belden whitepaper industrial ethernet
TRANSCRIPT
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Industrial Ethernet is trending to be the principal infrastructure choice for mission-criticalindustrial automation and control applications. Industrial Ethernet is built on the samestandards-based networking platform as enterprise Ethernet, which has long reigned as theuniversal network solution.
Industrial Ethernet connects the office with the plant floor by utilizing a single cabling platformwith Ethernet connectivity and IP addressing. This convergence of open, standards-basedEthernet communications provides all the advantages of secure, seamless interoperability amongmanufacturing enterprise networks from corporate offices to the shop floor and enablesInternet and enterprise connectivity, anytime and anywhere.
In addition to system integration and interoperability, there are a host of other benefits to begained from implementing a complete, end-to-end Ethernet solution from cabling andconnectivity, to active components and associated hardware.
Key business benefits include lower overall Total Cost of Ownership (TCO) and higher return oninvestment (ROI) resulting from real-time visibility and flexibility, reduced network maintenanceand administration costs and labor, and greater physical and virtual network security.
Operational benefits at both the plant and enterprise levels include:
Faster and less costly plant upgrades, expansions and changeouts Access to real time data to improve overall plant operations Faster installation, remote troubleshooting and corrective action capabilities
Real time inventory visibility
Collaborative reviews of production data and virtual support groups
Increased production capacity
Shop floor system integration with ERP for scheduling, planning, quality trackingand delivery information
Network Infrastructure Risks in Extreme Environments
Industrial communications and control networks are expected to operate consistently andreliably under extreme conditions, such as electromagnetic interference (EMI), high operatingtemperatures, ambient outdoor temperatures, power/voltage fluctuations, machine vibration,mechanical hazards and more.
For example:
In the Oil, Gas and Petrochemicalindustry, signal transmission components typically haveto withstand the destructive effects of temperature extremes, humidity, moisture, dust, mudoil and solvents, and the potentially corrosive effects of chemicals.
In Water and Wastewatertreatment plants, the cabling, connectivity and networkingdevices must endure high levels of humidity, grit and sludge, and, in some cases, are exposedto lime, as well as corrosive gases such as methane, hydrogen sulfide and chlorine.
In the rapidly growing Wind Powerindustry, signal transmission components in windenergy sites, whether on-shore or off-shore, are routinely exposed to temperature extremes,excessive moisture and humidity from rainfall, mist, and fog. Mechanical and electricalstressors may include vigorous, prolonged vibration, torque, damage from rodents, EMIinterference, and even lightning strikes.
In the Miningindustry, environmental conditions are extremely harsh. Dust, dirt anddampness can threaten signal transmission equipment and performance. In some mines,caustic chemicals and potentially explosive ambient conditions exacerbate the threat. Whilethe use of conduit, aerial fiber optic cabling and wireless communications can alleviatesome risk, mining remains one of the most challenging industries for industrial networking.
A Robust Industrial
Ethernet Infrastructure
Consisting of Environmentally
Hardened Network Cabling,
Connectivity, and Active
Components Is Essential
to Long-Term Performance
and Reliability
Table of Contents
Network Infrastructure Risks . . . . . . . . . . . . . . .1
Network Safety, Uptime and Control . . . . . . . . .2
Costs of Network Failure. . . . . . . . . . . . . . . . . . .2
Commercial-grade Components . . . . . . . . . . . .3
Ethernet Hardware Comparison. . . . . . . . . . . . .4
Features of Industrial-gradeEthernet Products . . . . . . . . . . . . . . . . . . . . . . . .5
Industrial Ethernet Cables . . . . . . . . . . . . . . . . 6-9
Industrial Ethernet Switches. . . . . . . . . . . . 10-11
Matching Hardware Componentsto Applications . . . . . . . . . . . . . . . . . . . . . . . . . . 12
Conclusion . . . . . . . . . . . . . . . . . . . . . . . . . . . . .12
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Given these environmental risks, it isclear that the networked communicationssystems in extreme environments must beexceptionally rugged and durable. Anyphysical deterioration or electrical failurein key data transmission components canlead to unreliable network performanceand/or safety issues, and may ultimatelylead to loss of critical data, costly downtime,or even catastrophic failure.
Network Safety, Uptime and
Control Are Paramount
Industry is a broad term encompassinga multitude of diverse operations fromdiscrete manufacturing of every kind, toprocessing of foods and beverages, pulp andpaper, chemicals, oil/gas and petrochemicals,to commercial and government sites such aspower generation plants, wind energy farms,
water and wastewater treatment facilities,airports and transportation hubs, militarybases, ships and shipyards, railyards, tunnels,dams and bridges.
Networks in all of these operations mustperform in extreme and often hazardousenvironments and every operation has its ownset of environmental challenges to contendwith. Analysts report that an overwhelmingpercentage of unplanned downtime inindustrial operations can be attributed tonetwork infrastructure failure. According toone network management report, fully 72percent of network faults can be attributedto failure at the OSI (Open SystemsInterconnection) Layer 1 (Physical Media),Layer 2 (Data Link) and/or Layer 3 (Network).
Untimely and costly disruptions can largely beprevented by installation of a robust networkinfrastructure utilizing environmentallyhardened, industrial-grade components in allthree OSI layers. A ruggedly designedframework enables industrial enterprises tocarry out their mission-critical functions byproviding the highest possible levels of:
Safety.Optimum safety is critical in allindustrial operations. Full safety demandsfail-save reliability and redundancy of datatransmissions, as well as network componentsthat meet and exceed industrial requirementsfor potentially hazardous environments.
Uptime.Prevention of signal transmissionproblems is a major factor in ensuringconsistent and dependable network uptimeand plant productivity. Whether an operationinvolves a discrete manufacturing facility,a processing plant or an infrastructure site,such as an airport or power generation plant,keeping operations running smoothly andreliably assures optimum uptime andpeace of mind.
Control. Continuous monitoring, managementand control, as well as operational efficiency,require continuity in data transmission andnetwork availability. Any network failure, andsubsequent downtime, can result in severeand extremely costly consequences.
The RealCosts of Network Failure
Industrial plants rely heavily on theirautomation, instrumentation and controldata communications to relay signalsbetween devices, machinery and the controlsystem to activate events on an exacting andpre-determined schedule, with little or nomargin for error. Many industrial facilitiesare sizeable and their networking productsmust meet or exceed stringent industrialregulations and ratings. Users also desireoptimal manageability and security sothat network availability attains 99.999%uptime or better.
Oil, gas and petrochemical plants, water and wastewater facilities, wind farms and mines are just afew examples of industrial operations in which extreme environmental hazards can be detrimental to theperformance and reliability of commercial-grade Ethernet cabling, connectivity and networking devices.
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Maximum productivity with minimaldowntime is a key goal, and 24/7 networkperformance and reliability are critical toachieving that goal. No matter what theindustry, if a switch, connector or cablingsystem in the plant fails, the cost of partsreplacement and repair represents only a tinyfraction of the overall costs associated with
production downtime.
For example, if a cabling system componentor Ethernet switch fails in a power generationfacility, the repair/labor costs alone could be15-20 times the cost of the component itself.However, disruptions in the plants flow ofinformation or control signals could lead topower outages which, even today, cost thepower generation industry as much as $150billion per year. Downtime in an automotiveassembly plant capable of producing onevehicle per minute would stand to lose profitsof about $2,000 to $3,000 per minute for
small car production, and up to $8,000 perminute for SUV and pick-up truck production!
The indirect costs of Ethernet system failurein any industry must take into account lostproductivity, delayed downstream processes,cost of system shut-down and start-up, andthe potentially devastating loss of service tocustomers relying on the plants mission-critical output. Depending on the industryand overall operating costs, these indirecteffects can send total downtime costssoaring to hundreds of thousands, evenmillions of dollars.
That is why investing in a high-quality,rugged Ethernet infrastructure designedspecifically for use in harsh environments is awise business decision one that can providetremendous peace of mind to networkengineers and administrators and theorganizations they serve.
Commercial-grade Components
Are Not the Solution
In a typical office, the Ethernetinfrastructure is installed in a relativelyclean, quiet environment with cables hiddenbehind walls, in ceilings or under floors andnetwork switches, hardware and connectivity
components sheltered in protected areas.Industrial facilities present a very differentreality. Here, many if not most cables,connectors, switches, and active networkcomponents are integral to machineautomation, instrumentation and controlsystems, which places them in harsh andpotentially hazardous situations. Even thebest Commercial-Off-The-Shelf (COTS)Ethernet systems are not made to handle suchconditions over time. Rugged conditions callfor ruggedized cables and only industrial-grade Ethernet system components are builttough enough to withstand the hazards andrisks they are exposed to day after day.
Consider, for example, the deleterious effectsthe following common environmentalconditions can have on network components:
Temperature Extremes.Extreme coldcan make COTS cables stiff and brittle,while elevated temperatures can degradethe plastic used in the cables constructionand cause an increase in attenuation.Industrial-grade cables are available thatwill operate in a wider temperature range(-40C to +85C) than commercial cables(0C to +60C).
Commercial-grade hardware (switches,etc.) is designed to operate from 0C to+40C, while industrial Ethernet hardwarecan operate efficiently from 0C to+60C extendable to -40C to +85C(conformal coating also available forhumid/moist applications).
Chemical Exposure.Oils, solvents,chemicals and cleaning solutions can soakinto COTS cables, especially under heat,causing the cable jacket to swell and losemechanical strength.
On the hardware side, corrosive chemicalscan damage the electronics in commercialswitches, whereas ruggedized industrialswitches are securely sealed to preventingress of these substances.
Humidity Levelsof up to 99 percentcan be accommodated by industrial-gradeswitches, which can also be sealed tomeet IP67 standards.
UV Radiation Exposurecan causeCOTS cable jackets to decompose atan accelerated rate, compromisingmechanical strength and electricalperformance.
Physical Hazards. The factory floor
holds many mechanical risks, especiallyfor machine automation cables andconnectors. Excessive machine movementor vibration can result in cables beingpulled or stretched with excessive force,which can create imbalance between thepairs, degrade electrical performance, andincrease susceptibility to ambient EMI/RFI.Plant floor vehicles, such as forklifts andmoving carts, can accidentally run overcables, causing abrasion, crushing orcut-through.
Even well-made, properly installed COTS
Ethernet components are not constructedto survive these kinds of hazards. Onlyhardened, industrial-grade componentsare robust enough to withstand theenvironmental challenges present everyday in industrial settings.
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Industrial Ethernet Hardware vs. Typical Office-grade Ethernet Hardware
Characteristics(Hub / Switch / Fiber Interfaces) Industrial Ethernet Hardware Typical Office-grade Ethernet Hardware
Operating Temperature 0C to +60C standard, with extended temp of -40C to 0C to +40C+85C and conformal coating available
Humidity 99% (non-condensing); 100% using IP67 (waterproof) switches Typically 10-85% (non-condensing)
EMC EN50082-2 EN50082-1
Operating Voltage Variety of voltages, but 24 V (redundant) 120 / 240 Vbeing the most common/standard Internal power supplyNo internal power supply
Redundancy Media ring reconfig time < 30ms and as Depending upon topology,low as 10 ms. possibly significantly more
Link Media Multimode / Single-mode / UTP/STP Multimode / Single-mode / UTP/STP
Communication Distances Up to 68 miles longhaul single-mode Up to 68 miles longhaul single-mode
Management SNMP (Simple Networking Management Protocol) SNMP (Simple Networking Management Protocol)WEB-Based Management WEB-Based ManagementSerial (RS232) Serial (RS232)CLI (command line interface) CLI (command line interface)EtherNet / IPand PROFINET profiles forintegration of management into PLC/HMI
Diagnostics Fault relay output(s) e.g., to PLC LED (visual information)I/O Port LED (visual information)SNMP trap to OPC server
Chassis- Material Plastic / Metal Plastic / Metal
- Dimensions Small (e.g. 80x140x85 mm) Medium (e.g. 440x70x380 mm)
- Mounting DIN rail / Rack Desktop / Rack
Approvals CE, cUL 1950, UL508, FCC Part 15, Germanic Lloyd, CE, cULClass 1 Div 2, IEC 61850-3, IEEE 1613, NEMA TS2,EN 50121-4, EN 50155
Vibration 2g (IEC 60068-2-6 FC) Typically not rated/tested
Shock 15g+ (IEC 60068-2-27) Typically not rated/tested
Cooling System Fan-less operation Fan Operation
Resistance RFI/EMI, dust, oil (even IP67) Dust
Data Throughput 10Mb, 100Mb, 1Gb, 10Gb 10Mb, 100Mb, 1Gb, 10Gb
Switches Yes (DIN rail, 19 rack and hard mount) Yes (19rack or tabletop)
Hubs Yes (DIN rail) Yes (19rack or tabletop)
Transceiver Yes (DIN rail) Yes (19rack or tabletop)
Firewall Yes (DIN rail) Yes (19rack or tabletop)
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Ruggedized for High Mean
Time Between Failure
In selecting physical media, data links andnetwork hardware for the industrial Ethernet,multiple factors should be considered toensure optimal performance, ease ofmaintenance, and long-term reliability.
Ruggedized industrial Ethernet products havebeen designed specifically to network in toughenvironments, to support the industrialprotocols which are being transmitted acrossthese networks, and to accommodate theenvironmental rigors of the location. Keyconsiderations in specifying industrial-gradenetwork components include:
MTBF (Mean Time Between Failure).Industrial Ethernet products are designed toprovide the same lifespan as other automationcomponents typically 10 to 30 years ormore. By comparison, typical commercial-
grade products are built to achieve a 5-yearaverage lifespan.
Mounting options.Industrial Ethernethardware devices are usually DIN rail mountedor bolted directly onto the machines thatreceive transmitted data.
Small form factor. Equipment is typicallydesigned to occupy less space to allow greaterdensity within a control panel.
Ventilation without fans.Industrial Ethernetdevices rely on passive heat dissipation.
Protection class.Devices must be available
in dustproof and waterproof housings.
Conformal coating.A special coatingis applied to PCBs to protect electroniccomponents in damp or corrosiveenvironments.
Redundancy.Redundant power, redundantmedia paths and even redundant devices canassure 24/7 uptime.
Bandwidth.With an ever-increasing numberof Ethernet-enabled devices being added tonetworks, sufficient bandwidth is needed toensure meeting future needs.
Hardened Components Protect
Network Integrity
As stated previously, an overwhelmingpercentage of network performance problemsare due to failure at OSI Layer 1, Layer 2 orLayer 3. Therefore, it is critical to ensure thatcomponents at all three layers physicalmedia, data links and active network devices
are designed and constructed to withstandthe operational and environmental stressorsto which they are subjected. For each category,multiple factors need to be considered toensure optimal performance, ease ofmaintenance, and long-term reliability ofthe mission-critical network.
Physical Media
Cabling & Connectivity
For the physical media layer, there are a hostof products in todays marketplace that fullyconform to the Ethernet LAN.IEEE 802.3standard. Selection will depend on eachplants network configuration and applicationrequirements. Products include:
Heavy-duty, all dielectric, indoor/outdoor-rated optical fiber cablingin single-mode and multimodeconstructions. Many feature water-blocking agents for added protectionin moisture-laden environments.
Industrial grade Cat 5e (2-pair and4-pair) and Cat 6 UTP (4-pair) cableswith heavy-duty oil- and UV-resistantjackets. Some Category cables feature aBonded-Pair inner construction in whichthe conductor insulation of the pairs isaffixed along their longitudinal axis toensure consistent conductor concentricity
to prevent any performance-robbinggaps between the conductor pairs duringinstallation and use.
Upjacketed and armored cables for moreextreme environments.
Continuous flex cables designed foruse with continuous motion machinesand automation systems.
Low smoke zero halogen (LSZH)cables, waterblocked and burial cablesare also available.
Cables designed for use with leading
industrial automation networking andcommunications protocols, such asEtherNet/IP (ODVA), Modbus TCP/IP,ProfiNet and Fieldbus HSE.
Industrial-grade connectivity components,such as: IP67- or IP20-rated UTP or FTPpatch cords, connectors, modular jacks andplug kits, adaptors, faceplates and surfacemount boxes.
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Fiber optic Ethernet cablesrepresent
the ultimate in future-proofing and are
available for indoor use (riser or tray)
or outdoor use (including direct burial).Typical designs use multimode fibers
in a loose tube configuration, usually
available in 2- to 72-fiber constructions.
For plenums, tight buffered, 2- or 6-fiber
single-mode or multimode construc-
tions are typically available.
To handle Gigabit Ethernet light
sources and any expanded bandwidth
requirements some cables use a
laser-optimized fiber.
For moisture protection, a water-
blocking agent should be included
in the cables construction.
In particularly harsh environments,
a CPE outer jacket will provide addi-
tional protection against chemicals or
abrasion; an armor tape or aluminum/
steel armoring may also be appropri-
ate for the extreme environments,
including some burial situations.
Ratings include: UL Type: OFNR,
cUL Type: OFN FT4, IEEE 383-2003
Flame Test.
Copper Ethernet cablesare the
more traditional option in industrial
installations, available for either Cat-
egory 5e or Category 6 applications.
Category 5e cables are the dominant
choice today, while Category 6 cables
are finding increasing use where Giga-
bit speeds and increased bandwidth
are desired and/or for future-proofing
purposes. Category 5e and Category 6
twisted pair cables are available using
any number of conductor types,
insulations, shielding and jackets.
Armoring is also available for extremelyharsh environments.
Construction selection criteria:
Unshielded or shielded?
Unshielded products can be used
in most environments; shielded
products are recommended for
especially high noise environments.
Shields: Typically a foil or braid
is used to protect the integrity
of the signal and to screen out
any undesirable interference or
noise. However, to provide extra
durability and noise protection, a
foil/braid combination can be used.
Solid or stranded conductors? Solid
conductors are appropriate for most
installations; stranded conductors
provide extra flexibility for better
handling in close environments. For
robotic/continuous flex applications,
use of a cable with a highly stranded
conductor is recommended.
Pair conformity/centricity:
Bonded-Pair cables provide resis-
tance to the rigors of installation by
utilizing a manufacturing technique
that affixes the insulation of the cable
pairs along their longitudinal axes
so no gaps can develop between the
conductor pairs; a nonbonded-pair
cable construction can be susceptible
to pair-gapping during installation
(and impedance mismatches).
Insulations: Most industrial-grade
Ethernet cables utilize a polyolefin
insulation. For extreme temperatures,
however, an FEP insulation (andjacket) is recommended.
Jackets: Oil- and sunlight-resistant
cables typically have a PVC jacket.
If the cables are exposed to moisture,
a waterblocking agent should be
part of the cables construction, as
well as inner and outer PE jackets if
the cable is buried. Gas-resistance
calls for an FEP-jacketed cable, while
low smoke zero halogen (LSZH) PVC
jackets are available for environments
where smoke/flames are a risk. For
extreme temperature environments,
the cables should feature an FEP
jacket (for an extended operatingtemperature of -70C to +150C).
And, for continuous flexing or robotic
applications (which could include
the complication of weld splatter),
cables with TPE inner and outer
jackets are recommended.
Industrial Ethernet Cable Selection
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Commercial cable after 25 cycles.
Industrial cable after 25 cycles.
The Proof is in the Testing
A series of rigorous tests conducted by Beldenon COTS cables versus industrial-grade cableshas proven that the COTS cables simply do notstand up as well as industrial-grade Ethernetcables in harsh environments. All nine testswere performed on state-of-the-art testing
equipment, and all the cables used in thestudy initially tested asfully compliant to ANSI/TIA/EIA 568-B.2 Cat5e standards. Following is a summary of testsperformed and the results:
Abrasion.Using a fixed drum covered withsandpaper, cables were stretched across aportion of its circumference, then moved backand forth cyclically for 25 cycle counts. Atthat point, the conductors of the COTS cablecould be seen through breaks in the jacket,which would cause it to lose mechanical andelectrical integrity. The pairs of the armoredindustrial cable were not compromised.
Cold Bend. Conducted per UL 444,samples of cables were left in a controlledtemperature and humidity chamber called acold box. They remained for one hour priorto testing. They were then tested (at -80C,-60C, and -40C) by being partially woundaround a 3-inch diameter horizontal mandrelwith one end of the cable under tension
from an aluminum weight. The cables werethen unrolled and visually inspected to checkfor cracks in the jacket. The COTS cablebecame brittle and showed visible cracks.The industrial-grade high/low temp cablehad no visible damage.
Cold Impact. In this test, also conductedper UL 444, an aluminum weight wasdropped down a hollow guide-tube to smashagainst a segment of cable under test. Theimpact force delivered 24 in-lbs or 2.7 joulesof impact energy. Each length of cablehad been previously cooled; and a total often samples were inspected at a series of
increasingly lower temperatures to determineif the cables jacket integrity was damaged,a condition which could allow ingress ofchemicals and moisture and could potentiallead to a conductor-to-conductor shortor even catastrophic failure. The standardjacketed COTS cables failed at -20C. Theindustrial-grade cables, protected byhigh-low temperature jackets, did notcrack until impacted at -70C.
After the cold box, the cables were partially woundaround a mandrel and subjected to the tensionexperienced through the use of an aluminum weight.
The test set-upwith the cables on a xed drumcovered with sandpaper.
In the cold bend test, the cables were rstplaced into a cold box.
In the cold impact test, after the cable is cooledan aluminum weight smashes against it.
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Crushing. In this test, an Instron machinehead brings a 2-inch by 2-inch plate downon a segment of cable to crush it withfailure defined as the point at which thecable would no longer reliably supportCat 5e performance. Each cables electricalcharacteristics were measure throughoutthe testing. At 400 lbs applied force, the
COTS cable with PVC jacket failed it wassmashed flat and would not spring back toits original shape.The industrial-grade,black-jacketed armored cable had afailure value of 2,250 lbs over a ton.
Cut-Through.In this test, based on CSAstandard #22.2, a chisel-point mandrel on anInstron machine was lowered onto a segmentof cable to test the cables susceptibility to acut-through leaving the conductor exposed.Several kinds of cable were sliced by thechisel to the point where a short circuitwas sensed across the conductors, creating
a potentially hazardous situation. The COTScable shorted out at 92 lbs of applied force.Two unarmored industrial-grade cablestook 205 lbs and 346 lbs of applied force toshort. The armored industrial cable took346 lbs applied force to pierce the armor;however, the conductors did not short untila force of 1,048 lbs was applied.
High Temperature.In this test, three spoolsof cable were suspended from a mandrel in ahigh-temperature oven. The blue cable in themiddle is a COTS Cat 5e cable with standardPVC jacket. The two are black industrial-gradeCat 5e cables, one with a PVC jacket, theother jacketed in FEP. All cables were firsttested at an ambient temperature of 20C and
were then tested again after being exposedto a high temperature of 60C over time. TheCOTS cable functioned acceptably at 20Cbut, over time, at 60C, attenuation increasedto where the cable would not support a rundistance of 100 meters. The industrial-gradecables, even after exposure to 60C overtime, continued to support the maximumrun distance.
The Instron crushing device.
The COTS cable is smashed at and fails at 400 lbs.
The industrial-grade armored cable fails only after aton of crush pressure.
The cables were tested, as suspended,in a high temp oven.
A chisel-point mandrel on an Instron machineperforms the cut-through procedure.
COTS vs 7928A vs 7922A Cat 5e
Attenuation at 20C and 60C
Atten(d
B)
Freq (MHz)
1009080706050403020100-30
-25
-20
-15-10
-5
0
The industrial-grade cable showedlittle attenuation even at 60C.
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Oil Resistance.In this test, conducted perUL 1277, lengths of cable were immersedin containers of oil, which in turn wereimmersed in a water bath that was placed ina chamber held at 125C for 60 days. Afterthe test period, cable segments were removedand their jackets evaluated for tensile andelongation properties. Exposure to oil and
lubricants can make jacketing brittle andfragile, even at room temperature, resultingin loss of mechanical properties and reducedservice life. The blue COTS cable showed signsof this type of deterioration. The industrialcables jacket did not, because thematerials and jacket thickness are ratedfor exposure to oil and other substances,even at elevated temperatures.
UV Exposure. In this procedure-basedASTM G 154 test (Standard Practices forOperating Fluorescent Light Apparatus forUV Exposure of Non-Metallic Materials),segments of various cables were affixedto panels that were mounted so that thecables directly faced a fluorescent lightsource whose output range was adjusted
to match that of solar radiation levels. Thecables were exposed to light for 720 hours(30 days), then their jackets were visuallychecked for discoloration, as well as forsigns of degradation in tensile strengthand elongation. The COTS cable was notsunlight-resistant and their jackets showeddiscoloration, a precursor to degradation ofthe jacket material. The industrial-gradecables were rated to resist the effects ofsunlight and other UV sources and showedno jacket damage.
Water Immersion.In this test, theelectrical properties of the cables (primarilyattenuation) were measured initially. Thenthe cables were coiled into a dry container,and water was added to submerge them.The cables were tested intermittently overa six-month period. The COTS cable showedincreased attenuation as soon as the cable
was immersed in water and this continued todegrade over the half-year immersion. Aftersix months of immersion, the industrial-grade cable showed only a slight increasein attenuation and the cable stillexceeded the Cat 5e requirements.
The UV exposure test is based uponASTM procedures.
The oil bath test, conducted as speciedin UL 1277.
The water bath test is a six-month long test,with the cables fully submerged in water.
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Wireless or Wired?
While wireless has its advantages
in industrial applications, it is poorly
suited for transmitting time-sensitive
control data that could adversely
affect productivity or safety.
Wireless
Pros:Provides mobility and network
flexibility. Limited cabling costs.
Overall convenience.
Cons:Not as reliable or as secure
as a cabled solution. Larger and more
complex networks require a site survey.
Achieving long distance communica-
tions reliably can be very difficult.
Wired
Pros:Significantly more reliable andsecure. Far higher data speeds are
possible up to 10 Gigabit with some
wired switches.
Cons:Lower flexibility. High initial cost
of cabling and the cost of relocating an
Ethernet device (if it will not be close
to a network connection/port).
DIN Rail, 19" Rack or Panel Mounted?
The mounting choice/preference will
dictate which products are applicable.
DIN Rail Mount:Managed andunmanaged open rail switches,
unmanaged switches, and wireless
Ethernet devices.
Rack Mount:Some suppliers offer a
DIN rail adapter for 19" racks, permit-
ting multiple DIN rail mount devices to
be mounted inside a 19" rack.
Panel Mount: A variety of switches
and wireless Ethernet devices are
available, some with adapters for
panel mounting. Some companies
offer ultra-rugged switch options foruse in extreme environments.
IP67 Ethernet Connectors?
IP67-rated connectors are ideal
for use in extremely damp/wet
environments and applications where
significant vibration could result in
intermittent communication from
connector contact deterioration. The
connector, approved by the ODVA
(Open Device Vendor Association), is
the M12 D-code Ethernet connector
a 4-pin connector that uses CAT 5e or
better (2-pair).
The IP67/waterproof connector
solution is typically available as field-
installable connectors or pre-terminated
and overmolded patch cords (single
M12 or RJ45 or double ended M12-M12,
M12-RJ45 and RJ45-RJ45). A bulkheadM12 is an excellent solution for migrat-
ing the Ethernet cable from the inside
of the control panel to the outside.
Keep in mind that the IP67 rating is
not always used in wet environments or
applications where vibration is an issue:
Some users choose instead to deploy
all M12 D-code connectors so that they
can eliminate control panels.
Managed or Unmanaged Switches?
A classic analogy for management
has always been the dashboard and
electronics of a car:
A managed switchis akin to a car with
a dashboard and an unmanaged switch
is one without. A managed switch can,
through web browser access (secured
by password), control certain internal
switch functionality that may be criti-
cal to the flow of data and the function
of the network. A managed switch also
has the ability to inform and react to
certain conditions and provide a level
of security, making it an ideal solution
for an application with a higher need for
uptime (where control data, rather thanmeasurement data is transmitted).
An unmanaged switchhas none
of this functionality and is typically a
plug-and-play switch and is best used
on smaller stand-alone applications or
as an edge-switch in a larger network.
Ethernet Switch Selection Options
12
43 Pin
1234
Housing: shield
Function
TD + Transmit Data +RD + Receive Data +TD - Transmit Data -RD - Receive Data -
This Hirschmann OCTOPUS switch is idealfor installation in vibration-prone environments.Here, the Ethernet IP67 switch is used to providepassenger compartment video surveillance, aswell as travel updates and entertainment.
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Hardware: Switches, Active Network
Devices and Accessories
A wide range of hardware is available toenable management of industrial Ethernetnetworks at the information, control anddevice levels. There are products to supportboth copper and optical fiber media, as well
as switches capable of data speeds as high as10 Gigabits per second. At a minimum, allof these network components switches,connectors, and other hardware shouldoffer robust construction and resistance tohigh temperatures, vibration and EMI.
The Importance of Redundancy
Another Ethernet factor considered to bean industry best practice for mission-criticalapplications is redundancy, which is extremelyimportant but sometimes overlooked inselecting industrial Ethernet switches. Twospecific kinds of redundancy are key
to maintaining uninterrupted signaltransmission and maximum uptime.
Power source redundancy.Having anuninterruptible power source (UPS) isabsolutely critical to consistent and reliableswitch performance. Specifying switches thathave dual power input capabilities meansthat if one power source fails, the otherimmediately takes over.
Data path redundancy.The daisy-chainnetwork topologies used by many industrialplants to connect automated machinery anddevices have one inherent flaw: if any linkbetween the two switches fails, the entiresystem could potentially go down, as thedevices on one network segment can nolonger communicate with devices in othersegments. The solution is to build in aredundant data path which can take theform of either a ring or mesh topology.
Ring Topology. In a ring configuration,the easier and simpler of the two types,a series of managed switches are daisy-chained and the first and last switch ofthe chain are then linked to form a ring.In the event of a failure in the media orany of the switches, data is automaticallyre-routed, achieving network resiliency
in milliseconds.
Mesh Topology.Mesh topologiesrequire that all switches in the meshsupport STP (Spanning Tree Protocol)or RSTP (Rapid Spanning Tree Protocol).While supported by most managedswitches, this feature can be difficultto configure and network recovery canbe several seconds depending on the
number of switches in the mesh andhow the fail-over is configured.
Temperature and Humidity/Moisture
Typical industrial temperature range
is 0 to +60C
Extended temperature range
components are available from
-40 up to +85C
IP20/IP30/IP67 (95% relative humidity,
non-condensing not applicable
to IP67
IP classifications are governed by
the IEC 429 standard
Mechanical Stability
Shock and vibration tests should
be in accordance with PLC standards
IEC 1131-2, EC 60068
Electric Requirements
EMI: EN 50022-2, FCC part15 (class B)
IEC 1000-4-2, IEC 1000-4-6,IEC 1000-4-4, EN 61000
Certifications
cUL 508 the basic and most
common safety standard for industrial
control equipment
cUL 1604 the standard for Class 1,
Division 2, hazardous locations
IEC 61850-3 the standard for electrical
substation automation networks
IEEE 1613 the standard for
communications networking devices
in electrical substations
EN50155 European specification for
onboard rolling stock/train applications
EN50121-4 European specification
for track-side rail applications
NEMA TS-2 US-based standard for
traffic signaling and communications
ATEX100A, ZONE 2 a standard
required in Europe for hazardous/
explosive environments (similar to,
but not compatible with cUL 1604
Class 1, Div 2)
GL (Germanischer Lloyd) a Germanstandard that has gained global accep-
tance for marine (ship, offshore oil, etc.),
some petroleum and wind industries
Industrial Ethernet Hardware Standards and Specifications
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Be Sure Hardware Components
Match the Application
As with selection of the networks cabling, it iscritical to ensure that the specifications of theactive hardware are suited to the application.Some factors to keep in mind when makingbuying decisions include:
Temperature.Standard PLC requirementsare 0-60C (a standard met by mostindustrial switches), but some applicationscan present an ambient temperature ashigh as 85C and as low as -40C.Note: Although most switches will run atextremely low temperatures, many willnot start up after having been idle.
Moisture. Conformal coating or IP67housing solutions can negate these issues.The IP67 connectivity of choice is theODVA-approved M12 D-code Ethernetconnectors (a 4-pin circular connectorthat is available as a field-installable IP67/waterproof connector or as pre-terminatedpatchcords using Cat 5e with an industry-appropriate jacket material).
Shock and vibration.Even the minutestvibration on a plant floor can wear onthe RJ45 connections over time, causingintermittent data communication. Forapplication such as this, look for switchesthat utilize the M12 D-code connector.
Industry Approvals.While UL508,the requirement for all automationequipment, is a must-have, some oftennegate to take into consideration theother approvals that are common tothe various automation markets.
cUL1604 The standard for Class I,Division 2, hazardous locations
IEC 61850-3 and IEEE 1613 Thestandard for electrical substationautomation networks
EN50155 and EN50121-4 A Railway networking/communicationspecifications
An Industrial Ethernet
Infrastructure Built to Last
Field-proven Solutions Deliver ProvenReliability.The most effective and cost-effective path to ensuring long-termperformance and reliability of the industrialEthernet is to find and invest in networkinfrastructure components designed and ratedspecifically for use in harsh and demandingenvironments. End-to-end industrial-gradeproducts are more ruggedly engineered andconstructed in every way, incorporating designfeatures and materials capable of withstandingthe severe environmental and physical stressorsto which they are subjected every day.
End-to-End Integration Ensures OptimumInteroperability.During the selection process,it is important to take the time to evaluatethe marketplace and select a qualifiedsupplier capable of providing a top-quality,end-to-end Ethernet framework tailored to
the application and environmental conditions.As many adopters of industrial Ethernet havealready discovered, taking a total systemapproach will result in a more integratedsystem with all products seamlessly matched
to deliver interoperability and consistentlyreliable performance day after day, andyear after year.
Conclusion
Most industrial organizations investsignificantly to protect the safety andsecurity of their production processes, andto provide workers with safety and protectivegear, such as hard hats, safety glasses, glovesand footwear. Doesnt it make good businesssense to invest wisely to preserve, protectand defend the data network infrastructurethat supports all of the facilitys mission-
critical information, automation andcontrol functions?
B ld T h i l S t 1 800 BELDEN 1 b ldIEWP 2009
Beldens matched, end-to-end CompleteIndustrial Solution for Ethernet includesHirschmann-branded switches/active networkdevices and networking software, Lumberg
Automation-branded connectivity andBeldencable.
Typical industrial Ethernet hardware is ratedfor temperature ranges of 0 to +60C. MostHirschmann switches offer an extended rangeof -40 to +70 C, or up to +85 C and beyond.
This thermal photograph demonstrates thesuperior heat-resistant performance ofHirschmann industrial Ethernet switches overa typical industrial-grade switch.