypass switches are only used in abnormal situations
It ensures that in the event of an alarm or malfunction in the instrument, it can be repaired or replaced without shutting down the machine.
The interlock cutout is used only during maintenance and system testing
Setting up various bypass button switches is intended to enable the opening of valves and the corresponding equipment, when repairing instruments or when the process conditions do not meet the requirements for starting up the equipment.
Used during maintenance and system testing, it is particularly convenient for manual handling in special situations.