1. Brad S. Carlberg, P.E. Jim McConahay
Ethernet I/O
Brad S. Carlberg, P.E.
Jim McConahay

2. Co-Presenter: Brad S. Carlberg
Brad S. Carlberg, P.E. is a Consulting Engineer in Richland, Washington. He is a Registered Professional Control Systems Engineer in the states of Alabama and Washington with over twenty-five years experience in industrial automation and Process Control Engineering. Specifically he has experience with Distributed Control Systems and Programmable Logic Controllers combining extensive experience with both Hardware and Software Design, Programming, Implementation and Startup. Brad received his Bachelor of Science in Mechanical Engineering from Washington State University in Pullman, Washington in Brad is a Senior Member of ISA who has been a conference program committee member since 1997.
BSC
Engineering

3. Co-Presenter: Jim McConahay
Jim McConahay, P.E. is an ISA member and holds a BSEE and MBA from Cal Poly University, Pomona California. Has 30+ years design and installation experience in Production and Automation equipment. Jim is a Sr. Field Application Engineer for Moore Industries-International, Inc. concentrating on process control instruments, SCADA, SIS (Safety Instrumented Systems), fieldbus, data concentrators and communications links.

4. Agenda Agenda Physical Layers of Ethernet Protocol Medley
Migration From Cabinet to the Plant Floor
Enhanced Features of Ethernet I/O
Architecture Considerations
Security
Examples of Ethernet Communications

5. OSI Model OSI (Open Systems Interconnect) Model 7 6 5 4 3 2 1
Application
Presentation
Session
Transport
Network
Data Link
Physical 6
“Ethernet” IEEE 802.3x only applies here 5 4 3 2
UTP, STP, Fiber, Coax, etc. 10/100/1000/10G speeds 1

6. What “language” are you talking?? Protocol
OSI Model
Protocols run on top of Ethernet 7
MODBUS, OPC, HTTP, Etc.
What “language” are you talking?? Protocol 6
Presentation 5
Session
Addressing and Handshaking Protocols 4
TCP 3 IP
Ethernet 2
UTP, STP, Fiber, Coax, etc.
Ethernet 1

7. MODBUS/TCP Ethernet/IP FF HSE CIP
Open Standards
Ensure that your Ethernet I/O supports open standards for connectivity: OPC, MODBUS/TCP, Ethernet/IP, HTTP, HSE etc.
OPC
HTTP
MODBUS/TCP Ethernet/IP FF HSE CIP
HMI, PC,
DCS, PLC

8. Ethernet vs. Twisted Pair
Communications Media
Ethernet vs. Twisted Pair
Speed Multiple Protocols over same cable
Plant wiring infrastructure
Non-Proprietary hardware available (lower cost)
Switch advancements have improved determinism
Power over Ethernet
HMI, PC,
DCS, PLC

9. What if the protocols don’t match?
Protocol Gateway
What if the protocols don’t match?
Is there a solution?
Gateway (Protocol Converter) Ethernet to Ethernet Ethernet to Serial
Wireless to Serial/Ethernet
HMI, PC,
DCS,PLC

10. Protocol Converters and Gateways
Protocol Gateway
Protocol Converters and Gateways
The term “gateway” has many meanings. One common definition is a protocol converter.
Sometimes host and legacy systems can only communicate via one particular protocol. Or, instruments may support one protocol but not the one that the host system supports. Gateways can be very effective solutions that connect these two devices. Since Ethernet is “open” gateways are becoming more and more common.
Sometimes people refer to “drivers” as gateways. A driver is essentially a protocol or language translator.

11. Simplified Gateway Example
HART Data Map
MODBUS Data Map
Gateway Internal Mem.
MODBUS Slave
mapping
HART Master
68.6
68.6
MODBUS Master gets new data
HART Device is polled
MODBUS Data Map
Internal Mapping Takes Place

12. Moving from the Cabinet to the Field
• Temperature Considerations 55C vs. 85C operating Temp’s.
• Channel-to-channel, and input-to-output signal isolation
eliminates unpredictable ground loops
• RFI/EMI protection protects against plant noise
• Accuracy, long term stability, and Input/output resolution of transmitters

13. Common I/O Multiplexer
Isolated Channels
Signal Inputs/Outputs
A/D Converter mP
Typical I/O Card Design -single point of failure -isolation
Common I/O Multiplexer
Signal
Input
Signal
Input
Signal
Input
Signal
Input
Transmitter Like Design -isolation -flexibility of input type
A/D
A/D
A/D
A/D mP mP mP mP
Enhanced I/O Design

14. Isolated Channels Plant Floor “Industrialized” Ethernet I/O
Power and Flexibility of PLC’s
Resolution, Accuracy, and Spec’s of Field Transmitters
(Cabinet Mounted)
(Field Mounted)
Plant Floor “Industrialized” Ethernet I/O

15. “Hardened” Plant Floor Switches
High Temp -40 to 85C vs. commercial ~45C
High Vibration Tolerance
RFI/EMI Rejection
Surge Protection
Dual Power Supply Options for UPS Systems

16. Switch Features for the Plant Floor
QoS (Quality of Service) -Packet Prioritization
SNMP (Simple Network Management Protocol)
SMTP Client ( s about network warnings/breaks)
MAC Layer Filtering
IP Layer Filtering

17. Programming should be easy and intuitive; i.e. web based
Set-Ups
Programming should be easy and intuitive; i.e. web based

18. Do you need more than I/O gathering?
Ethernet I/O systems are smarter and more powerful than ever.
Many times PLC’s are used to perform simple control, math and logic functions.
Questions to ask your Ethernet I/O vendor
Does your Ethernet I/O have the ability to perform control and math?
Is the control programming language proprietary? …

19. Is the programming language
Compliant Language
Is the programming language
compliant?
Function Block Diagram (FBD) Example

20. Know your design needs before choosing your Ethernet I/O system
Topology
Know your design needs before choosing your Ethernet I/O system
Peer-to-Host—Star Topology; Bus Topology
Peer-to-Peer
Hybrid—Peer-to-peer and Peer-to-Host
Wireless/Fiber/Copper

21. Dispersed Monitoring & Control Devices
Peer-to-Host System
DCS, PLC or PC with HMI/SCADA (with NET Concentrator System OPC Server)
Ethernet I/O System
Ethernet I/O System
Additional NET Concentrator System Stations or Uplink to Other Hubs or Switches
Ethernet I/O System
Ethernet Switch or Hub
Ethernet I/O System
Dispersed Monitoring & Control Devices
Analog
Direct
Valve
On/Off
Transmitter
Temperature
Positioners
Contact Closure
Relay
Devices
Sensors
Temperature
Pressure
Level
RTD
Thermocouple
On/Off
Proportional

22. (cost savings with traditional I/O cards) Ethernet/Fiber Network
Peer-to-Peer System
(cost savings with traditional I/O cards)
Ethernet/Fiber Network
PAIR 1
Ethernet I/O System
Ethernet I/O System
Ethernet I/O System
PAIR 2
PAIR 3
Ethernet I/O System
Ethernet I/O System

23. Add Wireless…
Wireless Peer-to-Peer/Host Systems 900Mhz or 2.4Ghz – License Free or Licensed
Ethernet I/O System
PAIR 1
PAIR 2
Ethernet I/O System
Ethernet I/O System

24. Security Concerns Firewalls NAT Routers Virus Protection
Physical Security (personnel and Internet Connection)
“Line speed” packet encryption systems

25. Network Architecture Considerations- “Connected”
Networking
Network Architecture Considerations- “Connected”
VPN
Outside Internet Connections Typical
Front Office Network
Most Convenient but Potentially Vulnerable
Router/Firewall
Process Control Network

26. Network Architecture Considerations- “Disconnected”
Networking
Network Architecture Considerations- “Disconnected”
VPN
Front Office Network
Outside Internet Connections Typical
Safer but Inconvenient
No Physical Connection
Process Control Network

27. Case Study #1 One communication loop, multiple bus
Problem:
PAC – Programmable Automation Controller
Ethernet card in PAC backplane – Ethernet TCP/IP
HMI
Ethernet IP and Ethernet TCP/IP
Flow, valves, level sensors / FF
FF FIM; H1 to HSE link – Ethernet IP (not TCP/IP)
Ethernet protocol conflict between FIM and PAC

28. Case Study #1 One communication loop, two bus
Solution:
Add MODBUS TCP to Ethernet IP Protocol Converter
Two way FF protocol conversion with PAC 28

29. Case Study #1 One communication loop, two bus
Optimized equipment for each part of the system
Used protocol converter to make compatible
Lowest cost item in the system
Far less cost than compromise performance of a single vendor solution

30. Case Study #2 Remote ESD for Oil Platform in Gulf
Problem:
Maintenance Boat and Oil Rig Platform pipeline repairs
Repairs involve heavy equipment above seafloor pipelines
If accident event, need system to shut down Production
ESD (Emergency Shutdown Device)
Automatic
Reliable
Two-way verification of link
Off shore
Portable, distance >100 km
Beyond radio links

31. Case Study #2 Remote ESD for Oil Platform in Gulf
Considerations:
No hard line communication links
No ESD = No Drilling ($$$)
Is existing s, Internet and VoIP to shore facilities
Satellite link is reliable on platform
Satellite link is reliable on Maintenance ship
Maintenance ship is very mobile
Easy installation
Transferrable to new ship
Simple, intuitive to operate

32. Case Study #2 Remote ESD for Oil Platform in Gulf
Solution:
Data concentrator on Maintenance boat
Ethernet Communications module
Discrete input/output module
Packaging with switch plus display lamp tree
Data concentrator of Oil Platform
Packaging with switch, klaxon, plus display lamp tree
Connection to control panel
Expansion
Add SCADA to ESD at negligible cost

33. Case Study #2 Remote ESD for Oil Platform in Gulf
Things at the surface can drop onto sea floor pipelines

34. Case Study #2 Remote ESD for Oil Platform in Gulf
Success
Operational upon initial installation, continuous operation
Simple to operate, intuitive.
Reliable. Now hard-wired to control panel circuits.
Satellite signal limited by extreme weather.
Expansion
Can add I/O modules for telemetry on both ends of links; negligible cost.

35. Case Study #3 Expansion of 4-20mA loops
Problem:
Expansion, low budget, needs more 4-20mA channels
Requires more 4-20mA channels now
No budget to replace existing 4-20mA lengthy cable run
Will require still more channels later
Discrete contact requirement arising
Ethernet cable upgrade
Available in the future, not now
Does not want to waste investment in temporary data concentrator when Ethernet cable becomes available in the future

36. Case Study #3 Expansion of 4-20 loops
Solution
Data Concentrator
MODBUS RTU communications at module each site
AIM each output; AOM each output
DIM each discrete input; ROM each discrete output
Increase number of I/O modules, as desired
Increase pairs of data concentrators
Use existing twisted pair cable
Use one twisted pair to carry ‘all’ channels between data concentrators

37. Case Study #3 Expansion of 4-20mA loops
Data Concentrator on a Peer-to-Peer network
Originally MODBUS Communications Link
Currently Ethernet Communications Link

38. Case Study #3 Expansion of 4-20mA loops
Success
Use data concentrators to collect all 4-20mA loops and convert to digital communications.
Increased number of analog channels, and also easily adds discrete channels
Only one twisted pair required
Recreate signal at distant site with no degrading of analog signal (since communication is digital)
Low cost Ethernet upgrade
Swap only the MIM for an EIM communications module
All other modules are same

39. Case Study #4 Wireless HART, MODBUS RTU & TCP/IP
Problem:
Multiple tasks, need to optimize
Tank farm, Wireless HART; multiple sensors, cable expenses
Closed loop room; add sensors, valves plus data concentrator
Host control room—long distance communication link
Different communications media and protocol
Wireless Hart; radio
Data concentrator; analog/discrete I/O; programming
MODBUS
Need protocol converters
Wireless Hart to MODBUS RTU slave
MODBUS RTU master; control loop; MODBUS TCP slave

40. Case Study #4 Wireless HART, MODBUS RTU & TCP/IP

41. “Our View” - Market Trend with Ethernet
Summary
“Our View” - Market Trend with Ethernet
MODBUS/TCP - MODBUS packets encapsulated in TCP/IP frames Reason: Everyone knows MODBUS, open protocol, and already supported worldwide
Ethernet/IP - “Industrial Protocol”, Rockwell released to ODVA (Open DeviceNet Vendor Association) Reason: Open, supports common publisher/subscriber method of comm., section of protocol already supported in open DeviceNet. Uses CIP (Common Industrial Protocol) for real time control.
OPC -OLE for Process Control. Uses Microsoft’s COM/DCOM/ .NET standards for open comm. Reason: OPC can run over any physical medium and is an open, free of charge protocol that both hardware vendors and software vendors have access to. Many supported development tools. Strong backing by OPC Foundation.

42. Market Trend with Ethernet Cont’d
Summary
Market Trend with Ethernet Cont’d
4. HSE - High Speed Ethernet Foundation Fieldbus protocol over Ethernet. Reason: Open protocol, and large organized support base by Foundation Fieldbus vendors and FF org.
Profinet - Profibus Trade Organization’s answer to open communications. It is NOT Profibus over Ethernet!!! Reason: Strong backing by PTO. Can use layer but not restricted to this layer. Can run over modems, WAN’s, VPN’s, as long as it uses TCP/IP addressing.
CIP
- Common Industrial Protocol is being promoted by ODVA (Open Device Vendors Association). Uses a Producer
consumer network philosophy for real time control applications.

43. Questions?
BSC
Engineering
Thank You!