Q3 • 2009
p10 With Great Power
Comes Network Data
p16 Obstacles and Mysteries of
a Wireless Implementation
• 2009
p26 Q2
Diagnostics:
Use What You Have
Q2 • 2009
More Than
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IN09Q3_01_Cover2.indd 8
7/15/09 2:10 PM
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IN09Q3_FPA.indd 4
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INDUSTRIAL NETWORKING
Custom REPRINts
Q3 • 2009
5
COVER STORY
E VA L U AT E 1 2
Use reprints
to maximize
your marketing
initiatives and
strengthen your
brand’s value.
RepRints aRe ideal foR:
n New Product Announcements
n Sales Aid For Your Field Force
n PR Materials & Media Kits
16
IMPLEMENT 16
Wireless:
The Real World
Frustrating Obstacles and
Unexpected Mysteries of a
Wireless Network Project
Aren’t Covered in the Manual
BY ALICE MCWILLIAMS, CHEVRON PHILLIPS
More Than Less Wire
Wireless Networks Have
Benefits Beyond Saving
Money on Cabling Costs
BY DAN HEBERT, PE,
SENIOR TECHNICAL EDITOR
n Direct Mail Enclosures
n Customer & Prospect
Communications/Presentations
n Trade Shows/Promotional Events
n Conferences & Speaking Engagements
n Recruitment & Training Packages
Reprints are a simple way to put
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RESEARCH
20
The Once and Future Network Traffic Cops
Routers and Switches Continue to Manage and Direct Data on the Network
Information Highway
COLUMNS & DEPARTMENTS
7 FIRST BIT
10 BANDWIDTH
With Great Power ...
8 PACKETS
Power to the Field Devices, Right On
24 PRODUCTS
Smart Objects Use Internet Protocol
26 PARITY CHECK
Diagnostics—Use What You Have
Call 866.879.9144
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INDUSTRIAL NETWORKING is published four times annually to select subscribers of CONTROL and CONTROL DESIGN
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IN09Q3_05_TOC.indd 5
C: 60
7/16/09 9:39 AM
IN09Q3_FPA.indd 6
7/15/09 11:08 AM
Industrial Networking
FIRST
f i r s t BIT
bit
Q3 • 2009
Power over Ethernet (POE) is the
relatively new ability to provide low power, along
with data, to devices via standard Ethernet cable.
PoE, however, is not so new that it already
hasn’t been standardized by IEEE. As explained
in this issue’s BandWidth column on PoE, IEEE’s
spec defines the powered device (PD) and the
power sourcing equipment (PSE), a separate
device typically installed in the wiring closet near
or might not be damaged when a higher amount
of power is delivered on a cable.”
The first and most obvious risk of some PoE
products touting the ability to offer power as high
as 95 W per port is the current capacity of the
24 AWG conductors, which in this application
is roughly 500 mA per conductor, explains Eric
Juillerat, president and CEO of Raven Technology
Group (www.raventechllc.com). “Exceeding this
With Great Power ...
the Ethernet switch or hub that inserts dc voltage
onto the twisted pair cable and can be either
an endpoint or a midspan device. An endpoint
PSE contains both the data communication
capabilities and the power-delivery mechanism,
while a midspan only contains the power delivery
mechanism and is inserted in the network between
the non-PoE-capable Ethernet switch and the PD.
This past spring, PhihongUSA (www.phihong.
com) claimed to have developed a PoE midspan
product line capable of offering 95 W of
power per port. The Phihong midspan’s 95 W
theoretically makes it suitable for high-power
applications such as computer workstations,
LCD panels and wireless-access-point arrays.
Phihong says the new midspan provides IEEE
802.3af detection and disconnect, as well as prestandard IEEE802.3at classification, and offers
voltage, current and circuit protection.
Despite its claims of safety and pseudocompliance, this is an example of a manufacturer
reaching outside the realms of standardization and
interoperability to push the envelope. But with
great power comes great capability.
“As long as the IEEE 802.3 standard is followed,
there are no risks, neither from the safety nor
from the data damage point of view,” says Daniel
Feldman, PoE/PoE+ subcommittee technical chair
of the Ethernet Alliance (www.ethernetalliance.
org) and director of marketing for Microsemi
(www.microsemi.com). “Currently, IEEE 802.3
supports supplying up to 12.95 W to the powered
device on Cat. 3 and above cables. The IEEE 802.3at
task force is working to modify IEEE 802.3 so it
supports delivering 25.5 W on Cat. 5 and above
cables, using two pairs of wires. The IEEE 802.3at
standard is being written so it’s feasible to deliver
on a single Cat. 5 cable up to 51 W using four pairs
of wires. It may or may not be safe, and data might
IN09Q3_07_FirstBit.indd 7
7
can present cable failure probabilities,” he says.
“Some speculate that the combination of the
cable and the RJ45 allow higher current ratings.
However, I am not aware of any tests confirming
this officially. I believe that PoE technology in the
future will be capable of higher power, but at this
time it is not practical.”
The risk of high power would be an introduction
of noise into the system via the Cat. 6 cable,
explains Doug Erlemann, business development
manager-cameras for Baumer Group (www.
baumergroup.com). “The 802.3 spec states that
13.5 W are required at the end of 100 m,” he says.
“Our cameras, for example, draw less than 5.5 W.”
The biggest risk is that the power will be used
for driving I/O output channels directly, which
would quickly exceed the current limitation of
IEEE 802.3af, exceed the current capabilities of the
Cat. 5 data wires’ conductors and also introduce
excessive noise to the data lines, explains Joey
Stubbs, PE, PMP, North American representative,
EtherCat Technology Group (www.ethercat.org).
“Keep in mind that the original purpose of PoE
was to power low-wattage electronics such as
Internet telephones, small microprocessors and
LAN access points,” he says. And regardless, 95 W
still is low power and incapable of driving I/O or
pneumatic valves, notes Stubbs.
Organizations that opt for high-power PoE
products are purchasing products that aren’t
standards-based, warns Art Felgate, product
manager, Transition Networks (www.transition.
com). “The forthcoming IEEE 802.3at PoE+
standard will only support at most 30 W,” he
explains. “Ratification of this standard should
occur later this fall. In the long run, those
companies could incur unexpected, higher costs
if they move from the non-standard solutions to
standards-compliant ones.”
Organizations
that opt for highpower PoE products
are purchasing
products that are
not standards-based.
MIKE BACIDORE
MANAGING EDITOR
mbacidore@putman.net
7/17/09 1:42 PM
Industrial Networking
pa c k e t s
Q3 • 2009
Bits & Bytes
GE Global Research (www.
ge.com/research) was
awarded $2 million in federal
stimulus funding from the U.S.
Department of Defense for a
smart microgrid demonstration
project at Twentynine Palms
Base, Calif., the world’s largest
Marine Corps base.
Wurldtech Security
Technologies (www.
wurldtech.com), provider
of the Achilles Platform and
other cybersecurity testing
and certification solutions,
expanded the capabilities of
the Achilles Network Testing
Platform to include test suites
for emerging industrial wireless
protocols.
Rockwell Automation (www.
rockwellautomation.com) and
ProLeiT (www.proleit.com)
reached a global agreement
allowing ProLeiT to more tightly
integrate its Plant iT with the
Rockwell Automation Logix
control platform.
HART Communication
Foundation (www.hartcomm.
org) released its Wireless Test
System, an update to the HART
Test System, a set of testing
tools designed to ensure
interoperability of HARTenabled devices.
Igus (www.igus.com) product
experts are available to
examine cable carriers and
continuous-flex cables free of
charge during plant shutdowns
in August.
The 1 millionth Anybus
communications module was
produced by HMS Industrial
Networks (www.anybus.com).
IN09Q3_08_09_Packets.indd 8
Smart Objects Use Internet Protocol
Interconnected smart objects, the everyday devices around us with embedded
sensors providing information to a host application, “represent a quantum leap in the way technology
will be applied in the coming century,” notes Geoff Mulligan, chairman of the IPSO Alliance (www.ipsoalliance.org), an organization promoting a network that will allow sensor-enabled physical objects to talk
to one another via an Internet protocol for smart objects (IPSO).
A so-called “smart object” is any device that combines processing power, communications capabilities
and a power source to provide real-time information to a computer system. Integration of the Internet
protocol, which allows the Internet to run smoothly, in turn allows smart objects to communicate
directly with one another over the
existing global network following a proven
protocol that has been in place for nearly
35 years. The IP framework additionally
provides scalability, a vital feature for large
organizations.
One particularly notable aspect of
this organization’s mission is that the
technology exists today. The standards
do not provide a future plan for what
will be accomplished in the next year
or decade, but rather what is here now.
IPSO Alliance demonstrated interoperability by linking
An organization wishing to deploy this
global sensors to a graphical application display at a
technology can do so immediately and
recent trade show. More than 100,000 readings from
with confidence that the infrastructure
sensors spread throughout Korea, Finland, Sweden,
of the network will be around in the
Switzerland, Canada, the U.K. and the U.S. were collected.
foreseeable future.
New member organizations include such familiar names as Intel, Bosch and Johnson Controls, along
with more specialized tech and wireless firms CEA, Convergence Wireless, ECE, Ember, IAR Systems, Ibit
World, INRIA, Maxfor, National Semiconductor, Somfy, Tridium and ZeroG Wireless rounding out the
latest group of companies to join the organization.
These new members bring IPSO’s corporate membership to 51, joining companies such as Cisco,
Ericsson, SAP, Sun Microsystems and Texas Instruments.
“Intel believes the IPSO Alliance will be an integral group to enable the interoperability and
connectivity of devices for the embedded Internet,” says Tony Neal-Graves, general manager, strategic
planning, embedded and communications group, Intel (www.intel.com). “Intel architecture has played a
central role in the build-out of the Internet, and we’re committed to delivering products and technology
that will enable billions of embedded, connected devices.”
A need exists for an open and informal association of like-minded organizations to promote the value
of using the Internet protocol for the networking of smart objects, says Harald Hoenninger, VP corporate
research at Bosch (www.bosch.us). “Standards for embedded IP will foster an open-systems approach
and achieve high interoperability levels, which are crucial,” he says. “As members of the IPSO Alliance, we
plan to take a role in the existing and evolving business ecosystems of embedded IT.”
This connectivity between physical objects across so many facets represents a quantum leap in
the way technology will be applied, says Mulligan. “It also explains why so many essential technology
companies are joining in our efforts,” he adds. “The numerous areas of life and platforms that will be
impacted are reflected in the caliber of companies partnering with us in these early stages. We expect to
see more well-known organizations joining with us in the months ahead.”
The introduction of IP sensors and smart objects marries IT systems with HVAC, energy,
fire, security and lighting systems, notes Joseph Noworatzky, vice president of engineering
for Johnson Controls (www.johnsoncontrols.com). “This convergence of systems creates new
synergies and applications for our customers not feasible across independent networks,” he says.
IPSO ALLIANCE
8
7/16/09 9:47 AM
Industrial Networking
Q3 • 2009
FDI Effort Inches
Toward Solution
The Field Device Integration (FDI)
Project Team, a cooperative effort among
process control suppliers and members
of the Electronic Device Description
Language (EDDL) Cooperation Team
(ECT), has performed a complete inventory
of use case analysis and designed a draft
architecture concept and draft functional
specifications in its effort to develop a
common FDI solution.
The architecture is a client/server
structure based on OPC Unified
Architecture (OPC UA) technologies. The
field device integration is realized by a
“device package” provided by the device
supplier containing EDDL components
and an optional programmed component
for programmed user interfaces. This is
designed to allow complete flexibility to
develop customized user interfaces.
The current phase of the project includes
development of the detail specifications
followed by validation of the specifications
by each of the member organizations.
Details of the exact FDI architecture and
associated device interface will be unveiled
with the release of the final functional
specification, currently planned for the
summer of 2010.
Fieldbus Foundation, FDT Group,
HART Communication Foundation,
OPC Foundation and Profibus Nutzerorganisation comprise the ECT.
capital projects to upgrading their installed
bases of equipment and keeping their
operational expenses as low as possible,
says Allen Avery, principal author of the
study. “Though the down economy will
have a dampening effect over the short
term, the need for toxic gas detectors to
9
protect plant personnel and communities
still remains,” he says. Regionally, suppliers
can expect to see the largest growth in the
Middle East, due to its high concentration
of oil and gas activities, and in Asia, where
heavy investment in plant construction
continues in core sectors.
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according to an ARC Advisory Group (www.
arcweb.com) study. The market was $689
million in 2008 and is forecasted to be $823
million in 2013, the report says.
After brisk growth earlier in the decade,
the market will take a brief respite as
companies shift their emphasis from large
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IN09Q3_08_09_Packets.indd 9
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7/16/09 9:47 AM
10
Industrial Networking
BANDWIDTH
bandwidth
Q3 • 2009
Powering field devices such as sensors
or controllers has been one of the interesting
puzzles posed to plant engineers and network
developers. And then, along came Power over
Ethernet (PoE).
While standardization as IEEE 802.3af helped
to drive acceptance and create interoperability,
the non-standard proprietary innovations
have continued to push it to its full potential,
Interoperability, as
with all technology,
is a concern for
PoE, especially
with proprietary
midspans that
support 1000Base-T
connections, which
aren’t compliant
with the IEEE
standards.
Mike Bacidore
Managing Editor
mbacidore@putman.net
IN09Q3_10_11_Bandwidth.indd 10
service, or power level, it supports, explains
Art Felgate, product manager, Transition
Networks (www.transition.com). “A PSE can
support only Class 1 and Class 2 in Mode A, for
example, and still be compliant with the IEEE
802.3af standard,” he explains. Class 1 requires
at least 4 W of power, while Class 2 requires 7
W. “If an attached PD required greater power
than Class 2, this solution wouldn’t work, even
Power to the Field Devices, Right On
whether industrial applications need it or not.
PoE is being used mostly in robotics and some
machine applications where routing any cable is
a problem and in vibration-prone applications
in machines, says Doug Erlemann, business
development manager-cameras for Baumer
Group (www.baumergroup.com). “One less
cable is worth the slightly higher cost of the PoE
system,” he says.
While most recognize the technology, PoE
is still rarely put to good use in the industrial
space, says Eric Juillerat, president and CEO of
Raven Technology Group (www.raventechllc.
com). “Ethernet has been fully accepted as
a networking bus, but it remains clouded by
decades of antiquated, in-place instrumentation
and proprietary manufacturer buses,
despite the massive availability of Ethernet
infrastructure solutions.”
IEEE 802.3af defines the power sourcing
equipment (PSE) and the powered device
(PD) that are used. A PSE is a separate device
typically installed in the wiring closet near the
Ethernet switch or hub, explains Gerard Nadeau,
PoE consortium manager at the University of
New Hampshire’s InterOperability Lab (www.
iol.unh.edu) in Durham, N.H. The PSE inserts
dc voltage onto the twisted-pair cable and can
be either an endpoint or a midspan device. An
endpoint PSE is one that contains both the data
communication capabilities and the powerdelivery mechanism. A midspan only contains
the power delivery mechanism and is inserted
in the network between the legacy, non-PoEcapable Ethernet switch and the PD, explains
Nadeau. The midspan provides the ability to
add PoE to the network without replacing the
existing infrastructure.
The PSE chooses which mode and class of
though both the PSE and PD in this case are IEEE
802.3af-compliant,” adds Felgate.
Classification of PDs should improve, adds
Felgate. “Currently, many PDs simply indicate
Class 0 compliance—full power, up to 13 W—
whether or not they actually draw that much
current,” he says. “Many PSEs can make intelligent
decisions about managing their pool of power, if
they have more accurate PD power information.
By providing a more accurate power signature
during the PoE classification stage, PDs can
contribute to more efficient use of network
resources, especially power supplies.”
Daisy-chaining is allowed by PoE, explains
Daniel Feldman, PoE/PoE+ subcommittee
technical chair of the Ethernet Alliance (www.
ethernetalliance.org) and director of marketing
for Microsemi (www.microsemi.com). “One
could build a system that receives and then
forwards power to another device, which
receives power and forwards power and so on,”
he says. “Practically speaking, one could daisychain four devices, extending the range of an
Ethernet cable up to 1,200 ft—four devices with
300 ft of cable each.”
EtherCat uses only midspan power sources
connected via Cat. 5 cable directly to the power
over EtherCat device, explains Joey Stubbs,
PE, PMP, North American representative,
EtherCat Technology Group (www.ethercat.
org). “These devices have only one connector,
which prevents the cascading or daisy-chaining
of additional devices to the network, so as
not to exceed the 802.3af current and power
limitations,” he says.
Midspan devices can be used to overcome
switch limitations, including non-support of
PoE or non-support of the maximum power
requirement of the end device, explains Paul
7/16/09 9:49 AM
Industrial Networking
bandwidth
Brooks, business development manager,
networks portfolio, Rockwell Automation
(www.rockwellautomation.com). “Users
should consider the function midspan
devices perform and understand they
aren’t required to be located near the
switch,” he says.
As some manufacturers deviate
from IEEE standards and seek new ways
to raise the limits of power delivered
over Ethernet, caution and application
ultimately will set the bar.
Interoperability, as with all technology,
is a concern for PoE, especially with
proprietary midspans that support
1000Base-T connections, which aren’t
compliant with the IEEE standards.
Some vendors are making proprietary
midspans that support 1000Base-T, but
since the designs aren’t standardized, this
could lead to the kinds of interoperability
problems that Ethernet solved long ago,
explains Nadeau.
“Because they aren’t standardscompliant, there’s a risk they won’t work
with equipment designed to meet the
forthcoming POE+ standard,” says Felgate.
Relying on IEEE 802.3 standards is
advantageous and ensures that PoE devices
are not vendor-specific, says Stubbs. “It
prevents a user from being locked into
proprietary, expensive solutions from a single
vendor,” he explains.
Nadeau agrees that the IEEE standard
provides a greater potential for
interoperability between vendors but notes
that peace of mind creates limitations. “The
disadvantages of being IEEE-compliant are
that you might not be able to squeeze all
the power out of the system and that you’re
only allowed to power on one pair set at
a time,” says Nadeau. “Proprietary systems
tend to push the limit and could power
multiple pair sets at one time.” However,
this could cause interoperability problems
and potential safety issues, he warns.
Due to the current large installed base
of IEEE 802.3af solutions, manufacturers
have an incentive to maintain compliance,
notes Felgate. “The disadvantage of relying
only on the standard is this may stifle
adoption of some of the more interesting
variations and uses of PoE,” he argues. “If
IN09Q3_10_11_Bandwidth.indd 11
Q3 • 2009
an organization has a compelling need or
requirement to deviate from the standards,
it should be fully aware of any risks that
might entail.” Gigabit, for example, was
left off of the scope for IEEE 802.3af-2003
for midspans, says Feldman. “IEEE 802.3atdraft4.2 addresses this issue,” he says. “If
the specific midspan you have in mind
11
meets IEEE 802.3at-draft4.2 requirements,
you should have no issues.”
As long as devices comply with the IEEE
802.3 standards, no problems should arise,
adds Juillerat. “In mixed environments,
the devices might need to be backwardcompatible or support mixed media or
port configurations,” he concludes.
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7/16/09 9:49 AM
12
Industrial Networking
e va lu at e
Q3 • 2009
By Dan Hebert, PE,
Senior Technical Editor
Wireless communication in industrial facilities has moved
decisively to become a practical solution. Practicality for industry means
saving money without taking undue chances, and wireless has advanced to
the point where it delivers concrete benefits with manageable risk.
The most obvious cost savings for wireless are delivered in installation,
especially for projects in existing plants. It takes lots of money and time to
dig trenches, lay conduit and pull wires. Even for above-ground installations,
the costs of conduit and wiring often are substantial.
Savings over and above lower installation costs are realized during
operations because of reduced maintenance costs and greater flexibility.
Wireless is cheaper to maintain because there are no wires or cables that can
be damaged. Wire and cable damage can occur through accidents such as
lightning strikes, contact with moving in-plant equipment and inadvertent
cutting during unrelated construction activities.
IN09Q3_12_15_CoverStory.indd 12
7/16/09 9:52 AM
Industrial Networking
Q3 • 2009
Cheaper to Install
In most instances, it’s cheaper to install a wireless system than its
wired counterpart. “We were hired by a major steel producer in the
midwestern U.S. to replace the DCS controls on four large boilers that
supplied steam to its steelmaking process,” says Timothy Stout, PE,
manager process systems for system integrator Matrix Technologies
(www.matrixti.com) in Maumee, Ohio. “Wireless saved money
because it replaced very long conduit and cable runs of up to 2
miles. This saved miles of conduit and wire, which equates to several
hundred thousand dollars in installation costs.”
Another long-distance application that resulted in substantial
savings is detailed by Michel Dubé, automation coordinator at
the Montreal facility of Para-Chem (www.parachem.com), a
manufacturer of coating, emulsion polymers and adhesives. “We
implemented remote monitoring with security cameras via a Wi-Fi
wireless system. The monitored site is 1.2 km away from our security
office, so we saved an estimated $200,000 Canadian on fiberoptic
cables and installation,” relates Dubé.
Another remote application shows the savings realized with
wireless. In this case, at Givaudan’s facility in Pedro Escobedo, Mexico,
an Emerson Process Management DeltaV control system is being
implemented in two areas separated by several miles of rugged
terrain. “A Wi-Fi bridge will connect the two areas into one larger
control system, saving the customer the cost of trenching and laying
a fiberoptic cable between the two sites or having to construct two
control rooms,” explains Neil Peterson, services manager for Smart
Wireless at Emerson (www.emersonsmartwireless.com). Givaudan
(www.givaudan.com) is a company in the fragrance and flavor industry.
The company is expanding a control system to manage three new
reactors used to manufacture base products for fragrances. These
reactors will be operated and controlled over a redundant wireless
communication link from a new remote control room separated from
the existing control room by 500 m.
IN09Q3_12_15_CoverStory.indd 13
6 + 2 = Wireless
SCHNEIDER ELECTRIC
Normal wear and tear of wire and cables is most prevalent
with connected components that move, such as those mounted
on cranes, material-handling equipment and robot arms. Wiring
and cabling to both moving and stationary components also can
suffer wear and tear through corrosion, insulation breakdown and
degradation due to temperature changes.
Another key advantage of wireless is flexibility. Once a wireless
network is installed, the cost of adding another device is very low.
Need an extra I/O point 2,000 ft from the control room? No problem
with wireless, but very expensive with a wired system.
Wireless saves costs during installation and throughout the
operational life of the control and monitoring system, but these
savings are accompanied by the risk of implementing what for
many is a new technology. Many users get around these risks by
limiting the scope of the wireless system in terms of bandwidth,
criticality and other parameters.
13
Figure 1: A wireless Ethernet system links six controllers and two
control rooms at this wastewater treatment plant in Finland.
Wireless also can save money on a smaller scale. “We have used
wireless to connect portable and stationary label printers,” notes
Harry Pettit, manager of systems and infrastructure engineering
at Pepperidge Farm (www.pepperidgefarm.com), headquartered
in Norwalk, Conn.
“Wireless provides flexibility in equipment location that you don’t
get with hardwired, and we also estimate installation savings at $1,500
per printer,” adds Pettit.
Wireless not only saves money on installation labor, it can cut
design costs. “With wireless, engineers don’t need to sort through
rolls of schematic diagrams, installation and termination details
and the drawings for the fabrication and layout of the cable
tray, conduit, junction boxes and interface panels,” observes Joe
Bingham, president and CEO of system integrator AES Global (www.
aesglobal.com), Anaheim, Calif.
OperationAL EASE
The central wastewater treatment plant of Lapuan Jätevesi Oy, in
Lapua, Finland, treats household and industrial wastewater (Figure
1). The original automation system from 1992 was replaced in 2008
with new controllers, SCADA software and a wireless communication
network in a project with Schneider Electric and system integrator
Seinäjoen Teollisuussähkö Ky.
About 2,000 process variables are transmitted over the wireless
network, and the network also is used for programming and
maintenance purposes. A number of locations had to be linked as the
control system has six controllers located in different buildings along
with two control rooms.
7/16/09 9:53 AM
14
Industrial Networking
e va lu at e
Q3 • 2009
From the user point of view, the main advantage was the cost and
time savings for the installation as there was no need to dig trenches
or modify existing cable paths.
From Seinäjoen’s point of view, the wireless RadioLinx network was
the easiest part of the implementation. It didn’t have any problems, as the
radios are very easy to configure and mounting recommendations given
by radio supplier ProSoft Technology were very clear, says Seinäjoen’s.
Schneider Electric made some tests and then explained how to
implement the wireless network in the field.
MAINTENANCE REDUCTIONS
Wireless technology can help manufacturers reduce the skill set required
for maintenance tasks. “Most maintenance issues are mechanical
problems,” observes Cliff Whitehead, manager of strategic applications at
Rockwell Automation (www.rockwellautomation.com).
“Rather than alert a highly skilled, high-cost controls engineer for every
fault, manufacturers can alert locally based mechanical technicians,”
explains Whitehead. “These mechanical technicians are better- equipped
to solve the majority of problems but sometimes need the support of
controls engineers. To accomplish this, manufacturers can make a wireless
cellular modem part of the mechanical toolbox to create a connection
that is locally manned by mechanical technicians and remotely manned
by centralized controls engineers.”
Wired systems not only experience wiring and cable failures, but also
other problems linked to hardwiring. “Wired instrumentation tends
to get damaged through power spikes in the system that can burn out
analog input channels,” observes AES Global’s Bingham. “These defects
are difficult to troubleshoot, but burnt analog input channels are a thing
of the past with wireless instruments, and the loss of the instrument is
easily detected through the loss of communications.”
I, Robot; You, Wireless
PHOENIX CONTACT
Wireless is a natural fit in applications
such as robot arms where I/O must be
connected to moving parts. Motion Controls
Robotics (www.motioncontrolsrobotics.
IN09Q3_12_15_CoverStory.indd 14
com) provides full-service robotic solutions
to customers worldwide from its 57,000 ft2
facility in Fremont, Ohio.
One of its customers, a manufacturer
and marketer of paper and plastic
disposable packaging for the food service
industry, needed a robotic system to
palletize cases of product. The system
consists of five robots, each mounted on a
50-ft rail system. At the end of the robotic
arm is a tool with eight double-solenoid
valves and one photo eye sensor, requiring
16 outputs and one input.
To provide adequate wired I/O, the
system would require expensive high-flex
cable the length of the rail system along
with soldering three separate connection
points with approximately 20 wires
per connection. Working with Phoenix
Contact (www.phoenixcon.com), Motion
Controls Robotics found a solution that
instead uses Bluetooth wireless.
The PLC that controls the overall
system connects via EtherNet/IP cable to
a bus coupler. The coupler connects to
five Bluetooth wireless I/O base stations
A wireless bridge connects I/O at the
end of this robot arm to a central
controller. The robot is used to
palletize boxes.
located nearby. Each of the base stations
then connects wirelessly to two Bluetooth
wireless I/O devices mounted on each of the
robotic arms, located 80-120 ft away from
the base stations. Each of the I/O devices
has eight inputs and eight outputs.
The bus coupler, the five base stations
and the 10 Bluetooth-enabled I/O modules
all are housed in IP65/IP67 blocks for direct
machine mounting. Unlike Wi-Fi, which
also uses the 2.4 GHz spectrum, Bluetooth
uses the frequency-hopping method of
spread-spectrum wireless that results in
higher energy per bit and punches through
any noise floor present. These hops occur
1,600 times per second, so when a packet is
lost to interference, the next transmission
is sent 625 μsec later.
Eric Hohman, PLC programming and
systems design engineer for Motion
Controls Robotics, says wireless I/O
eliminated about 20 hours of wiring and
soldering per robot.
“Wireless eliminated two separate cables
in two different areas that are continually
flexing,” observes J.P. Yeager, electrical
designer for Motion Controls Robotics.
“The lifespan of these types of cables
can be several months to several years,
but eventually they fail and require timeconsuming replacement.”
7/16/09 9:56 AM
INDUSTRIAL NETWORKING
Q3 • 2009
“WIRELESS HAS ITS PLACE WHEN
YOU CAN GET BY WITH GAPS
OF MISSING DATA OR WHEN YOU HAVE
DIFFICULTIES GETTING WIRING
TO SENSORS OR I/O.”
Not only does wireless save money during ongoing operations,
it also can be safer. “Wireless improves safety by simplifying
monitoring, modification and upgrades,” says Robert Konermann,
product marketing manager for automation and safety at
Schneider Electric (www.schneider-electric.us). “This can
be significant with electrical panels containing high-voltage
equipment, particularly when water or other hazardous conditions
are present. Because of the wireless network, workers don’t need
to be in physical contact with the panel or open the panel doors
to expose the wiring, components or live equipment.” Long-term
savings are abundant due to the flexibility of wireless, which makes it easy
to add, replace or modify components, adds Konermann.
WHAT’S HOLDING WIRELESS BACK?
Wireless works in the right application but, like any technology, it has
limitations. “Wireless has its place when you can get by with gaps of
missing data or when you have difficulties in getting wiring to sensors
or I/O,” says Gary Crenshaw, electrical engineer at Beam Global Spirits
and Wine (www.beamglobal.com) in Clermont, Ky. “But I don’t see
wireless replacing all control system hardwiring. Cell phones are some
of the best wireless devices we have, but they are not 100% reliable.
They are dependable enough to be very useful, but they can’t be
counted on in an emergency.”
WIRELESS ADVANTAGES
1. Cheaper installation
2. No wear and tear on cables
3. Easier to modify
4. Better for mobile equipment applications
WIRELESS CHALLENGES & ISSUES
1. Slow data transmission rates
2. Dropped data packets
3. Lack of experience among end users
4. Conflicting standards
IN09Q3_12_15_CoverStory.indd 15
15
WIRELESS WELLS
Wireless becomes almost a necessity when long distances
need to be traversed to reach a mobile location like an oil
drilling rig. “We had a project that required connection of
a device used to monitor the amount of gas produced by
a drilling operation,” says Lee Hilpert, president of system
integrator HilTech (www.hiltecheng.com) in Tomball, Texas.
“The sensors and instrumentation are several hundred
feet from the area where the data is needed. In addition, the
drilling rig moves about every 45 days. Without wireless, it
would be necessary to dig a trench, bury conduit to run a
communication cable, pull and terminate the communication
cable and hope nobody compromises the cable during the
drilling process. With wireless, you set it up and turn it on,
and installation takes less than a man-hour.” With a wired
installation, you’d then have to disconnect, pull wire, remove
the conduit and remediate the trench.
The two RF modems installed at the oil rig and at the
system computer have some limitations. “The transfer rate
is low compared to a wire or fiberoptic system, but data
exchange requirements also are low,” observes Hilpert.
He says the savings are significant. “The wireless link costs
less than $1,000,” says Hilpert. “The Digi 900 MHz modems
are about $300 each and are essentially plug and play.
Compare this to hardwiring where, at best, it’s going to take
two men at least a day. ”
THEN, THERE’S THOSE STANDARDS
The lack of standards for wireless has delayed implementation, but this
is improving. “Wireless standards such as IEEE 802.11 will improve user
confidence because its spread-spectrum modulation techniques are
less susceptible to interference,” argues AES Global’s Bingham. “The ISA
100 wireless standard helps make implementation easy due to wide
acceptance in the instrumentation and automation industries.”
Vendors and industry organizations are jumping on the standards
bandwagon. “At one time, we expected to create a Profibus process
wireless standard,” comments Carl Henning, deputy director for
Profibus and Profinet in North America (www.us.profibus.com).
“But, with the release of WirelessHART, we realized that was no longer
necessary. Instead we formed a cooperative team with the Fieldbus
Foundation and the HART Communication Foundation to simplify
access to WirelessHART from our respective technologies,” adds Henning.
Standards already promote use in some applications. “ISA
100 compliance was a key factor in selecting Honeywell for our
project,” comments Para-Chem’s Dubé. “The standard will allow us
to add wireless devices from many different suppliers in the future,
and these additions will show much higher payback because the
wireless infrastructure is already in place.”
7/16/09 9:57 AM
16
Industrial Networking
im p l e m e n t
Q3 • 2009
Frustrating Obstacles and Unexpected Mysteries of a Wireless
Network Project Aren’t Covered in the Manual
Wireless: The Real World
By Alice McWilliams, PE, Chevron Phillips
The application of new technologies seldom goes as
planned and can be an outright adventure. But the potential for
significant cost savings can make overcoming the hazards and pitfalls
well worth the journey.
That was the case at our plastics plant in Pasadena, Texas, where
we needed to overcome obstacles and create a wireless system to
monitor certain data readings.
Initially, the impetus for the project involved the need to obtain
two readings, but things escalated quickly. The equipment was
installed in August 2007. Design for the installation had started
earlier, in February.
the Wireless Opportunity
We use a 40-ft-tall API tank when we unload a barge. Each time, the
operator would climb the tank to record temperature at the vent
and vent valve position after the tank’s condenser unit. The plant
wanted to automate the recording of measurements to record the
vent temperature and vent valve position to provide improved
CHEVRON PHILLIPS
Figure 1: TO THE TOP OF THE TANK
Eliminating the time-consuming, repeated trek to the top of the
tank with a wired measurement solution would have required a
40-ft-tall scaffold to run the conduit and cable.
IN09Q3_16_19_featr2.indd 16
documentation for our environmental records and improve operator
efficiency by eliminating the time-consuming, lengthy, repeated trek
to the top of the tank (Figure 1).
Because the process variables we wanted to measure were at the very
top of this tank, it would have required a long cable and conduit run up
the side of the tank. It would have required a 40-ft-tall scaffold to run
the conduit and cable. The costs to obtain just two new readings didn’t
seem justified compared to a traditional hardwired method.
“We began to look at a wired solution,” says John Scott, senior
account manager from the Rosemount division at Emerson Process
Management (www.emersonprocess.com), “but we came up with a
65% installation savings by going wireless. One of the bigger costs for
a wired solution would have been the scaffolding.”
Wireless obviously was the best choice. We looked at several
wireless network solutions, but determined that Emerson was a good
choice for this plant. Regular-style wired Rosemount transmitters
already were used at this unit. Training on the handheld was up-todate. This meant that training only needed to cover troubleshooting
changes due to the wireless hardware and setup. This would minimize
our training costs, as well.
Wireless Network Design
We began to seriously explore implementing a wireless solution
to this problem. One concern was how to provide valve position.
Emerson didn’t offer any direct valve-positioning transmitters except
as an add-on to the digital valve positioner. The controller for tank
pressure was a local pneumatic controller with a pneumatic valve
positioner. I eventually realized that I could use a pressure transmitter
on the controller output and provide an implied valve position.
Designing a wireless network, to my interpretation, meant that cable
runs were kept to a minimum, reducing both installation and material
costs. It seemed, therefore, that the best location for the wireless
gateway would naturally be on top of the rack room (Figure 2). I could
easily interface with the old Provox DCS equipment via the intelligent
device interface module set to accept Modbus and run only three short
cables—Modbus, Ethernet and power—to the roof.
This older version of the wireless network required that the
distance to the gateway be less than 500 ft. The temperature and
valve-position-measurement points were 600 ft away from the rack
room. Additional transmitters between the API tank and the rack
7/16/09 10:15 AM
Industrial Networking
Q3 • 2009
Our radio group was very concerned about
a network that would run at the same
frequency as the plant radio system.
Transmitter Update-Time Decisions
Wireless transmitters don’t provide data at a very fast update
rate. Emerson generally recommends update times around a
minute. Pressure is a fast-changing variable, and I was particularly
concerned about the slow update rate for the two pressure
transmitters on the unloading line. What if, at a 1-min update rate,
we totally missed recording the event that signaled the pressure
excursions on the unloading line?
In the end, I picked 15-sec update rates for all the transmitters except
the barge unloading pressure. I found out at installation that, although
the recommended lower limit was 15 sec, the system actually could
perform at much faster rates. I selected a 3-sec update rate for the
barge unloading line pressure. The downside to changing to a faster
update rate was sacrificing some battery life and gateway capability.
Transmitter Variables
These days you can pick and choose what you feel is important
IN09Q3_16_19_featr2.indd 17
figure 2: UP ON THE ROOF
CHEVRON PHILLIPS
room were needed to act as repeaters for the API tank data. These
additional wireless applications between the API tank and the rack
room would improve both distance and stability needs. Mesh wireless
networks also become more stable as the number of nodes to the
network increases. Fortunately, it was easy to find more readings that
the plant wanted. The production engineers for our unit also were
excited about trying a wireless network. Two additional measurement
applications, the bearing temperatures for two pumps and the barge
unloading line pressure, fell into our laps (Figure 3).
One of the pumps on a tank closer to the rack room had
experienced bearing failure earlier that year, and caused a
hydrocarbon leak into the electrical housing. Monitoring the
pump bearing temperature would improve reliability and safety
in this operation.
Also, our barge unloading line was experiencing pressure
excursions in excess of what we would like. It wasn’t easy for the
production engineer to tie the higher pressures with specific events
during the unloading cycle. Most of the unloading valves were handoperated, and the barge unloading information also was isolated to
the dock area. The recorded pressure indication could help determine
the point in the cycle when the high pressure occurred, so we could
develop better procedures for preventing recurrence. Both of these
applications were a great opportunity to bring information that
would provide improved plant operation to the DCS. In the end, we
planned to develop a wireless network consisting of five transmitters:
tank vent temperature, vent valve position, two pump-bearing
temperatures and barge unloading line pressure.
17
The gateway on the rack-room roof was difficult to access,
which was discovered when the first gateway developed mold
on an electrical card before the network was even launched in
August 2007.
information from your transmitters and bring this data into the DCS.
I heard and read a lot about battery life and battery voltage from
Emerson’s experts and literature. I decided that, besides the main
transmitter variables, I also would bring in the battery voltage as an
additional variable for each transmitter. This turned out to be a good
decision. Now I regularly review the battery voltages, and we created
an alarm to alert the operator when the voltage dropped too low.
What About Radio Interference?
For the installation of a wireless network, another hurdle needed to
be cleared. Our plant radios use the same 900 MHz frequency range
as the network. The radios provide critical communication for our
operators, especially if an abnormal situation should develop in the
plant. Our radio group was very concerned about a network that
would run at the same frequency as the plant radio system.
We held two separate in-plant trials using Emerson sales-demo
units. During the second trial, the radio group brought its frequency
analyzer. It showed no interference. However, they still were not
completely comfortable, and wanted us to wait until the 2.4 GHz
wireless transmitter network was available. To put their minds at ease,
Emerson’s Scott explained five key aspects employed by the network
security, including protection/encryption, authentication, verification,
key management and anti-jamming. That satisfied their concerns.
7/16/09 10:16 AM
18
Industrial Networking
Q3 • 2009
Mind the Details
By July 2007, I was reviewing the installation by our on-site
construction team. At this point, I realized that none of the
transmitters had batteries installed. Apparently, the batteries were
delivered separately and without a specific line on the purchase
order (PO). The receiving department didn’t have the means to
handle a delivery that didn’t match to the PO. All the new batteries
were lost and never located. The planned imminent installation by
the Emerson team was delayed several weeks while the batteries
were reordered and delivered.
Gateway Troubles
Since the gateway and antenna were married together, I thought
putting the gateway on top of the rack room to receive signals
from all different directions within the plant would be a good idea.
Unfortunately, the roof was difficult to access. We discovered how
inconvenient a location this was when the first gateway developed
mold on an electrical card before the network was even launched
in August 2007. Emerson replaced the gateway under warranty.
The second gateway quit in November 2007, a little more than two
months after it was installed.
Then, one day all the points started drawing straight lines. I had
five or six irons in the fire that day. So, rather than call Emerson’s
tech support, I cycled power in the hope of resetting it. Due to the
lack of any luck at all, that action vaporized all stored data on what
had gone wrong with the gateway. The failure of this gateway, after
post-mortem analysis, again pointed to the radio card. Emerson again
replaced the gateway under warranty and lent its demo unit to us
until the warranty replacement gateway arrived.
When the third gateway came, it included a remote antenna.
CHEVRON PHILLIPS
figure 3: MESH NETWORK
Additional transmitters were needed to act as repeaters. Mesh
wireless networks also become more stable as the number of
nodes to the network increases.
IN09Q3_16_19_featr2.indd 18
implement
This was a feature I had wanted from the start, but it only recently
had become available. Getting the gateway down from the roof
and adding the antenna made a huge difference in troubleshooting
accessibility. Finally, the wireless gateway with remote antenna was
installed and operational. It seemed things were looking up.
Wireless Mysteries
The temperature transmitter on the very top of the API tank—the
sought-after measurement that started this grand adventure—was
the first one to give me trouble. One lovely day in December 2007, the
outside temperature was 70 °F. The next day the temperature plummeted
I decided that I also would bring in
the battery voltage as an additional
variable for each transmitter. This
turned out to be a good decision.
to 35 °F. This transmitter provides the condenser temperature reading
that was the cornerstone of the whole wireless network project.
Examining trends of the battery voltage showed 6.84 Vdc on Dec. 15 and
5.56 Vdc on Dec. 16. Somewhere around 5.5 Vdc is the point at which
the transmitter stops functioning. I was very surprised to have a battery
failure after only four months of operation. From what I had discerned
from the vendor literature, I expected these batteries to last for years. I
hadn’t expected to need spares so soon.
Emerson brought a replacement battery, and soon we were back
in operation, but I continued to be puzzled by the battery failure.
Obviously, these batteries developed lower voltages in the colder
weather. I tried without success to procure some sort of graph or
formulas to determine battery life. Battery life apparently was meant
to remain a mystery to all users.
Mysteries continued with a new slant. My important API tank
condenser temperature transmitter suddenly stopped transmitting on
March 6, 2008. Sixteen hours later, before I could even determine that
it had gone nonfunctional, the transmitter resumed sending data. Did
something get in the way of the radio signal and break the path?
The condenser transmitter had two communication paths to the
gateway: one directly to the gateway (600 ft) and another relayed through
the valve-position pressure transmitter (5 ft away). This transmitter was
on top of a 40-ft tank, and the pressure transmitter that it communicated
with most reliably continued transmission of its data throughout this
episode. Battery voltage was not an issue. The voltage when the device
quit communicating was 7.08 Vdc. Emerson performed an on-site
mapping of the wireless network system operation through the 1420
Gateway. However, this offered no clues to what caused this mysterious
signal loss. This same event occurred on this condenser temperature
transmitter later in 2008. This time, the transmitter was rebooted to start
communicating by pulling out the battery and putting it back.
7/16/09 10:16 AM
Industrial Networking
Q3 • 2009
CHEVRON PHILLIPS
Figure 4: STICKY SITUATION
Houston’s humid weather caused water
to accumulate beneath the transmitters’
covers, which necessitated Teflon tape on
the conduit plugs to discourage outside
air exchange.
I again contacted Emerson to glean
some additional insight into why this
transmitter would lose contact with the
wireless network. They offered to repeat the
system mapping that had been done earlier.
I declined the offer since it required taking
the whole network down for an hour or
so, and the process had yielded nothing to
help previously. They did suggest trying the
antenna on the transmitter at a different
angle. We implemented this suggestion, and
the condenser temperature transmitter has
remained in communication since that date.
Trouble When Wet
The batteries, however, were not finished
plaguing me. On April 28, 2008, one of the
pump-bearing temperature-transmitter
batteries dropped to 5.37 Vdc during an
ambient temperature swing of approximately
20 °F down to 58 °F, the point at which the
transmitter failed high. This battery was
replaced after a life of about one year.
I was confused. Where were the years
of battery life that the literature talked
about? At Emerson’s conference in October
2008, I discussed battery life with any
Emerson expert who would listen. One
of these experts told me that one year
really was what might be expected with an
update time of every 15 sec. I keep looking
IN09Q3_16_19_featr2.indd 19
for that chart where I actually can calculate
battery life myself.
At one point, given our concern about
losing signals and batteries, we removed
the transmitters’ covers and found some of
them had condensation on the batteries. The
first thought was: “Wow. This is the source
of our problems.” The recommendation was
to put Teflon tape on the conduit plugs to
discourage any outside air exchange with
Houston’s humid weather (Figure 4). Little
details often make the difference. However,
it’s difficult to prove whether this made a
big difference in our battery life because this
pump bearing temperature transmitter is
not done with me yet. It failed again on May
18 and again a month after that. It turns out
this was a good transmitter gone bad—a
transmitter that ate batteries. Emerson
provided a replacement under warranty, and
there have been no failures since.
19
Adventure Lessons Learned
With all of these lessons came a lot of
valuable experience, not the least of
which was the skill set we developed
troubleshooting wireless. Plus, we added
the temperature transmitter ourselves,
without Rosemount, to prove the system
is easy to maintain and grow. We also
got a lot of valuable process information
at a much lower cost due to the 65%
installation savings. The barge-unloading
pressure did provide the information
needed to determine improved operation
practices. And, when Hurricane Ike hit in
September 2008, the network kept running
without a hitch right through all that
extreme wind and rain.
Alice McWilliams, PE, is senior instrument
and controls engineer at Chevron Phillips
(www.cpchem.com) in Pasadena, Texas.
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7/16/09 10:17 AM
20
Industrial Networking
research
Q3 • 2009
Routers and Switches Continue to Manage and Direct DatA on
the Network Information Highway
The Once and Future Network Traffic Cops
As more industrial devices with built-in Ethernet
capabilities are introduced, networks will become more complex and
crowded with signal traffic. “This will increase the need for Ethernet
switches and routers with advanced functionality that can limit
collisions, control bandwidth and create virtual local area networks
(VLANs),” says Chris Vitale, senior product manager with Turck’s
network and interface division (www.turck.com).
“An advantage of today’s LAN switches over earlier LAN hubs
and repeaters is the presence of microprocessors in the switch
to selectively direct communications from one remote device to
another,” explains Jim McConahay, PE, senior field applications
engineer for Moore Industries International (www.miinet.com).
“With switch technology improving, we will see a greater emphasis
on the built-in intelligence, which will allow someone who is welltrained in Ethernet to make dramatic improvements to their device
communications,” says Erik Syme, technical support manager at
ProSoft Technology (www.prosoft-technology.com).
“Ethernet routers and switches will not go the way of hubs and
repeaters today because they provide industrial engineers with two
valuable items, control and flexibility, whereas hubs and repeaters
only provided connectivity,” explains Bruce Hofmann, director of
marketing, Weidmüller North America (www.weidmuller.com).
SNMP CONVERSION
Noise Immune Switch
Bradcommunications 200 Series DirectLink industrial Ethernet unmanaged
switches are equipped with five-,
eight- or nine-port switches and are
plug and play. Other features include
auto-sensing, auto-polarity and autocrossover. Each is DIN-rail- or panel-mount and equipped with
redundant, dual dc power inputs. The 300 Series managed switches
are equipped with IGMP snooping, VLAN and QoS for prioritization
and support redundant ring network technology and advanced
network management. Direct-Link SNMP Management Suite converts
SNMP messages into OPC tags that can be incorporated into and
portrayed by HMI OPC client software.
Molex; 800/786-6539; www.molex.com
EKI-4654R is an IEC 61850-3-compliant
managed Ethernet switch for grid
automation applications. IEC 61850-3
certification ensures environmental
and EMI immunity. The switch features
24 10/100BaseT Ethernet ports and two 1000BaseTSFP slots. It has
a wide range of redundant power inputs, allowing connection to
two separate power supplies and guaranteeing operation in the
event one source goes off-line. The switch supports X-Ring, standard
Spanning Tree and Rapid Spanning Tree protocols.
Advantech Industrial Automation Group; 800/205-7940;
www.advantech.com/ea
WORKGROUP SWITCH
Mach10019-in. rack-mount switches operate 0-50 °C without
fans. The switches include two Gigabit RJ45/SFP combo ports
and are offered with either eight or 24 permanently installed 100
Mbps ports or as a modular device with eight ports and slots
for two other eight-port media modules. These modules, which
are designed for 100 BaseTX, 100
BaseSFP or 100 BaseFX (multimode
and single-mode), can be changed
during operation by means of a hotswap function.
Hirschmann; 717/217-2200;
www.hirschmann-usa.com
IN09Q3_20_23_Research.indd 20
Smart Switches
Stride line has been expanded to include industrial-grade unmanaged
Ethernet switches and media converters with aluminum housings.
Designed for wide-temperature (-40 to 85 °C) applications,
these true plug-and-play devices automatically determine and
remember devices connected to each port and only route
messages through the appropriate ports, increasing speed and
bandwidth. Even under heavy
I/O and data exchange, Stride
switches and the Ethernet
control network maintain more
consistent cycle times.
AutomationDirect; 770/889-2858;
www.automationdirect.com/
ethernet
7/16/09 11:24 AM
Industrial Networking
Q3 • 2009
21
Messaging Module
POE SWITCH
Message Manager ILX56-MM
module is a multi-system data
transfer engine that resides in a single
slot of a ControlLogix chassis. The
module enables PLC-to-PLC data
transfer without requiring message
programming or ladder logic. The module is configured using a builtin graphical Web-based configuration tool with user prompts. Data
transfers can be set up by users at one location for up to 16 different
Rockwell Automation and Siemens controllers.
ProSoft Technology; 661/716-5100; www.prosoft-technology.com
Simple Managed Switch
Fully managed, eight-port PoE
switch is designed to power network
devices intelligently and enable PoE
infrastructure via fiber. The ruggedized
device comes with built-in dual fiber
uplinks and is backed by a lifetime
warranty. The SISPM1040-182D-LR(T)
provides fiber connectivity and can power wireless access points.
All RJ45 ports support Auto-negotiation and AutoCross, and all
SFP ports support both 100BaseFX and 1000BaseXSFP optics. The
eight RJ45 ports w/PoE fully support the IEEE 802.3af standard,
providing a full 15.4 W to as many as eight devices.
Transition Networks; 800/526-9267; www.transition.com
Industrial Ethernet ring switch offers the performance features of a
managed switch with the simplicity of an unmanaged switch. The switch
comes preconfigured for ring redundancy, offering virtual plug-andplay performance, and it uses self-healing ring topology. The switch
provides the port mirroring, broadcast
storm protection and priority queuing of a
managed switch. In addition to offering fast
recovery time of 30 msec + 5 msec/hop, the
switch allows for real-time data transfer with
IEEE 802.3 Ethernet compliance.
Ultra Electronics; 512/434.2850;
www.ultra-nspi.com
852 series Ethernet switches offer an alarm contact, enabled via
dip switch, to signal an error condition on the switch. The power
input connector on the switch has two
dedicated alarm circuit connections that
can be wired to any warning device, such
as a PLC. Error conditions that can be
monitored include port link failure, power
supply disruption/disconnect or power
supply voltage out of specified range.
Wago; 800/din-rail; www.wago.us
ALARMING SWITCH
First FISCO Fieldbus
Entry-Level Switch
Route-Master Fieldbus System has a
new ATEX approval (FM pending) as
a redundant intrinsically safe fieldbus
system, permitting the connection of
any mix of FISCO and Entity devices.
This is the first fieldbus system approval
to offer FISCO compatibility and power redundancy. A Route-Master
system consists of up to eight trunk isolator modules in a 19-in. rack, each
connected to one or more RM100 fieldbus device couplers.
Moore Industries-Int’l; 818/894-7111; www.miinet.com
Scalance X family of industrial
Ethernet switches has been
expanded to include the simpleto-use, space-saving and affordable
Scalance XB. The entry-level
Scalance XB unmanaged industrial Ethernet switch can be used in a
line or star topology where simple plug-and-play connections and
low-cost port expansion features are required. The Scalance X family
of switches are available with up to eight 10/100 Mbps ports.
Siemens Energy & Automation; 800/241-4463;
www.sea.siemens.com
Sync Your Clocks
EL6692 EtherCat bridge terminal improves synchronization for highly
complex machines and production lines with numerous EtherCat
masters. In the most complex systems, data may have to be exchanged
between individual EtherCat systems, or the distributed clocks of
different systems may have to be synchronized. The bridge terminal
is an ideal solution as it cost-effectively
implements these tasks directly in the I/O
system. In addition to normal data exchange,
the EtherCat bridge permits distributed clock
synchronization.
Beckhoff Automation; 952/890-0000;
www.beckhoffautomation.com
IN09Q3_20_23_Research.indd 21
Multi-Port Switches
EK series of rack-mount industrial
Ethernet managed switches are
offered in 26-port and 32-port
models. These switches are industrialrated and designed to meet the
requirements of power substations
(IEC 61850/IEEE 1613), traffic control
(NEMA TS2), railway applications (EN 50121-4) and maritime use
(ABS/DNV/GL). The compact 1U rack-mount packaging fits into
standard EIA, WECO and ETSI racks 19-24 in.
Sixnet; 518/877-5173; www.sixnet.com
7/16/09 11:25 AM
22
Industrial Networking
research
Q3 • 2009
USB Hubs
Gateway to DeviceNet
Four-port and seven-port hubs
are USB 2.0-compliant, providing
480 Mbps data rate to the host,
and are backward-compatible
with USB 1.1 and 1.0 devices.
Each includes a wall-mount ac
adapter that supplies 500 mA to each attached USB peripheral. Both
hubs are housed in rugged plastic enclosures. The hubs are supported
in Windows, Linux and other USB-aware operating systems.
Sealevel Systems; 864/843.4343; www.sealevel.com
DeviceNet gateway joins gateways
in BL20 economy system. The
gateways provide a cost-effective
solution to expand fieldbus I/O
and connection of up to 32 I/O
modules, including digital and
analog, for a system that can handle 512 digital I/O points or 128
analog I/O points. A combination of digital and analog I/O on a
single node is an option.
Turck; 800/544-7769; www.turck.com
High-Throughput Radio
Versatile Switch
702-W industrial wireless Ethernet radio with IEEE 802.11n
support allows the radio to use three antennas and multiplein-multiple-out (MIMO) technology
for increased throughput, yielding
much higher data rates than devices
supporting only 802.11a/b/g. The radio
supports 802.11a/b/g compatibility for
existing wireless networks. Extended
environmental specifications allow
operation in temperatures from -40 to
70 ºC. Auto sensing 10/100BaseTX is included.
N-Tron; 251/342.2164; www.n-tron.com
Entry-level industrial-grade Magnum 6KQE Ethernet managed
edge switch is compact and environmentally sealed for physically
and environmentally constrained installations. Its modular design
supports up to 8 10/100TX
and 2 GigE Ethernet ports,
with configuration options
for TX or fiber interfaces
and optional power over
Ethernet (PoE), as well
as several integral power supply options. The switch provides
advanced networking features such as RSTP and VLANs, as well as
management interfaces.
GarrettCom; 510/438-9071; www.garrettcom.com
I/O Hub System
Standalone Ethernet hub system is part
of the X20 slice I/O series. The modular
design of the active hub allows it to be
used as a 4x or 6x hub. The smallest
version is a solution as a 2x hub for
extending Ethernet sections up to
200 m. Besides standard Ethernet, the
modular hub system can be expanded
with an X20 bus controller module with an integrated 2x hub for
Ethernet Powerlink.
B&R Industrial Automation; 770/772-0400; www.br-automation.com
it’s MANAGEable
Stratix 8000 modular managed switch
line with six to 26 ports includes
the resilient Ethernet protocol
(REP), DHCP per port and CIP sync
protocol. It uses Cisco Catalyst
switch architecture and feature set
and can be configured using RSLogix 5000 programming software. It
automatically generates Logix tags for integrated diagnostics. Switches
have a removable compact Flash card.
Rockwell Automation; 440/646-3434; www.rockwellautomation.com
Intelligent Switch
ASi Modules
Smart Managed Compact Switch (SMCS) has eight ports capable
of simultaneous Gigabit operation. SMCS is suitable for Profinet,
EtherNet/IP and standard Ethernet applications. A version with
eight twisted-pair ports and another with six twisted-pair and two
fiber ports are available. The switch’s
integrated Web server provides access
to switch functions and settings. It can
be configured using the Web browser,
simple network management protocol
(SNMP) or a serial connection.
Phoenix Contact; 800/322-3225;
www.phoenixcon.com
VBA-4E4A AS-Interface junction-box modules are 28.65 mm
high and deliver 4-in/4-out functionality to support 62 nodes
per network. All I/O is powered
directly by the AS-Interface
module, eliminating the need
for an additional power source.
Industrial dual-lock mounting
strips increase the total mounting
height to 35 mm. Removable
terminals enable programming and module change-outs, and LED
indicators help with troubleshooting.
Pepperl+Fuchs; 330/486-0001; www.pepperl-fuchs.com
IN09Q3_20_23_Research.indd 22
7/16/09 11:26 AM
Industrial Networking
Q3 • 2009
23
Secure Routers
Industrial Ethernet routers are designed
to provide networking options and
controls such as firewall protection,
remote network access, virtual mapping of
networks, virtual private networks, DHCP
server options, DNS server functionality
and network callback features. The routers
provide the tools and capacity for superior
network security such as SSH tunneling,
VPN, virtual mapping (NAT), port
forwarding, port filtering and a packetlevel inspection firewall.
Weidmüller; 800/849-9343;
www.weidmuller.com
electrical, EMI and other critical threats.
Modular rack-mount design with high optical
fiber and Gigabit port density make the
switches suited for retrofitting existing stations
or establishing networks for new substations.
Layer 3 routing is supported for better
performance on large-scale substation LANs.
Moxa Americas; 714/528-6777;
www.moxa.com
ETHERNET/IP TO PROFIBUS
Anybus X-gateway connects PC-based OPCclient applications through standard Ethernet
networks and the X-gateway to all major
fieldbus networks. The OPC connectivity
Extend the Data
LDM heavy-duty modems extend the
distances that computers, terminals and
other devices can communicate in hazardous
industrial and institutional environments.
Six models communicate over continuous
dedicated wire pair and distances to 12
miles using standard RS-232/485 protocols.
Two additional models feature fiberoptic
data links for total electrical isolation and
operation to 2 miles.
Dataforth; 520/741-1404;
www.dataforth.com
IEC 61850-3 COMPLIANT
PowerTrans IEC 61850-3 and IEEE 1613
compliant Ethernet switches protect against
IN09Q3_20_23_Research.indd 23
feature is available for 19 industrial Ethernet
to fieldbus versions of the X-gateway family
with more than 50 combinations to choose
from. It enables PC-based OPC DA client
application to access data of distributed field
devices located in a fieldbus network without
the need for a PCI fieldbus interface card.
HMS Industrial Networks; 312/829-0601;
www.anybus.com
MORE, MORE, MORE
Find more information about routers
and switches from companies including
Digi, GE Intelligent Platforms,
Lantronix, Ledco, Omron STI and
Saelig at www.IndustrialNetworking.
net/Q32009research.
7/16/09 11:26 AM
24
Industrial Networking
MULTI-PORT JUNCTION BLOCKS
M8 multi-port, IP67-rated junction
blocks have three-pin M8 connectors
(v3 style) in four-, six- and eight-port
models. They allow multiple sensors to
be wired to a single block with a single
cable run back to a controller.
Pepperl+Fuchs; 330/486-0001;
www.pepperl-fuchs.com
Phone Home
GSM/GPRS serial modem
provides global access to
machines and systems via GSM
connections. An integrated
TCP/IP stack allows the
implementation of simple control
systems into the GPRS network.
A pre-installed SIM card makes
activation quick and easy. It features two digital alarm inputs via
Combicon connector and one digital output via T-bus connector.
Phoenix Contact; 800/322-3225; www.phoenixcon.com
TC SIGNAL CONDITIONERS
8920-500-DC and 8921-1250DC signal conditioners are for
applications where single-point,
isolated thermocouple signal
conditioning is required. 8920-500DC is for Type J thermocouples
with a range of 0-500 ºC. 89211250-DC is for Type K with a range
of 0-1,250 ºC. Both use linearization and cold junction compensation
and provide three-way signal isolation.
Calex; 800/542-3355; www.calex.com
TWIST AND SHOUT
Chainflex CF Robot shielded
robot cable is designed for
applications with high levels of
torsion such as robots, rotary
tables or spindle drives. The
torsion-resistant tin-plated
copper shield sheath has been
tested through more than 3 million movements to ±270°.
Igus; 800/521-2747; www.igus.com
PRINT TAGS
PrintJet Pro ink-jet printer prints plastic markers in standard
MultiCard format. 600-dpi print quality is designed for printing
tags and markers for direct mount onto devices, cables, relays and
IN09Q3_24_25_Products.indd 24
products
Q3 • 2009
terminal blocks. Black and
color print is produced using
water-based environmentally
friendly ink. M-Print Pro
software is engineered to
operate intuitively and can
link directly to CAE/CAD
systems. The controls panel is
flush-mounted on the top of
the printer and can be rotated 180° for ease-of-use.
Weidmüller; 800/849-9343; www.weidmuller.com
Signal Conditioning
Two new signal conditioning modules are Adam-3112 and Adam3114. The Adam-3112 is an isolated ac voltage to dc voltage module,
while the Adam-3114 is an isolated ac current to dc voltage module.
These two signal conditioning
modules can convert up to
400 Vac or 5 Aac signals to 0~5
Vdc signals for data acquisition
cards to measure while
reducing the harmful effects of
ground loops, field noise and
electrical interference. Both
modules provide 1,000 Vdc
between output and power, as well as 2,500 VRMS between input and
output and between input and power. The 3112 provides three input
modes, 0~120 Vrms, 0~250 Vrms and 0~400 Vrms in one single signal
conditioning module.
Advantech, Industrial Automation Group; 800/205-7940;
www.advantech.com/ea
Wireless Monitoring System
Industrial-focused wireless monitoring solutions are designed for
monitoring and controlling processes in difficult industrial and
hazardous applications.
Through a comprehensive
system of transmitters,
receivers, transceivers
and interface gateways,
these solutions offer both
one- and two-way wireless
monitoring. The product line
is complemented by accessories including high-powered antennas for
long-distance communications and explosion-proof enclosures for
hazardous application. Each device offers a wide selection of digital,
analog and pulse inputs that allow fewer radios per system.
Cooper Crouse-Hinds; 866/764-5454; www.crouse-hinds.com
Convert Modicon To A-B
I/O wiring conversion system helps users migrate existing control
platforms to the Allen­-Bradley ControlLogix programmable
7/16/09 11:46 AM
Industrial Networking
Q3 • 2009
Industrial Networking
25
Q3 • 2009
25
Contact us
555 W. Pierce Rd., Suite 301, Itasca, Illinois 60143
630/467-1300 • Fax: 630/467-1124
industrialnetworking@putman.net
POE INJECTORS
Three new four-port 802.3af PoE injectors
address applications where multiple
data/power connections are required.
The BT-CAT5-P4 series injectors feature
industrial-grade cast-aluminum housings
and shielded RJ45 jacks for EMI suppression.
BT-CAT5-P4-4848 ships with a 48 W power
supply, and BT-CAT5-P4-4870 ships with a
automation controller (PAC). Users can
now replace Modicon 800 Series I/O
racks with the ControlLogix I/O system
without disturbing field wiring. The
swing-arm conversion system takes the
existing Modicon 800 I/O swing arm and
converts the field terminations to match a
compatible ControlLogix I/O module. The
ControlLogix I/O system allows users to
keep the same panel footprint.
Rockwell Automation; 800/223.5354;
www.rockwellautomation.com/solutions/
migration
Editorial team
Editor In Chief
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Managing Editor
Digital Managing Editor
Senior Technical Editor
Senior Technical Editor
Editorial Assistant
Art Director
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Walt Boyes
Dan Hebert
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Design & Production team
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publishing team
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Ad Traffic Supervisor
Director of Circulation
Group Art Director
Keith Larson
Anetta Gauthier
Jack Jones
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subscriptions
888/644-1803
sales team
70 W power supply. The standard model
BT-CAT5-P4 doesn’t include a power supply
but can be used with a user-supplied ac or
dc power supply up to 60 V.
L-Com Global Connectivity; 978/682-6936;
www.l-com.com
INTERFACE MODULE
SHDSL MODEM
DSUB series of DIN-rail-mounted interface
modules provides a plug-and-play interface
for industrial control systems, ideally in
packaging and automated assembly. These
Ruggedized 3231 managed SHDSL modem
features a front-panel touchpad and
extends industrial Ethernet connections
Northeastern and Mid-Atlantic Regional Manager
Dave Fisher • dfisher@putman.net
24 Cannon Forge Dr., Foxboro, Massachusetts 02035
508/543-5172 • Fax: 508/543-3061
Midwestern and Southern Regional Manager
Greg Zamin • gzamin@putman.net
555 W. Pierce Rd., Suite 301, Itasca, Illinois 60143
630/467-1300 • Fax: 630/467-1124
Western Regional Manager
Laura Martinez • lmartinez@putman.net
218 Virginia, Suite 4, El Segundo, California 90245
310/607-0125 • Fax: 310/607-0168
Inside Sales Manager
Emily Rogier • erogier@putman.net
555 W. Pierce Rd., Suite 301, Itasca, Illinois 60143
630/467-1300 • Fax: 630/467-1124
e-Marketing Account Manager
Jenny Fanning • jfanning@putman.net
555 W. Pierce Rd., Suite 301, Itasca, Illinois 60143
630/467-1300 • Fax: 630/467-1124
reprints
CE-compliant modules come with male and
female D-subminiature connectors and are
available as nine-, 15- and 25-pin models.
Optional D-SUB cables are available.
Specifications include 1 A maximum
current, 22-14 AWG wire range and -10 to
50 °C operating temperature.
Omega Engineering; 888/55-omega;
www.omega.com
up to 9.4 km. Password-protected
local and remote management options
enable the device to work with any
existing network management policy.
The universal management solution
includes SNMP monitoring, Telnet and
Web management, plus troubleshooting
via remote-loopback. FlexKey touchpad
with backlit LCD provides the ability to
configure with no tools or computer. The
modem transmits data at 4.6 Mbps over
distances up to 3.3 km.
Patton; 301/975-1000; www.patton.com
FosteReprints
Claudia Stachowiak • claudia@fostereprints.com
866/879-9144 ext.121 • www.fostereprints.com
ad index
Advertiserpage no.
AutomationDirect..................................................... 2
Beckhoff Automation............................................... 6
GarrettCom................................................................23
Moxa Technologies................................................... 4
N-Tron............................................................................ 9
Omega Engineering................................................. 3
NEW on the web
For a description of Siemens’ new Simatic ET 200pro IWLAN wireless I/O module, which
is based on IEEE 802.11 WLAN standards and supports deterministic iPCF (industrial
point coordination function), browse to www.IndustrialNetworking.net/siemens.
IN09Q3_24_25_Products.indd 25
ProSoft Technology................................................11
Sealevel Systems.....................................................19
Schweitzer Engineering Laboratories..............27
Transition Networks...............................................28
7/16/09 11:47 AM
26
Industrial Networking
p a r i tfFIRST
y
irc
s th ebBIT
ci tk
Q3 • 2009
A while ago, our instrument specialist
made the rounds of remote multiplexor panels to
check for power-supply failures. In recent years,
we’ve been a little alarmed to find one of the two
redundant dc power supplies failed. We unknowingly
were limping along on a single power supply, at risk of
losing an entire node of multiplexed I/O.
These measurements are “indicate only,” mostly
thermocouples and RTDs, not essential to the
when I tell
an operations
supervisor, “Nothing
bad should
happen, but there’s
a chance you’ll
lose all 120
temperature
indicators in Area K,”
the response
is: “Can you do
this on someone
else’s shift?”
John Rezabek
jrezabek@ispcorp.com
IN09Q3_26_ParityCheck.indd 26
cruising along bumplessly for years. But a sudden
failure of one of these switches, or even a node
becoming isolated, would be pretty troubling. I’m
not even sure if I can get spare parts. Why aren’t
I pulling in some of its diagnostics, or at least
viewing them directly on occasion? More modern
industrial switches have support for Modbus and
OPC, which might make it simpler for an end
user to configure, display and trend some of the
Diagnostics—Use What You Have
functioning of the plant. Nonetheless, losing an
entire bank would be unnerving for operators.
What’s a little ironic is that this power-supply
health information is available through the
multiplexor system’s standard diagnostics, over
the same Modbus 485 link through which we
get the process data. If we just set up the serial
interface to query a few more registers, we’d have
access to a wealth of diagnostics—not only powersupply status, but individual I/O card statuses,
communication status and more.
The same is true of a number of other devices
connected through serial interfaces, including
analyzers, flow meters and small PLCs. Why aren’t
we making full use of the diagnostics we have?
One of the challenges is the time it takes
to decode and test the diagnostics available.
This data often is a bit string, so the developer
or end user has to figure out which bits mean
what and whether a zero is good or vice versa.
Testing sometimes can be a challenge. If you have
to fail something, you risk a potentially wider
malfunction. Usually when I tell an operations
supervisor, “Nothing bad should happen, but
there’s a chance you’ll lose all 120 temperature
indicators in Area K,” the response is: “Can you do
this on someone else’s shift?”
Especially when hardware is reliable,
implementing diagnostics like these, which require
a little effort, becomes a task akin to reading the
manual—that is, no one bothers until something’s
broken. But it only takes a few small victories
to convince your boss that the effort needn’t
repeatedly return to the back burner.
One of the common pieces of hardware that fall
in the category of “reliable and therefore forgotten”
is the Ethernet switch. I have a pair of 3Comm
Superstack switches—my system supplier doesn’t
even recommend them anymore—that have been
switches’ more interesting statistics.
A very rudimentary diagnostic is to try to
capture or derive a status for the points coming
in over a serial link. Our implementation has
the unlucky feature of holding last value—flatlining—on communications loss, like one would
experience if both redundant power supplies
failed. To implement status, we first have to choose
a variable type that supports status and then
either do an “AND” of some selected diagnostic
bits and set the point’s status accordingly or test if
at least the “comm. Fail” state is flagged correctly
by the serial interface device. If you already are
living with a configuration that includes hundreds
of such points, this could be a long effort. It’s much
easier to implement when you’re deriving your
templates early in the design phase. Some systems
support classes of modules, which can be a path
for mass-editing of a class of module, such as serial
Modbus data points.
Another interesting diagnostic that end users
could exploit more is the “AO Readback” variable
of HART valve positioners. This represents the
actual valve position as seen by the positioner. To
get it, you need a HART-capable I/O card. Patching
it back from an asset-management system—using
OPC, for example—could be a little dicey, as the
possibly long and variable latencies make the
potential for stale data large. Some HART polling
applications can take a long time—hours—to
cycle through all the HART devices.
By making full use of diagnostics we already have,
we not only help our enterprise and the people who
come after us, we encourage and push our supplier
counterparts to provide us with diagnostics that are
timely, meaningful and easily accessible.
John Rezabek is a process control specialist at ISP
in Lima, Ohio.
7/16/09 11:49 AM
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IndNet_2725_Aug09_A5.indd
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1:36:30
7/17/09 1:54
PMPM
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CM
MY
CY
CMY
K
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7/15/09 11:05 AM