Project Engineer James Condon led a presentation on Siemens PLC Industry 4.0. The presentation covered how Industry 4.0 can offer better efficiency for existing industrial equipment.

1. Taking Your Siemens
PLC to Industry 4.0
James Condon, DMC
usa.siemens.com/summitUnrestricted © Siemens 2019

2. Unrestricted © Siemens Industry, Inc. 2019
Page 2
2019 Automation Summit
• Title: Taking Your Siemens PLC to Industry 4.0
• Track: BPNA
• Presenter: James Condon
• Company: DMC
• Session # (for your survey): 14.3

3. Unrestricted © Siemens Industry, Inc. 2019
Page 3
James Condon
Project Engineer
• BS Mechanical Engineering
• University of Illinois, Urbana-Champaign
• With DMC since 2011
• Chicago 2011-2015
• Denver 2015-Present
Presenter Info

4. Unrestricted © Siemens Industry, Inc. 2019
Page 4
DMC Overview
Established in 1996, offices in Chicago, Boston, &
Denver and customers throughout the world
Established in 1996, DMC serves customers worldwide from offices in
Chicago, Boston, Dallas, Denver, Houston, New York, Seattle, and St. Louis
employees & growing
170+

5. Unrestricted © Siemens Industry, Inc. 2019
Page 5
DMC has the highest number of S7 certified engineers in the
US.
Siemens Expertise
35+

6. Unrestricted © Siemens Industry, Inc. 2019
Page 6
DMC Customers

7. Unrestricted © Siemens Industry, Inc. 2019
Page 8
Agenda
• What is Industry 4.0 and why
should I be interested?
• I4.0 case study with Agri-
Inject‘s Reflex Connect
product line
• Overview of DMC‘s S7-1200
Industry 4.0 technology stack
• Deep dive into DMC‘s MQTT
S7-1200 driver

8. Unrestricted © Siemens Industry, Inc. 2019
Page 9
What is the internet of things?
• The interconnection via the Internet of computing devices embedded in
everyday objects, enabling them to send and receive data
• Adding internet to things because we can and it makes our lives easier
(maybe)

9. Unrestricted © Siemens Industry, Inc. 2019
Page 10
Industry 4.0, X.0, IIoT and other buzz words
• Industrial equipment already has the capability of communicating to
external devices
• Typically a local HMI or other PLCs used in the process
• Higher level SCADA are now often used to tie together multiple PLCs
• Industry 4.0 is a broad term, but generally refers to allowing machines to
communicate beyond their local area (on some kind of interconnected
network, if that’s a thing that exists)
• Often this is still a SCADA system used to control multiple sites
• Either an off the shelf product (e.g. WinCC OA/7) or a custom solution
(we’ll see one later)

10. Unrestricted © Siemens Industry, Inc. 2019
Page 11
Why should I be interested in Industry 4.0?
• Data availability from controllers
• Data analytics platforms, such as MindSphere, are
becoming more accessible and we should be taking
advantage of their capabilities
• OEE dashboards, finding weak spots in manufacturing
processes, better predictive maintenance
• For geographically distributed systems, being able to
react faster to alarms
• Being able to re-supply sites only when needed rather
than spending time doing periodic visits, which are not
all needed

11. Unrestricted © Siemens Industry, Inc. 2019
Page 12
Why should I be interested in Industry 4.0?
Better data coverage!

12. Unrestricted © Siemens Industry, Inc. 2019
Page 13
Why should I be interested in Industry 4.0?
• Get better efficiency out of existing equipment
• As data analytics dictates needs for parameter updates, those updates can be applied in real
time
• Speeds up the cycle of analyze data, identifying problems, creating an update, and
implementing the changes
• For geographically distributed systems making any update remotely can be a significant time
saving over having to get to the controller location

13. Unrestricted © Siemens Industry, Inc. 2019
Page 14
Agri-Inject Case Study
• Company Overview
• Problems their customers face
• Solution overview
• End customer benefits
• Or why this is a more useful product than an IoT diaper

14. Unrestricted © Siemens Industry, Inc. 2019
Page 15
Agri-Inject Company Overview
• Located in Yuma, CO
• Specializes in fluid injection pumps
• Size range from 1.25 gph to 150 gph
• Can be used for residential, agricultural, and industrial applications

15. Unrestricted © Siemens Industry, Inc. 2019
Page 16
Reflex Connect Justification
• For agricultural fertilizer injectors, they can often be distributed over hundreds of square miles.
• To make adjustments to fertilizer usage, it can take all day to visit each site to make adjustments
• The only way to gather alarm information from a fertilizer injector is to visit the site

16. Unrestricted © Siemens Industry, Inc. 2019
Page 17
Reflex Connect Solution
• Field Control Panel
• S7-1200, Comfort Panel, and
Cell Modem
• Azure
• MQTT Broker, API, SQL
Database, ReactJS front end
website
• End user
• Browser

17. Unrestricted © Siemens Industry, Inc. 2019
Page 18
Reflex Connect Solution

18. Unrestricted © Siemens Industry, Inc. 2019
Page 19
What is different about DMC’s solution?
MQTT
• Message Queuing Telemetry Transport
• First created in 1999
• Widely adopted
• AWS, Azure, Google Cloud, MindSphere
• Libraries already exist for python, C++, .NET and more
• Lightweight and fast

19. Unrestricted © Siemens Industry, Inc. 2019
Page 20
PLC to Database Connection
• Traditional polling steps
• Open TCP connection
• Send query against API
• Receive response, often there will
be no changes
• Close TCP connection
• Wait
• Repeat
ServerPLC
Any new data?
Nope
Any new data?
Nope
Any new data?
Yes, here it is

20. Unrestricted © Siemens Industry, Inc. 2019
Page 21
Why you should use MQTT over traditional polling
ServerPLC New message
• MQTT communication steps
• Open TCP and MQTT
connection
• Listen for updates
• Benefits of MQTT
• Uses less bandwidth
• Faster

21. Unrestricted © Siemens Industry, Inc. 2019
Page 22
What else goes into MQTT?
• Current version is 3.1.1, documentation is available at http://mqtt.org/documentation
• A basic exchange is shown below
• More message types available (e.g. ping/ping response)
ServerClient
Connect
Connect acknowledge
Publish Topic B
Publish Topic A
Subscribe to Topic A
Subscribe Acknowledge

22. Unrestricted © Siemens Industry, Inc. 2019
Page 23
PLC Library
• Made up of 1 function block, 1 data block, and 2 functions
• fbMQTT
• Two state machines
• Sending data (also manages the TCP connection)
• Receiving data
• fcSerializeData
• Takes a topic name and data, enqueues it into the message buffer
• fcDeserializeData
• Takes a topic name and an ANY, checks the receive buffer for messages that
match its topic name
• dbMqttData
• Holds buffer for outgoing messages and slots for receiving messages

23. Unrestricted © Siemens Industry, Inc. 2019
Page 24
What can we do with Industry 4.0?
Monitoring

24. Unrestricted © Siemens Industry, Inc. 2019
Page 25
What can we do with Industry 4.0?
Data Logging

25. Unrestricted © Siemens Industry, Inc. 2019
Page 26
What can we do with Industry 4.0?
Control

26. Unrestricted © Siemens Industry, Inc. 2019
Page 27
What can we do with Industry 4.0?
Alarming

27. Unrestricted © Siemens Industry, Inc. 2019
Page 28
What can we do with MQTT, Siemens PLCs, and Industry 4.0?
• Overall, it opens up possibilities for monitoring and
control of remote systems from PLC
• Eliminates need for 3rd party gateways or
VPN/VLAN solutions for remote access of data
• By linking up the MQTT broker with an API, it
opens up possibilities to be able to monitor and
control a PLC remotely (e.g. web sites or native
mobile applications)

28. Unrestricted © Siemens Industry, Inc. 2019
Page 29
Your Benefits
• This PLC MQTT library is open source and available at https://github.com/jcondonDMC/SiemensMQTT.
Features include
• Publishing data with QoS 0 and 1
• Subscribing to 10 topics and receiving data (this is arbitrary and could be changed depending on
available memory)
• Runs on S7-1200 and S7-1500
• Supports user authentication

29. Unrestricted © Siemens Industry, Inc. 2019
Page 30
Why you shouldn’t use MQTT on a Siemens PLC
• Currently no bidirectional native MQTT communication instructions are available
• Open TCP communication blocks are available.
• DMC created an MQTT communication library capable of serializing/deserializing
raw PLC data
• On the Mindsphere road map!
• PLCs are not good at parsing strings and the traditional payload of MQTT
messages is JSON
• The PLC library that DMC wrote pairs with a .NET MQTT broker in the cloud that
can interpret and create raw byte arrays of PLC data

30. Unrestricted © Siemens Industry, Inc. 2019
Page 31
What’s Next
• Add in encryption
• Currently encryption is achieved through a VPN connection with the cell modem
• Memory optimizations
• Add in QoS 2 for publishing and receiving data
• Create Mindsphere solution when bidirectional communication is available

31. Unrestricted © Siemens Industry, Inc. 2019
Page 32
Your Benefits
• Drink Bot MQTT integration
• Since the library is robust and extensible it was easy to apply to Drink Bot
• Order drinks with Alexa
• Reporting of consumed drinks and dashboards
• Nearly identical technology stack as Agri-Inject
• Azure hosted SQL database, API web-service, and front end web-service
• With Agri-Inject, only the front end web-service used the API, but the API is just a set of HTTPS
endpoints that can be easily used by other services such as Alexa

32. Unrestricted © Siemens Industry, Inc. 2019
Page 33
Your Benefits

33. Unrestricted © Siemens Industry, Inc. 2019
Page 34
Title of your presentation here
Name: James Condon
Company: DMC
Email: james.condon@dmcinfo.com
Phone: 303 223 1801
Session # (for your survey): 14.3

34. Unrestricted © Siemens Industry, Inc. 2019
Page 35
DMC’s S7-1200 Industry 4.0 Solution
• Field Control Panel
• S7-1200 and Cell Modem
• Cloud - Azure/AWS
• MQTT Broker, API, SQL Database, ReactJS front end website
• End user
• Browser

35. Unrestricted © Siemens Industry, Inc. 2019
Page 36
What else goes into MQTT?
• Current version is 3.1.1, documentation is available at http://mqtt.org/documentation
• A basic exchange is shown below
• More message types available (e.g. ping/ping response)
ServerClient
Connect
Connect acknowledge
Publish Topic B
Publish acknowledge
Publish Topic A
Publish acknowledge
Subscribe to Topic A
Subscribe Acknowledge

36. Unrestricted © Siemens Industry, Inc. 2019
Page 37
PLC Library
• Made up of 1 function block, 1 data block, and 2 functions
• fbMQTT
• Two state machines
• Sending data (also manages the TCP connection)
• Receiving data
• fcSerializeData
• Takes a topic name and data, enqueues it into the message buffer
• fcDeserializeData
• Takes a topic name and an ANY, checks the receive buffer for messages that
match its topic name
• dbMqttData
• Holds buffer for outgoing messages and slots for receiving messages

37. Unrestricted © Siemens Industry, Inc. 2019
Page 38
fbMqtt
• Send data state machine
• Opens TCP connection and MQTT connection
• Checks message buffer
• If messages are available sends message and waits for confirmation (if QoS 1)
• Receive data state machine
• Checks for incoming publish messages
• Parses topic and payload
• Inserts into appropriate slot in the receive message buffer

38. Unrestricted © Siemens Industry, Inc. 2019
Page 39
Serialize Data
• Takes topic name and pointer to a datablock structure
• Serializes the structure to a byte array and inserts the byte array and topic name
into the next available slot in the send message array. Also sets a flag that this
message is ready to be sent.

39. Unrestricted © Siemens Industry, Inc. 2019
Page 40
Deserialize Message
• Takes topic name and pointer to a datablock structure
• Reserves a slot in the incoming message array
• When fbMqtt receives a message that matches this topic name, it will insert the
message into the incoming message array and set a flag for a new message being
received
• fcDeserialzieMessage will take the byte array from the incoming message array
and serialize it to its pointer

40. Unrestricted © Siemens Industry, Inc. 2019
Page 41
Working with raw PLC data
• Most MQTT data is JSON data, which is easy to read and the receiver of the data
does not need prior knowledge of what the data to contain
• Example: { "name":"John", "age":30 }
• Easy to understand
• Two variables, name and age, with values John and 30
• Without reflection capabilities in a PLC, it’s not possible to dynamically generate
JSON data.
• DMC’s solution is let the broker know about the payload contents in advance
• The server MQTT broker is based db files generated from TIA Portal so that it
can properly parse

41. Unrestricted © Siemens Industry, Inc. 2019
Page 42
Receiving raw PLC data
• When the MQTT broker starts, it checks a folder for .db files and creates a dictionary of classes based on
the contents
• Topic name is based on the file name
• Class properties are generated based on the data block variables
• When a message from the PLC is received, the MQTT broker checks the topic name and grabs the
appropriate class from the dictionary created earlier. Data is then sent to the API and database.
Raw data
API SQL

42. Unrestricted © Siemens Industry, Inc. 2019
Page 43
Sending raw PLC data
• Just as the MQTT broker creates classes for receiving raw data, it will create classes for sending raw data
• When a message from the API is received, the MQTT broker checks the topic name and grabs the
appropriate class from the dictionary created earlier. Data is then
PLC
SQL
Front EndAPI

43. Unrestricted © Siemens Industry, Inc. 2019
Page 44
Title of your presentation here
Name: James Condon
Company: DMC
Email: james.condon@dmcinfo.com
Phone: 303 223 1801
Session # (for your survey): 14.3