What do HM and ZOI mean in DCS?
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What do HM and ZOI mean in DCS? For example, HM1101, ZOI1801. There’s also PIK1101; the experienced technician said it’s a manual operator.
Please, the original poster, provide more detailed background information
ZOI generally refers to the indication of valve position or opening degree, and is often used for the open-circuit feedback of logic solenoids. PIK generally refers to a pressure indication operator, which is often used in standalone control panels or for simulation in DCS systems. HM generally refers to historical memory trends, and it is commonly used in DCS configurations.
In DCS, at special valves such as the regeneration slide valve in catalytic cracking, there is an HM indicator; the technician said that operating it during a power outage can cause the slide valve to move one and a half strokes. Isn’t ZI used for indicating the valve position? So what does O mean? What is the difference between PIK and PIC operations?