Interlock logic diagramming*
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Could someone please explain this operational relationship? Thank you, seeking help from @ZhiGE
This post was last edited by tjhuan on 2021-9-8 at 16:46. Can it be understood this way? 1. When the output of the trigger is 1, N is executed; these valves are not allowed to move ； When the trigger output is 0, Y is executed; these valves are allowed to close ； 2. What is the meaning of executing N? Is it a protection function?
This post was last edited by ZhiGE on 2021-9-9 08:12. 1. All SIS interlocks are fail-safe, meaning “1” indicates normal operation, while “0” indicates interlock activation. When the output side of the aforementioned logic RS flip-flop is “0”, the PRC shuts down. 2. Meanwhile, the PRC trip signal “0” is inverted after a 30-second delay to become 1, which represents the allow signal ； That is, 30 seconds after the PRC stops, it is allowed to close the suction and discharge MOVs of the PRC. (30-second delay is to prevent excessive suction force when the compressor is running at high speed, which could cause damage to the equipment or pipes.) When the compressor is operating normally, the MOVs must not be turned off. Also note that for “allow shutdown,” it is necessary to meet another condition of the AND gate as well.
Expert, expert, expert..... Thank you. . .
Motor Operated Valve generally refers to electric valves