How to trigger flow when context value change

HWeber · 23 May 2022 09:25

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 value become true. Can somebody help me.

Best Regards !

Trying_to_learn · 23 May 2022 09:56

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 that way?

(I don't know what a S7 - 1200 is)

E1cid · 23 May 2022 10:07

This post in this thread may help you

HWeber · 23 May 2022 10:11

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 switch node. My question is How to trigger the flow when this value change.

HWeber · 23 May 2022 10:16

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

Best Regards !

Steve-Mcl · 23 May 2022 10:23

It does what you asked...

piJZP4h6xK

... triggers something when a flow context value is changed

Steve-Mcl · 23 May 2022 10:25

That said...

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 (test is true) --> do stuff

jbudd · 23 May 2022 10:28

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?

Sounds like you have made some progress. Please show us what your Node-red flow so far looks like.

HWeber · 23 May 2022 11:14

Thank you

HWeber · 23 May 2022 11:32

I'm working in a industrial setting, it's an internal project of my company.

Here is the code of my flow :

Steve-Mcl · 23 May 2022 11:36

In order to make code readable and usable it is necessary to surround your code with three backticks (also known as a left quote or backquote ```)

``` 
   code goes here 
```

You can edit and correct your post by clicking the pencil icon.

See this post for more details - How to share code or flow json

jbudd · 23 May 2022 11:38

And make sure there is nothing commercially sensitive in the exported flow!

HWeber · 24 May 2022 07:32

Here is the correct json :

[{"id":"79fd906cf1fbcb03","type":"tab","label":"Selmoni Pulve Flow","disabled":false,"info":"","env":[]},{"id":"a3b1b0c573439f83","type":"inject","z":"79fd906cf1fbcb03","name":"","props":[{"p":"payload"},{"p":"topic","vt":"str"}],"repeat":"0.28","crontab":"","once":false,"onceDelay":0.1,"topic":"","payload":"","payloadType":"date","x":550,"y":40,"wires":[["9c49ccad81b32059"]]},{"id":"9c49ccad81b32059","type":"switch","z":"79fd906cf1fbcb03","name":"blockFlow is false?","property":"blockFlow","propertyType":"flow","rules":[{"t":"false"}],"checkall":"true","repair":false,"outputs":1,"x":730,"y":40,"wires":[["d6fed3aebccbda9d"]]},{"id":"d6fed3aebccbda9d","type":"debug","z":"79fd906cf1fbcb03","name":"","active":true,"tosidebar":false,"console":false,"tostatus":true,"complete":"payload","targetType":"msg","statusVal":"payload","statusType":"auto","x":750,"y":100,"wires":[]},{"id":"7d7743a0e1ede1bb","type":"inject","z":"79fd906cf1fbcb03","name":"block","props":[{"p":"payload"},{"p":"topic","vt":"str"}],"repeat":"","crontab":"","once":false,"onceDelay":0.1,"topic":"","payload":"true","payloadType":"bool","x":110,"y":80,"wires":[["2b7196943fe9e08e"]]},{"id":"1199dc42d750ac34","type":"inject","z":"79fd906cf1fbcb03","name":"unblock","props":[{"p":"payload"},{"p":"topic","vt":"str"}],"repeat":"","crontab":"","once":false,"onceDelay":0.1,"topic":"","payload":"false","payloadType":"bool","x":110,"y":40,"wires":[["2b7196943fe9e08e"]]},{"id":"2b7196943fe9e08e","type":"change","z":"79fd906cf1fbcb03","name":"","rules":[{"t":"set","p":"blockFlow","pt":"flow","to":"payload","tot":"msg"}],"action":"","property":"","from":"","to":"","reg":false,"x":310,"y":60,"wires":[[]]},{"id":"541f352241334120","type":"s7 in","z":"79fd906cf1fbcb03","endpoint":"fd48bf27a62cee6a","mode":"all","variable":"","diff":false,"name":"","x":100,"y":420,"wires":[["c8a35d05e145b0e5"]]},{"id":"c8a35d05e145b0e5","type":"switch","z":"79fd906cf1fbcb03","name":"Mesure_Write is fasle or true ?","property":"Mesure_Write","propertyType":"flow","rules":[{"t":"true"},{"t":"false"}],"checkall":"true","repair":false,"outputs":2,"x":370,"y":420,"wires":[["275f82d9f9e4c0de","a6d853488e6e7ca9"],["15f82642384cab00"]]},{"id":"fece6999e1cba138","type":"debug","z":"79fd906cf1fbcb03","name":"","active":true,"tosidebar":true,"console":false,"tostatus":false,"complete":"false","statusVal":"","statusType":"auto","x":1050,"y":320,"wires":[]},{"id":"1e850f2e403c2fb8","type":"s7 in","z":"79fd906cf1fbcb03","endpoint":"fd48bf27a62cee6a","mode":"single","variable":"FM_Write","diff":true,"name":"","x":240,"y":780,"wires":[["f12b4beddde95e1b"]]},{"id":"f12b4beddde95e1b","type":"debug","z":"79fd906cf1fbcb03","name":"","active":true,"tosidebar":true,"console":false,"tostatus":false,"complete":"false","statusVal":"","statusType":"auto","x":490,"y":780,"wires":[]},{"id":"d4ac1ee9d34cc8f0","type":"inject","z":"79fd906cf1fbcb03","name":"","props":[{"p":"payload"},{"p":"topic","vt":"str"}],"repeat":"","crontab":"","once":false,"onceDelay":0.1,"topic":"","payload":"false","payloadType":"bool","x":260,"y":860,"wires":[["c94976b5c21d64cf"]]},{"id":"c94976b5c21d64cf","type":"s7 out","z":"79fd906cf1fbcb03","endpoint":"fd48bf27a62cee6a","variable":"FM_Write","name":"","x":480,"y":860,"wires":[]},{"id":"72c838f4f69d3aef","type":"inject","z":"79fd906cf1fbcb03","name":"","props":[{"p":"payload"},{"p":"topic","vt":"str"}],"repeat":"","crontab":"","once":false,"onceDelay":0.1,"topic":"","payload":"true","payloadType":"bool","x":260,"y":920,"wires":[["c94976b5c21d64cf"]]},{"id":"8f62459ab7b90763","type":"debug","z":"79fd906cf1fbcb03","name":"","active":true,"tosidebar":true,"console":false,"tostatus":false,"complete":"payload","targetType":"msg","statusVal":"","statusType":"auto","x":810,"y":460,"wires":[]},{"id":"15f82642384cab00","type":"function","z":"79fd906cf1fbcb03","name":"","func":"msg.payload = null;\nreturn msg;","outputs":1,"noerr":0,"initialize":"","finalize":"","libs":[],"x":620,"y":460,"wires":[["8f62459ab7b90763"]]},{"id":"275f82d9f9e4c0de","type":"function","z":"79fd906cf1fbcb03","name":"","func":"var run = flow.get(\"run\");\nif (!run) \n    return null;\n\nvar reset = flow.get(\"msgReset\");\nif ( reset ) {\n    msg.reset = true;\n    flow.set(\"msgReset\", 0);\n}\n\nmsg.columns = 'Date,Debit,Pression,Vitesse,Volume,Temps_ms,Debit_moy_hmi,Pression_moy_hmi,Vitesse_moy_hmi,Volume_moy_hmi';\n\nmsg.payload.Date = msg.payload.Date.toLocaleString(\"fr-FR\");\nmsg.payload.Debit=Math.round(msg.payload.Debit*10000)/10000;\nmsg.payload.Debit = msg.payload.Debit.toLocaleString(\"fr-FR\");\nmsg.payload.Pression=Math.round(msg.payload.Pression*10000)/10000;\nmsg.payload.Pression = msg.payload.Pression.toLocaleString(\"fr-FR\");\nmsg.payload.Vitesse=Math.round(msg.payload.Vitesse*10000)/10000;\nmsg.payload.Vitesse = msg.payload.Vitesse.toLocaleString(\"fr-FR\");\nmsg.payload.Volume=Math.round(msg.payload.Volume*10000)/10000;\nmsg.payload.Volume = msg.payload.Volume.toLocaleString(\"fr-FR\");\nmsg.payload.Temps_ms = msg.payload.Temps_ms.toLocaleString(\"fr-FR\");\nmsg.payload.Debit_moy_hmi=Math.round(msg.payload.Debit_moy_hmi*10000)/10000;\nmsg.payload.Debit_moy_hmi = msg.payload.Debit_moy_hmi.toLocaleString(\"fr-FR\");\nmsg.payload.Pression_moy_hmi=Math.round(msg.payload.Pression_moy_hmi*10000)/10000;\nmsg.payload.Pression_moy_hmi = msg.payload.Pression_moy_hmi.toLocaleString(\"fr-FR\");\nmsg.payload.Vitesse_moy_hmi=Math.round(msg.payload.Vitesse_moy_hmi*10000)/10000;\nmsg.payload.Vitesse_moy_hmi = msg.payload.Vitesse_moy_hmi.toLocaleString(\"fr-FR\");\nmsg.payload.Volume_moy_hmi=Math.round(msg.payload.Volume_moy_hmi*10000)/10000;\nmsg.payload.Volume_moy_hmi = msg.payload.Volume_moy_hmi.toLocaleString(\"fr-FR\");\n\nreturn msg;\n","outputs":1,"noerr":0,"initialize":"","finalize":"","libs":[],"x":680,"y":380,"wires":[["39f5daad7f6a213f"]]},{"id":"39f5daad7f6a213f","type":"csv","z":"79fd906cf1fbcb03","name":"Test","sep":";","hdrin":"","hdrout":"once","multi":"mult","ret":"\\r\\n","temp":"","skip":"0","strings":false,"include_empty_strings":"","include_null_values":"","x":830,"y":380,"wires":[["fece6999e1cba138","ec9842fea9bcb15e"]]},{"id":"134379e35816f308","type":"inject","z":"79fd906cf1fbcb03","name":"","props":[{"p":"payload"},{"p":"topic","vt":"str"}],"repeat":"","crontab":"","once":false,"onceDelay":0.1,"topic":"","payload":"","payloadType":"date","x":240,"y":640,"wires":[["b5143e0408217981"]]},{"id":"723c72304afd162e","type":"function","z":"79fd906cf1fbcb03","name":"","func":"var run = flow.get(\"run\");\nif ( !run ) {\n  run = new Date().toISOString('fr-FR');\n  while ( run.includes('-') )\n    run = run.replace('-', '');\n  while ( run.includes(':') )\n    run = run.replace(':', '');\n  run = run.replace('T', '_');\n  run = \"/home/selmoni/public/Mesures_Pulve/Mesures_VVB001_\" + run.substring(0,15) + '.csv';\n} else {\n  run = false;\n }\nflow.set(\"run\",run); \nflow.set(\"msgReset\", true);\nmsg.payload = run;\n\nreturn msg;","outputs":1,"noerr":0,"initialize":"","finalize":"","libs":[],"x":660,"y":600,"wires":[["d0d53f6f96679704"]]},{"id":"a036d1dcaa78546e","type":"debug","z":"79fd906cf1fbcb03","name":"","active":true,"tosidebar":true,"console":false,"tostatus":false,"complete":"payload","targetType":"msg","statusVal":"","statusType":"auto","x":1150,"y":600,"wires":[]},{"id":"ec9842fea9bcb15e","type":"function","z":"79fd906cf1fbcb03","name":"","func":"msg.filename = flow.get(\"run\");\n\nreturn msg;","outputs":1,"noerr":0,"initialize":"","finalize":"","libs":[],"x":1020,"y":380,"wires":[["24aafcc3a783ed1d"]]},{"id":"24aafcc3a783ed1d","type":"file","z":"79fd906cf1fbcb03","name":"Mesures_VVB001_","filename":"","appendNewline":false,"createDir":true,"overwriteFile":"false","encoding":"none","x":1230,"y":380,"wires":[[]]},{"id":"f8f4f8103ff174fd","type":"switch","z":"79fd906cf1fbcb03","name":"Mesure_Start is fasle or true ?","property":"Mesure_Start","propertyType":"flow","rules":[{"t":"true"},{"t":"false"}],"checkall":"true","repair":false,"outputs":2,"x":150,"y":520,"wires":[[],["addbcc2c55f22396"]]},{"id":"addbcc2c55f22396","type":"function","z":"79fd906cf1fbcb03","name":"","func":"msg.payload = \"Mesures non lancés\";\nreturn msg;","outputs":1,"noerr":0,"initialize":"","finalize":"","libs":[],"x":380,"y":540,"wires":[["87af11f29f9e0034"]]},{"id":"87af11f29f9e0034","type":"debug","z":"79fd906cf1fbcb03","name":"","active":true,"tosidebar":true,"console":false,"tostatus":false,"complete":"payload","targetType":"msg","statusVal":"","statusType":"auto","x":590,"y":540,"wires":[]},{"id":"b5143e0408217981","type":"switch","z":"79fd906cf1fbcb03","name":"","property":"Mesure_Write","propertyType":"flow","rules":[{"t":"true"}],"checkall":"true","repair":false,"outputs":1,"x":450,"y":640,"wires":[["723c72304afd162e"]]},{"id":"d0d53f6f96679704","type":"trigger","z":"79fd906cf1fbcb03","name":"","op1":"","op2":"","op1type":"pay","op2type":"nul","duration":"-280","extend":false,"overrideDelay":false,"units":"ms","reset":"run","bytopic":"all","topic":"topic","outputs":1,"x":900,"y":600,"wires":[["a036d1dcaa78546e"]]},{"id":"30e7b58219494fec","type":"influxdb out","z":"79fd906cf1fbcb03","influxdb":"bc4ab5cb2a050021","name":"","measurement":"test","precision":"","retentionPolicy":"","database":"test","precisionV18FluxV20":"s","retentionPolicyV18Flux":"","org":"organisation","bucket":"bucket","x":910,"y":260,"wires":[]},{"id":"a6d853488e6e7ca9","type":"function","z":"79fd906cf1fbcb03","name":"","func":"var run = flow.get(\"run\");\nvar reset = flow.get(\"msgReset\");\n\nif (!run) {\n    return null;\n}\n    \nif ( reset ) {\n   msg.reset = true;\n   flow.set(\"msgReset\", 0);\n}\n\nmsg.payload.FM_Write = msg.payload.FM_Write.toString(\"fr-FR\");\nmsg.payload.Date = msg.payload.Date.toLocaleString(\"fr-FR\");\nmsg.payload.Temps_ms = msg.payload.Temps_ms.toLocaleString(\"fr-FR\");\n\nreturn msg;","outputs":1,"noerr":0,"initialize":"","finalize":"","libs":[],"x":680,"y":320,"wires":[["30e7b58219494fec"]]},{"id":"eefc44384a77e1f4","type":"s7 in","z":"79fd906cf1fbcb03","endpoint":"fd48bf27a62cee6a","mode":"single","variable":"FM_Write","diff":false,"name":"","x":240,"y":980,"wires":[["f4203ce747524ab9"]]},{"id":"f4203ce747524ab9","type":"change","z":"79fd906cf1fbcb03","name":"","rules":[{"t":"set","p":"Mesure_Write","pt":"flow","to":"payload","tot":"msg"}],"action":"","property":"","from":"","to":"","reg":false,"x":480,"y":980,"wires":[[]]},{"id":"701517c3828f566e","type":"s7 in","z":"79fd906cf1fbcb03","endpoint":"fd48bf27a62cee6a","mode":"single","variable":"Start_Mesure","diff":false,"name":"","x":250,"y":1040,"wires":[["a29550a7ef6da8df"]]},{"id":"a29550a7ef6da8df","type":"change","z":"79fd906cf1fbcb03","name":"","rules":[{"t":"set","p":"Mesure_Start","pt":"flow","to":"payload","tot":"msg"}],"action":"","property":"","from":"","to":"","reg":false,"x":480,"y":1040,"wires":[[]]},{"id":"fd48bf27a62cee6a","type":"s7 endpoint","transport":"iso-on-tcp","address":"192.168.200.3","port":"102","rack":"0","slot":"1","localtsaphi":"01","localtsaplo":"00","remotetsaphi":"01","remotetsaplo":"00","connmode":"rack-slot","adapter":"","busaddr":"2","cycletime":"500","timeout":"1500","name":"Selmoni_Pulve","vartable":[{"addr":"DB10,DTL272","name":"Date"},{"addr":"DB26,DWORD410","name":"Temps_ms"},{"addr":"DB26,REAL418","name":"Debit"},{"addr":"DB26,REAL414","name":"Pression"},{"addr":"DB26,REAL426","name":"Vitesse"},{"addr":"DB26,REAL422","name":"Volume"},{"addr":"DB26,X0.0","name":"Start_Mesure"},{"addr":"DB26,X0.5","name":"FM_Write"},{"addr":"DB26,REAL38","name":"Debit_moy_hmi"},{"addr":"DB26,REAL42","name":"Pression_moy_hmi"},{"addr":"DB26,REAL46","name":"Vitesse_moy_hmi"},{"addr":"DB26,REAL14","name":"Volume_moy_hmi"}]},{"id":"bc4ab5cb2a050021","type":"influxdb","hostname":"127.0.0.1","port":"8086","protocol":"http","database":"test","name":"test","usetls":true,"tls":"d50d0c9f.31e858","influxdbVersion":"1.8-flux","url":" http://localhost:8086","rejectUnauthorized":false},{"id":"d50d0c9f.31e858","type":"tls-config","name":"","cert":"","key":"","ca":"","certname":"","keyname":"","caname":"","servername":"","verifyservercert":false}]

system · 23 July 2022 07:32

This topic was automatically closed 60 days after the last reply. New replies are no longer allowed.

Topic		Replies	Views
Trigger node question General	3	231	19 December 2020
Global/Context Variables General	7	265	15 January 2023
Context updated automatically? General	6	194	6 March 2023
Variable number in a flow General	11	141	9 August 2024
Saving context - advice requested! FAQs	21	1575	18 July 2020

How to trigger flow when context value change

Related topics