Several questions regarding the solenoid valve box
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I have a few questions regarding the solenoid valve box: 1. Can the “local/remote” mode of the solenoid valve box be switched only using a knob on the valve box itself, with no possibility of controlling it from the DCS/PLC? 2. If the solenoid valve box is in the “local” mode, can the DCS still be operated? In this case, can the DCS’s “override on” and “override off” functions be activated? 3. Many specification books state that \"a permanent schematic diagram of the equipment should be drawn on the solenoid valve box, and the operation switches for the solenoid valves should be arranged in the positions indicated on this schematic diagram.\" What exactly is meant by a \"schematic diagram\" here? It would be helpful to have actual photos for reference
I’ve never seen this format you’re talking about; does the solenoid valve still need an on-site/remote setting? According to what you say, it’s not possible to operate it when the DCS is in that location; if you try to operate it, it will definitely show “Operation timed out””
“\"Local/Remote\" refers to the solenoid valve box, not the solenoid valve; moreover, it is \"override\", not \"timeout\"”
1. It is possible to choose between remote and local operation on DCS/PLC, but the reliability and security are not as high as those of a local control panel. 2. As for the timeout issue, it depends on the requirements specified in the design drawings; both options can be implemented, depending on the design and the wiring setup. 3. I didn’t understand clearly
“What does “override” mean? I’ve been influenced by the master
1. Remote/local selection: it can be set on the DCS/PLC, on the solenoid valve box, or at both locations； 2. Override control is a form of selective control; in a selective control system, the solenoid valve serves as the switching device ； 3. If the remote/local selection is set to local, it can only be switched manually at the electromagnetic box.