an overview of open devicenet vendor association pmb 499, 20423 state road 7 #f6 boca raton, fl...

An Overview of

Open DeviceNet Vendor Association

PMB 499, 20423 State Road 7 #F6

Boca Raton, FL 33498 USA

©1998, 1999 ODVAAn Overview of

DeviceNet is Positioned at the Device Level


Network Layer Positioning-

F

un

cti

on

alit

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+ Information Level Network

Automation & Control Level Network

Device Level Network

- Cost +

+ C

om

ple

xity -

- Data +

Discrete Process

I/O Control Peer-to-Peer

Sensor Actuator Level

Network


Network Positioning-

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+

EtherNet/IP

- Cost +

+ C

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xity -

- Data +

DeviceNetOther CANSDS

Fieldbus H1Profibus-PAModbusHART

Profibus-DPInterbus-SRemote I/O

Profibus-FMSData Highway+Modbus Plus

ASi, Seriplex, Hardwiring, RS485 etc.

ControlNetFoundation Fieldbus H2


History & Technology

History Base Technology

developed by Allen-Bradley

Introduced March, 1994

Technology transferred to ODVA in April, 1995

Technology CAN messaging

layer 2 (data link layer) - ISO 11898 and 11519-1

DeviceNet is layer 7 (application layer ) and layer 1 (physical layer) designed for industrial automation


Key Benefits

Reduced Wiring and Installation Cost Reduced Start-Up Time Reduced Downtime Removal, insertion and replacement of devices on the

network under power Interchangeability of devices from multiple vendors Rapid Troubleshooting Efficient Communication Configuration of devices over the network (set-up or runtime)


Reduced Wiring and Installation Cost

“DeviceNet eliminates the need to run long stretches of wire or conduit.” Steve Jessup, Maintenance Manager

Rhode Island Beverage

Before DeviceNet After DeviceNet


Reduced Start-Up Time

“We had lead times of 22-24 weeks for getting a production line up-and-running. With DeviceNet, we’re down to 5-6 weeks.” Jeff Kornetzke, Systems Manager

Planar Standish, Inc.


Reduced Downtime

“Using DeviceNet provides valuable diagnostic information to help diagnose and troubleshoot problems before they occur.” Jeff Danielson, Lead Electrician

Black Hills Bentonite


Removal and InsertionUnder Power (RIUP)

“DeviceNet provides us with increased flexibility. As we expand, we can add or remove devices from the system without powering down.”

Dominique Alibeckoff,Director of EngineeringNylonge


Interchangeability of Devices From Multiple Vendors

“DeviceNet products are virtually interchangeable because of the network’s Device Profiles.”

Gary Workman, Staff Development EngineerGeneral Motors


Rapid Troubleshooting

“If we have a problem on a production line, DeviceNet provides a fast and accurate diagnosis -- reducing the time needed for maintenance and troubleshooting.”

Rick Teeny, PresidentTeeny Foods


Efficient Communication

“DeviceNet is a giant step forward in making plant floor information available in real time because it provides faster data processing, more security in data transmission, superior error checking and greater overall flexibility.”

Michael Kreller, General ManagerPriority One Packaging


Configuration of Devices Over the Network

“DeviceNet is the only network that enables us to dynamically add and subtract nodes without network re-configuration.”

Mark Bauwens, EngineerCheesebrough Ponds


Wide Selection of Products

“Because of DeviceNet’s interoperability, we were able to choose best-in-class products at the lowest cost. In fact, our line features more than 60 devices from seven different DeviceNet suppliers.”

Brian Gile, EngineerRaynor Garage Doors

Additional Benefits


Ease of Use

“DeviceNet allows us to access information such as line faults and drive parameters from a single operator terminal.”

Ron Schiepan, Packaging SupervisorLabatt Breweries


Reduced Time and Effort

“DeviceNet has saved us hundreds of hours because we can store presets for our devices.”

Gregory Amos, Director of Systems EngineeringRemstar International Inc.


Other Feedback

“The smallest definable block used with our proprietary network was 32 inputs and outputs, but with DeviceNet we were able to cut it down to only four inputs and outputs.”

– Phil Hamilton, Engineer,Seed & Grain Systems, Inc.

“With DeviceNet’s simple plug connectors, we see a definite savings in both time and effort.”

– Bill Ripley, Controls Engineer, Food Machinery Sales

“DeviceNet eliminated wiring, reduced costs, and improved noise immunity. Its performance was essential in getting us to our final prototype.”

– Mike Macdonald, Executive Vice President, International Submarine Engineering Ltd.


Linear Bus Topology(Trunkline-Dropline)

NodeNodeNodeNode

NodeNodeNodeNodeNodeNodeNodeNode

NodeNodeNodeNode

NodeNodeNodeNode NodeNodeNodeNode

NodeNodeNodeNode NodeNodeNodeNode NodeNodeNodeNode

Power (24Vdc, 8A) & Signal to Power (24Vdc, 8A) & Signal to all devices on a single cableall devices on a single cable

Drop length: 0 - 6 metersDrop length: 0 - 6 meters

Branching & Daisy-ChainBranching & Daisy-Chain


Network Specifications

CumulativeDrop-line Budget156m @ 125Kbaud 78m @ 250Kbaud 39m @ 500Kbaud(Maximum of 6m each)

Trunk line Distanceand Baud rate100m Max. with Thin cable500m @ 125Kbaud (thick)250m @ 250Kbaud (thick)100m @ 500Kbaud (thick)(4Km with Repeaters)

Maximum Devices64 Nodes per Network

Physical Media(Shielded Twisted Pair)Communications and Power•Thick - Trunk wire•Thin - Trunk or Drop

Drop-line wiring•Single drop•Daisy-chaining off drop•Branching off drop

Device ConnectionsT-TapsZero-drop

Terminating Resistors75 Resistors at bothnetwork trunkline ends

Network Power•24vDC power to devices•Thick trunk rated to 8 amps•Thin wire rated at 3 amps

Messaging ServicesProducer/Consumer•High-speed I/O•Programming•Configuration•Diagnostics

ALLEN-BRADLEY

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Network Messaging Services

Multi-master

Cyclic

StrobeChange-of-State

Multicast

Point-to-Point

Peer to Peer

Polling

Broadcast

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Polled I/O Messaging

CTLR1CTLR1 HMIHMI

Drive1Drive1SensorSensor Drive3Drive3Drive2Drive2

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Polling

CTLR2CTLR2


Strobe I/O Messaging

CTLR1CTLR1 HMIHMI


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Strobe

CTLR2CTLR2


Change-of-State I/O Messaging

CTLR1CTLR1 HMIHMI


CTLR2CTLR2ALLEN-BRADLEY

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Change-of-State


Cyclic I/O Messaging

CTLR1CTLR1 HMIHMI

Drive1Drive1TemperatureTemperature

SensorSensor Drive3Drive3Drive2Drive2

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Cyclic

Cyclic Rate100ms

Cyclic Rate200ms

Cyclic Rate50ms

Cyclic Rate25ms

CTLR2CTLR2


Point-to-point Messaging

CTLR1CTLR1 HMIHMI


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Point-to-Point

CTLR2CTLR2


Multi-master Messaging

CTLR1CTLR1 HMIHMI


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Multi-master

CTLR2CTLR2


Multi-cast I/O Messaging

CTLR1CTLR1 HMIHMI


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Multicast

CTLR2CTLR2


Broadcast

CTLR1CTLR1 HMIHMI


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Broadcast I/O Messaging

CTLR2CTLR2


Peer to Peer

CTLR1CTLR1 HMIHMI


CTLR2CTLR2

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Peer-to-Peer I/O Messaging


CTLR1CTLR1 HMIHMI


CTLR2CTLR2

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Hybrid I/O Messaging

Multi-master

Cyclic

StrobeChange-of-State

Multicast

Point-to-PointPeer to Peer

Polling

Broadcast


Typical Sealed-Style Physical Media

Multiport Taps

Tee Taps

Trunk line segments -molded mini-connectors

Drop lines - molded connectors - 0 to 20 ft. - mini or micro at device

Field Installabletrunk lineconnectors

NodeNodeNodeNode

NodeNodeNodeNode

NodeNodeNodeNode

NodeNodeNodeNode

NodeNodeNodeNode

NodeNodeNodeNode

NodeNodeNodeNode

NodeNodeNodeNode

NodeNodeNodeNode


Typical Open-Style Physical Media

Zero drop with temporary terminalsupport Taps may be mounted in panels or

in junction boxes with cord grips

TrunkTrunk

Droplines (0-6 m)Droplines

NodeNodeNodeNode

NodeNodeNodeNode

NodeNodeNodeNode

NodeNodeNodeNode

NodeNodeNodeNode

NodeNodeNodeNode

NodeNodeNodeNode

NodeNodeNodeNode

NodeNodeNodeNode


IDC Module Tap& Flat Wire

Module Top

Flat Media with Insulation Displacement Connectors

Two retentive screws for driving blades through cable

“Snap-on” connection

Mechanically-keyed4-wire flat cable

Four through-holes(only two shown) for mounting entire assembly


CAN (Controller Area Network) CAN is open technology supporting multiple applications Chips available today from multiple suppliers

Intel, Motorola, Philips/Signetics, NEC, Hitachi, Siemens

Volumes from multiple industry usage insures downward price pressure

over 97 million chips sold in 1998 over 137 million forecasted by 2000 (CAN in Automation) 100 to 10,000 times the volume of other industrial ASICs

Currently in use in automobile environment today an excellent proxy for industrial applications temperature extremes, high noise environment used in critical control loops (ABS braking)


CAN Sales 1997-2002

173

149

137

123

97

60

0204060

80100120140

160180

Un

it S

ales

(in

Mill

ion

s)

19

97

19

98

19

99

20

00

20

01

20

02

Source: CAN Newsletter, June 1999

Data Frame

Broadcasts 0 to 8 bytes of data with identifier

Non-Destructive Arbitration• Similar to Ethernet, each node attempts to transmit when the

network is free.• Unlike Ethernet, there is no collision. The “winning” node

continues to transmit its message to completion• This mechanism GUARANTEES that NEITHER information

NOR time is lost !!• The value of the Identifier defines priority during arbitration• No two Identifiers are alike

MessageMessageIdentifierIdentifierS

tart

AckControl DATA (0-8 bytes) CRC

The CAN Message Protocol


Arbitration Example

0 0 0 1 00000001 xxxx 01EOF

10110110100 0

Node 1 Transmits:

As seen on the wire:

0 0 0 1 00000001 xxxx 01EOF

10110110100 0

Node 2 Transmits:

0 10110111

Node 2 losing arbitrationand stops transmitting!

Node 2 still ACKs message.

01

Arbitration Field


The Next Generation Networking Paradigm:

Producer/Consumer


Two Communication Models

Source/Destination (point to point)

synchronized action between nodes is very difficult as data arrives at a different time to each node wastes bandwidth as data must be sent multiple times when only the destination is different

Producer/Consumer (the data is identified)

multiple nodes can consume the same data at the same time from a single producer nodes can be synchronized more efficient bandwidth usage

src dst data crc

identifier data crc


Source/Destination Example...

One person (“source”) tells each person (“destinations”) in the room, one at a time, the

current time of day (data) People may choose to ignore, but time and

effort is wasted Time will pass as the “source” communicates to

each “destination”, one by one

Delivery time changes with thenumber of people in the room


Source/Destination Limitations Requires multiple packets to deliver the same

message to multiple devices Data arrives at different times to different

destinations Puts pressure on network bandwidth Results in the use of different networks for

messaging and time-critical I/O


Producer/Consumer ExampleOne person states (“produces”) the current time of day

(data) once to one or more people (“consumers”) All people hear the data simultaneously Some people may choose to listen to

(“consume”) the data (acknowledgeby nodding, adjust their watch, etc.)

Others may choose to ignore(“not consume”) the data

Highly deterministic(delivery time consistent ifmore people enter or people leave the room)


Producer/Consumer (example 2)

message #1 position reference from Sensor multicast to Controller 1, Controller 2, and

HMI

message #2 speed command from Controller 1 is multicast to all Drives 1, 2, & 3, and HMI

multicast less efficient with source/destination peer to peer requires 7 messages vs. 2

Drive1Sensor

Drive3Drive2

#1#2

Controller 1Controller 2

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HMI


Producer/Consumer Networks can support many communication relationships Polling Cyclic Change-of-State (COS) Combinations Master/Slave, Multimaster, Peer-to-Peer One-to-One, Multicast, or Broadcast


Producer/Consumer - Benefits Simplifies programming

No controller data management required for non-control functions (e.g., Operator Interface during fault diagnosis)

Improves throughput Network not filled with old data (e.g., sensor status)

Provides more timely responses Data communicated only as needed, one time (e.g., error conditions)

No additional cables required Control AND programming AND diagnostics over the same network

Improves Productivity Engineering, Installing, Maintaining, etc.


Which Networks Support Which Model? (Examples)

Source/Destination - “the old paradigm” - Ethernet - Profibus (DP, PA, FMS, ...)

- Interbus S - Seriplex

- Modbus - Modbus Plus

- Remote I/O - Data Highway Plus

Producer/Consumer - “the new paradigm” Foundation Fieldbus ControlNet DeviceNet EtherNet/IP


Others using Producer/Consumer Sun Microsystems - Java API’s (“InfoBus”) use

Producer/Consumer allowing interoperable applets on a Web page to communicate with each other Source: NetworkWorld, 20-Oct-97

Microsoft - “… threads have a producer-consumer relationship (actively cooperating on a common goal) rather than a mutual exclusion relationship (trying to avoid conflicts while sharing a common resource).”Source: www.microsoft.com, 27-Oct-97


EtherNet/IP

Extends commercial off-the-shelf Ethernet with an open, industrial protocol for automation purposes

Based on encapsulated ControlNet and DeviceNet messages inside TCP/UDP/IP protocol

Provides explicit (request/response) and implicit (real-time I/O data) messaging

Configuration of multiple DeviceNet networks from a single PC on Ethernet

Simple routing between DeviceNet and Ethernet Supported by ControlNet International, Industrial

Ethernet Association and ODVA Visit the EtherNet/IP section of the ODVA Web site

(www.odva.org) for additional information


Multi-Vendor Interoperability using Published Device Profiles

Vendor A Vendor B Vendor C

start/stop start/stop start/stop

fwd/rev fwd/rev fwd/rev

accel/decel accel/decel accel/decel

power calc. power calc. power calc.

Vendor A Vendor B Vendor C

other eng. units foreign lang. (none)

temp. calc.

AC Drive Profile (example)

Vendor Value-Add

Published in Spec.


Open DeviceNet Vendor Association Mission Manage DeviceNet Technology

Publish Specifications Publish Test Software, Run Test Centers Provide a forum for directing the future of DeviceNet

technology and products

Provide DeviceNet Tools and Services for Users and Systems Integrators

Pursue International Standardization Reduce Vendor Time-to-Market Promote DeviceNet

Manage common marketing efforts of group members


All ODVA Members manage DeviceNet technology

Any vendor can join ODVA and participate in the Special Interest Groups (SIGs)

SIGs contribute enhancements to the DeviceNet Specifications

Big companies and small companies have equal say

ODVA bylaws protect non-obsolescence


ODVA has a global presence

ODVA

Test LabU of Michigan

Test LabU of Warwick

ODVAJapan

ODVA NewZealand

ODVAAustralia

ODVAChina

ODVAKorea

ODVA Europe

Test LabASTEMJapan

DeviceNetUK

Special LabTexas A&M


Five Years of Membership Growth

74

112

136163

207

243274

293 307

323

0

50

100

150

200

250

300

350Q

3'95

Q1'

96

Q3'

96

Q1'

97

Q3'

97

Q1'

98

Q3'

98

Q1'

99

Q3'

99

Q1'

00


Membership

Over 300 member companies worldwide– ABB, Allen-Bradley, ASCO/Joucomatic, Banner,

Beldon, Cutler-Hammer, Festo, Fischer-Rosemount, Hitachi, Mitsubishi, Nematron, Omron, Parker Hannifin, Pepperl+Fuchs, Reliance, Schneider Electric, SMC, SST,Toshiba, Turck, Wonderware, etc.

Over 100 SI/OEM members– Alvey, Jervis B. Webb, KR Automation, Rapistan

Demag, ...


Association Services

Maintain Vendor ID Registry Operate Independent Test Labs Provide Training for Developers and Implementers Information Source (Literature Fulfillment, Telephone

Referrals to Experts) Resolve multi-vendor product malfunctions and

adjudicate non-conformance issues Web Site: www.odva.org Dr. DeviceNet (free technical support)


ODVA Tools DeviceNet Network Monitor Detect shorts Monitor voltage levels;

indicate high or low voltage conditions

Auto-detect bus speeds; indicate 125,250 0r 500 kbps

Monitor bus traffic and identify Group 1, 2, 3 and 4 traffic

Detect and indicate error frames


System design tool does power and distance limit checks Selects cable components; auto-generates bill-of-material

ODVA Tools DeviceNet Assistant


New ODVA Training Services

DeviceNet University 2-day hands-on multi-vendor user training held at

various locations throughout North America Teaches students the correct way to install and

troubleshoot DeviceNet For locations and dates, visit the ODVA Web site

(www.odva.org)


ODVA Publications

• Product Catalog (Print, CD ROM and Web)• Specifications (Print and CD ROM)• Newsclips• DeviceNet News Newsletter


Introducing the Redesigned Web Site


www.odva.org

DeviceNet Product Catalog Technical Overview Downloadable Technical Presentations and

Papers Links to Related Sites (Members, Bus

Technical Information) E-mail links to experts Member information, contacts


Dr. DeviceNet Free technical service

Design Installation Application Troubleshooting

Available to anyone ODVA has 12 volunteer DeviceNet experts around

the world to provide support e-mail to [email protected] or go to web

site www.odva.org Reply from DeviceNet expert in 24-48 hours


Five Years of New, Innovative Products

52

128

166

283

350

367

0

50

100

150

200

250

300

350

400M

ar-

95

May-9

6

Jan

-97

May-9

8

Jan

-99

Mar-

00


Products AvailableSensors

Valves

Motor Protection/Control

AC/DC drives

I/O

PLCs

PC Interfaces

S/W products

HMI

Developers’ Tools

many others


Certification MarkCertification Mark


Gary Workman Quote on Conformance Testing

"Open systems create a competitive marketplace which is advantageous to the end user. However, if products aren't interoperable and interchangeable, it's a moot point," said Gary Workman of GM, explaining the rationale behind the new policy that GM North American Operations will only purchase conformance tested products.


Five Years of Escalating Node Counts(and several years of node count limbo)

Nu

mb

er o

f In

stal

led

No

des

-

150,000

300,000

450,000

600,000

750,000

Q3'95 Q1'96 Q1'97 Q1'98 Q1'99 Q1'00

???


Market Report

By the year 2001, 47% of end users indicate they will purchase DeviceNet (up from 39% today).

– Source: Control Engineering survey, March 1999

A majority of end users and OEMs surveyed have chosen DeviceNet over other networks.

– Source: Venture Development Corporation research study, 1998

Worldwide revenue in the industrial networking market will reach $2.8 billion by the year 2003 (up from $1.9 billion in 1998).

– Source: Industrial Controls Intelligence & the PLC, April 1999

Twenty-four percent of all devices (29 million) will interface with industrial networks by 2002.

– Source: Control Magazine, June/July 1999


Industries & Applications

Automotive Food & Beverage Material Handling Packaging High-speed Assembly Pulp & Paper Semiconductor Fabrication


Key Customers

John Deere LaFarge Cement Motorola Nestle Pepsi Proctor & Gamble Philip Morris Quaker Oats Ralston-Purina

Anheuser-Busch Applied Materials Baxter Healthcare Caterpillar DuPont General Motors Giddings & Lewis Heineken Hershey Foods


Best Opportunities for DeviceNet

“Greenfield” w/designed-in features Retrofits where time-out-of-service is

valuable; any project where time is critical Acceptance Test on system house floor

required or beneficial Field changes are anticipated Device diagnostics are needed for

increased system uptime Post-installation service call is costly


http://www.odva.orge-mail: [email protected]

(954) 340-5412

(954) 340-5413 fax

for more information, contact:


Frequently Asked Questions


Is DeviceNet maximum distance long enough?

DeviceNet’s maximum distance is 500 m (1,640 ft). Is that long enough?

Typical device level installations are smaller than an average automobile. Yes, 500 m is long enough. For the non typical installations, fiber optic repeaters are available to extend the distance up to 4 km.


How does DeviceNet integrate with existing control systems?

DeviceNet can be integrated with many existing control systems using the existing PLC based controllers or off the shelf gateway solutions. In fact, the top 6 global PLC vendors support the integration of DeviceNet with their PLCs. Additionally, off the shelf gateway products are available to integrate DeviceNet with many proprietary plant protocols.


Is DeviceNet fast enough?

DeviceNet’s fastest speed is 500 Kbaud. Is that fast enough?

Maximum throughput should be a measure of 3 factors: Network Model, Protocol Efficiency, and baud rate.

Network Model has the greatest impact on maximum throughput as it defines how information is distributed across the network. Examples of network models include the source / destination model and the modern producer / consumer model. Examples of producer / consumer models used today include DeviceNet, ControlNet, Fieldbus Foundation, Sun Microsystems Infobus, and Microsoft software (threading).

Protocol efficiency is the measure of network overhead when sending data on the wire. Standard polling (scanning) of all connected nodes has a fixed efficiency and is usually not flexible. DeviceNet allows the use of standard polling but also allows Change of State (COS) and cyclic (timed interval) which can dramatically reduce network traffic, thereby lowering the I/O scan time and improving the network efficiently.

The last measure of throughput is Baud Rate. Baud Rate defines how quickly data travels on the network from one point to another point.

With DeviceNet’s producer / consumer model and efficient protocol options, DeviceNet works smarter rather than working harder. With the combination of the producer / consumer model and efficient protocol options, DeviceNet’s 500 kbaud is fast enough for device level applications.


Definition of Determinism

Determinism:1. The ability to calculate with certainty, within a defined limit or

range of time, when data is sampled, produced, delivered or made available to other networked nodes.

2. The ability to maintain a stable data production rate regardless of other variations of traffic (e.g. addition of nodes, increase in data size) on a network.

3. Ability to calculate with confidence the worst-case schedule for when data will be accessible to other devices in a system.

Increases in traffic typically result in a reduction of network determinism.


DeviceNet Determinism

DeviceNet can be very deterministic when certain criteria is met with the network configuration. In order to maintain a high degree of determinism, it is necessary to control the production of data on a network while minimizing any collisions of data production from other nodes.

Criteria for maximizing DeviceNet determinism: Polled System (High Determinism):

Single-master network configured as Master-Slave/Polled system. Master controls all data requests and data production to/from all slave devices. Network node count and message length from each node fixed. Variables (e.g. adding of nodes, adjustments to message length) are minimized.

Variable introduced will impact range of determinism in the system. Cyclic System (Limited Determinism):

Network is configured using only cyclic devices. Network node count and message length from each node fixed in size. Data collisions are minimized via a fixed data production schedule for nodes. Variables (e.g. adding of nodes, adjustments to message length) are minimized.

Variable introduced will impact range of determinism in the system.

an overview of open devicenet vendor association pmb 499, 20423 state road 7 #f6 boca raton, fl...

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