Hi Guys, I use the PLC for my house. Between my PLC and Node Red I use Modbus communication. I would like to use special switch with indicator. I want to use PLC digital output as feedback at the switch. I would use the same switch to control the PLC output. When the PLC output changes, that change…

I presume this is a node red dashboard switch you are talking about. If so then to solve the problem you need to pickup the current PLC output state in node-red and feed it into the front of the switch, so the switch will change if the output changes.

Thanks for the reply. I've tried this solution before. It used at one PLC output. When I copied it, the others didn't work properly.

Well that is the only way to do it, you cannot make the switch follow the PLC output unless you know what the output is. The solution is to try again and find out what the problem was the first time.

Try again with a smaller simpler flow and if it doesn't work, share the flow so people have something to investigate for you

So this my simple flow: [{"id":"e4e6562f.f1a698","type":"modbus-write","z":"350f034d.94afcc","name":"Mosok_vil_write","showStatusActivities":true,"showErrors":false,"unitid":"1","dataType":"Coil","adr":"15002","quantity":"1","server":"4d5e1b27.37ea5c","x":1020,"y":80,"wires":[,]},{"id":"ec77ff58.f3…

[image] Adas1978: [{"id":"e4e6562f.f1a698","type":"modbus-write","z":"350f034d.94afcc","name":"Mosok_vil_write","showStatusActivities":true,"showErrors":false,"unitid":"1","dataType":"Coil","adr":"15002","quantity":"1","server":"4d5e1b27.37ea5c","x":1020,"y":80,"wires":[,]},{"id":"ec77ff58.f3d2"…

Unfortunately the flow is not importable. Please see this post for how to share the flow. You can edit the previous post to insert the backticks. [image] How to share code or flow json FAQs To share code samples or flow json in this forum, you need to take care to format …

However before doing that put a debug node on the output of the first and second nodes and see what is coming from them.

[{"id":"e4e6562f.f1a698","type":"modbus-write","z":"350f034d.94afcc","name":"Mosok_vil_write","showStatusActivities":true,"showErrors":false,"unitid":"1","dataType":"Coil","adr":"15002","quantity":"1","server":"4d5e1b27.37ea5c","x":1020,"y":80,"wires":[[],[]]},{"id":"ec77ff58.f3d2","type":"ui_switch…

Note that you have specified that the switch sends the boolean values true and false. This means that you must make sure that the value you are passing it is also a boolean value true or false, otherwise the switch will not understand the value it is being sent. So as suggested put debug nodes on …

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Switch with indicator

Dashboard

Colin 9 August 2019 07:31 8

Unfortunately the flow is not importable. Please see this post for how to share the flow. You can edit the previous post to insert the backticks.

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Switch with indicator

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