Hello There, I'm new to node red and I have a little problem whith my flow. I recover data from a S7- 1200 in order to create csv files. I was able to create this flow but there is still somethong missing. In order to work correctly my supervisor asked me to make this flow trigger when a bool …

Hi and welcome to the forum. I am not sure why you are doing what you are doing the way you are doing it. context variables are usually reserved for use internally by the flows. Why can't you get what ever it is that is changing the context to be an input into the flow and get things happening th…

This post in this thread may help you [image] Lighting controller ideas General Here you go... [{"id":"3984433f.b0374c","type":"function","z":"553814a2.1248ec","name":"Make Observable","func":"\n/**\n* make properties of `object` Observable\n* @param {string} name key na…

Sorry I should have been more specific. I'm recovering data from a siemens automate. I created a flow that create a csv file by recovering the data from the device. According to my supervisor, the flow should trigger when one boolean value become true. I created a flow context value to use in a swit…

I'm note sure I understand what this flow does. Can you explain it to me ? Best Regards !

[image] HWeber: I'm note sure I understand what this flow does. Can you explain it to me ? It does what you asked... [piJZP4h6xK] ... triggers something when a flow context value is changed

That said... [image] HWeber: In order to work correctly my supervisor asked me to make this flow trigger when a bool value become true by the sounds of it, you simply need an RBE (filter) node followed by a switch node to test when the incoming BOOL changes to true PLC --> RBE --> SWITCH (t…

Please can you give us some more information: Is this a project in an industrial setting - the supervisor is your boss , or is it an educational exercise? Exactly what is this boolean value which should trigger a flow and how does it get into Node-red? [image] HWeber: I'm recovering data from…

I'm working in a industrial setting, it's an internal project of my company. Here is the code of my flow : [{"id":"a3b1b0c573439f83","type":"inject","z":"79fd906cf1fbcb03","name":"","props":[{"p":"payload"},{"p":"topic","vt":"str"}],"repeat":"0.28","crontab":"","once":false,"onceDelay":0.1,"topic"…

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How to trigger flow when context value change

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E1cid 23 May 2022 10:07 3

This post in this thread may help you

Topic		Replies	Views
How to keep flow running after one of the triggers is false? General	30	1799	23 May 2020
Detect when context's variable changes its value Feature Requests	21	15433	30 May 2022
Streaming changes to context (NR5?) Feature Requests	21	299	29 March 2026
Logic error - can i get some input please? General	15	911	12 September 2018
Pass Variable if condition is true General function-node	15	535	27 January 2023

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How to trigger flow when context value change

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