This application note demonstrates how to send data from a Siemens S7 Profinet controller to the cloud via MQTT using Node-RED and Revolution Pi. It includes details on required hardware and software components, system architecture, and programming steps to establish communication and data transfer. The document provides technical instructions for users familiar with Linux-based PLC programming and specifies the necessary configurations for MQTT integration.

1. 1
Application Note
__________________________________________________________
Sending Siemens S7 controller data to cloud over
MQTT using Node-Red with Revolution Pi
Version 1.0.0
______________________________________________________________________________

2. 2
© 2021 by UL Electrodevices Pvt Ltd All rights reserved.
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III Floor, S. No. 36,
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Tel.: +91 8956 79 4030
E-Mail: iiot@ulepl.com
revpi@ulepl.com
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improving the documentation.
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the trademarks of companies used and/or mentioned in the present
document are generally protected by trademark or patent.

3. 3
Notes about this Documentation
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Personnel Qualification
The use of the product described in this document is exclusively geared
to specialists having qualifications in Linux based PLC programming,
electrical specialists or persons instructed by electrical specialists who
are also familiar with the appropriate current standards. Moreover, the
persons cited here must also be familiar with all of the products cited in
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contents of these instructions. The sample applications described in this

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documentation represent concepts, that is, technically feasible
application. Whether these concepts can actually be implemented
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Electrodevices Pvt Ltd is not liable for any actual implementation of the
concepts.

5. 5
Table of Contents
Table of Contents...................................................................................5
1. Description.........................................................................................6
2. Used material.....................................................................................6
2.1 Hardware............................................................................................6
2.2 Software..............................................................................................6
3. System Architecture......................................................................... 7
3.1 Block Architecture.............................................................................7
3.2 Real Architecture…...........................................................................8
3.3 Real Connection Screenshot………………………………….….…9
4. Programming...................................................................................10
4.1 Node-Red Flows...............................................................................14

6. 6
1. Description
This application note shows how to send any Siemens S7 profinet
controller data to cloud over MQTT using Revolution Pi with Node-Red
2. Used Material
2.1 Hardware
Provider Sr.
No.
Product Details Orde Code Quantity
KUNBUS 1 RevPi Connect 100274 1
LUTZE 2 SMPS 24VDC 722754 1
SIEMENS 3 S7-1200 PLC
CPU 1212C
AC/DC/RLY
6ES7 212-
1BE40-
0XB0
1
HELMHOLZ 4 REX 250 as
switch
700-878-
UMT01
1
2.2 Software/Utilities
➢ TIA Portal v15.1
➢ Node-Red
➢ node-red-contrib-s7comm library
➢ Advance IP Scanner
➢ Web Browser (Google Chrome)
➢ MQTTlens
➢ HIVEMQ cloud MQTT Broker

7. 7
3. System Architecture
3.1 Block Architecture

8. 8
3.2 Real Architecture

9. 9
3.3 Real Connection Screenshot
The Programming PC, RevPi Connect and Siemens S7-1200 PLC
connected in the same network using Helmholz REX 250 in 3 Different
LAN port of it.

10. 10
4. Programming
We are using node-red-contrib-s7comm A Node-RED node to
communicate with Siemens S7 PLCs .
Node-RED node-red-contrib-s7comm node is designed to communicate
with a SIMATIC S7-300/1200/1500 PLC of SIEMENS based on the
RFC1006-communication protocol. The S7comm node can build up a
connection with the SIMATIC-S7. Furthermore, it can Read/Write
Addresses of the PLC with specific S7-Datatype.
To Establish the communication with Siemens S7 PLCs we need IP
address, Port No, Rack and Slot number as shown in below Image. After
setting connection parameter you can read and write the memory
addresses of the PLC with specific to S7-Datatype same is shown in
below image under Signals

11. 11
Once you read data from PLC now you can use MQTT nodes to send
that data to any cloud over MQTT. Only things we need to have is
MQTT broker address. In this application note we are using HIVEMQ
public MQTT broker address and sending data on PLC_1/Motor topic
Now, To check the data on cloud over MQTT we are using MQTTlens
browser based application as MQTT client or subscriber.
➢ Installing MQTTlens in Chrome.
➢ Open the MQTTlens
➢ Give connection Name
➢ MQTT Broker address and Port Number
And click on CREATE CONNECTION Button. As shown in below
image.

12. 12
After creating connection you can subscribe and publish the data on the
topics
We have now subscribed the topic PLC_1/Motor

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After Subscribing the topic we will get the data which is being published
on the topic (i.e. data from Siemens S7-PLCs). In below Image The
“value”:[false] and “value”:[true] is actual status Q0.0 in Siemens
PLC which is being received by MQTT client Over Internet.

14. 14
Use below Json to use this program readily
[{"id":"9555a608.bdef78","type":"tab","label":"S7 PLC data to
MQTT","disabled":false,"info":""},{"id":"eda5b488.0567e8","typ
e":"s7comm
read","z":"9555a608.bdef78","connection":"3622a876.d4faf8","pa
yload":"{"S7_Type":"Q","S7_DBnum":"0","S7_Datatype"
:"X","S7_Offset":"0","S7_BitOffset":"0","S7_Quantity":
"1","S7_Name":"lamp"}","s7Name":"lamp","topic":"","nam
e":"","signalSetted":false,"none":"true","repeat":"","once":false,
"x":320,"y":20,"wires":[["135afe7f.0180d2"]]},{"id":"a328b28e.5b
605","type":"s7comm
write","z":"9555a608.bdef78","connection":"3622a876.d4faf8","p
ayload":"{"S7_Type":"M","S7_DBnum":"0","S7_Datatype
":"X","S7_Offset":"0","S7_BitOffset":"1","S7_Quantity"
:"1","S7_Name":"button_2_hmi"}","s7Name":"button_2_hmi
","topic":"","name":"","signalSetted":false,"x":351,"y":281,"wir
es":[["3b5f3fb0.141af"]]},{"id":"3b5f3fb0.141af","type":"debug",
"z":"9555a608.bdef78","name":"","active":true,"tosidebar":true,
"console":false,"tostatus":false,"complete":"false","x":561,"y":36
1,"wires":[]},{"id":"135afe7f.0180d2","type":"mqtt
out","z":"9555a608.bdef78","name":"","topic":"PLC
1/Motor","qos":"","retain":"","broker":"7431e2cf.3dd69c","x":5
50,"y":20,"wires":[]},{"id":"1ba4da5d.e9b336","type":"mqtt
in","z":"9555a608.bdef78","name":"","topic":"PLC
1/Motor","qos":"2","datatype":"auto","broker":"7431e2cf.3dd69
c","x":270,"y":100,"wires":[["29b92629.99272a"]]},{"id":"29b926
29.99272a","type":"debug","z":"9555a608.bdef78","name":"","a
ctive":true,"tosidebar":true,"console":false,"complete":"false","x
":590,"y":100,"wires":[]},{"id":"523d22cb.1fadfc","type":"ui_but
ton","z":"9555a608.bdef78","name":"","group":"8aa3fc07.43f25"
,"order":0,"width":0,"height":0,"passthru":false,"label":"Turn
Off

15. 15
DO_1","tooltip":"","color":"","bgcolor":"Red","icon":"","paylo
ad":"{"value":[false]}","payloadType":"json","topic":"","x":17
1,"y":401,"wires":[["a328b28e.5b605","6b5ec5b3.00c9ec"]]},{"id":
"7d89600b.9fd55","type":"ui_button","z":"9555a608.bdef78","na
me":"","group":"8aa3fc07.43f25","order":0,"width":0,"height":0
,"passthru":false,"label":"Turn On
DO_1","tooltip":"","color":"","bgcolor":"Green","icon":"","pay
load":"{"value":[true]}","payloadType":"json","topic":"","x":1
71,"y":361,"wires":[["a328b28e.5b605","6b5ec5b3.00c9ec"]]},{"id
":"6b5ec5b3.00c9ec","type":"ui_led","z":"9555a608.bdef78","ord
er":2,"group":"8aa3fc07.43f25","width":0,"height":0,"label":"S-7
PLC
Q0.0","labelPlacement":"left","labelAlignment":"left","colorFor
Value":[{"color":"#ff0000","value":"{"value":[false]}","valueTy
pe":"json"},{"color":"#008000","value":"{"value":[true]}","val
ueType":"json"}],"allowColorForValueInMessage":false,"shape":
"circle","showGlow":true,"name":"","x":561,"y":261,"wires":[]},
{"id":"6f7076ee.7488f8","type":"inject","z":"9555a608.bdef78","
name":"","topic":"","payload":"","payloadType":"date","repeat
":"15","crontab":"","once":false,"x":90,"y":40,"wires":[["eda5b
488.0567e8"]]},{"id":"3622a876.d4faf8","type":"s7comm","z":"",
"ip":"192.168.10.2","port":"102","rack":"0","slot":"1","payload
":[{"S7_Type":"Q","S7_DBnum":"0","S7_Datatype":"X","S7_O
ffset":"0","S7_BitOffset":"0","S7_Quantity":"1","S7_Name":"la
mp"},{"S7_Type":"M","S7_DBnum":"0","S7_Datatype":"X","S7
_Offset":"0","S7_BitOffset":"1","S7_Quantity":"1","S7_Name":
"button_2_hmi"}]},{"id":"7431e2cf.3dd69c","type":"mqtt-
broker","z":"","name":"","broker":"mqtt.contineonx.com","por
t":"41883","clientid":"","usetls":false,"compatmode":true,"keepa
live":"60","cleansession":true,"birthTopic":"","birthQos":"0","b
irthPayload":"","closeTopic":"","closePayload":"","willTopic":"
","willQos":"0","willPayload":""},{"id":"8aa3fc07.43f25","type":

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"ui_group","z":"","name":"Control S7
PLC","tab":"4f1db04a.9f253","order":1,"disp":true,"width":"6",
"collapse":false},{"id":"4f1db04a.9f253","type":"ui_tab","z":"","
name":"Siemens 1200 PLC
data","icon":"dashboard","disabled":false,"hidden":false}]