Industrial Ethernet is trending to be the principal infrastructure choice for mission-critical
industrial automation and control applications. Industrial Ethernet is built on the same
standards-based networking platform as enterprise Ethernet, which has long reigned as the
universal network solution.
A Robust Industrial
Industrial Ethernet connects the office with the plant floor by utilizing a single cabling platform
with Ethernet connectivity and IP addressing. This convergence of open, standards-based
Consisting of Environmentally
Ethernet communications provides all the advantages of secure, seamless interoperability among
Hardened Network Cabling,
manufacturing enterprise networks — from corporate offices to the shop floor — and enables
Connectivity, and Active
Internet and enterprise connectivity, anytime and anywhere.
Components Is Essential
to Long-Term Performance In addition to system integration and interoperability, there are a host of other benefits to be
and Reliability gained from implementing a complete, end-to-end Ethernet solution — from cabling and
connectivity, to active components and associated hardware.
Key business benefits include lower overall Total Cost of Ownership (TCO) and higher return on
investment (ROI) resulting from real-time visibility and flexibility, reduced network maintenance
and 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
Table of Contents • Faster installation, remote troubleshooting and corrective action capabilities
Network Infrastructure Risks . . . . . . . . . . . . . . .1 • Real time inventory visibility
Network Safety, Uptime and Control . . . . . . . . .2 • Collaborative reviews of production data and virtual support groups
Costs of Network Failure . . . . . . . . . . . . . . . . . . .2 • Increased production capacity
Commercial-grade Components . . . . . . . . . . . .3 • Shop floor system integration with ERP for scheduling, planning, quality tracking
and delivery information
Ethernet Hardware Comparison . . . . . . . . . . . . .4
Features of Industrial-grade Network Infrastructure Risks in Extreme Environments
Ethernet Products . . . . . . . . . . . . . . . . . . . . . . . .5
Industrial communications and control networks are expected to operate consistently and
Industrial Ethernet Cables . . . . . . . . . . . . . . . . 6-9
reliably under extreme conditions, such as electromagnetic interference (EMI), high operating
Industrial Ethernet Switches . . . . . . . . . . . . 10-11 temperatures, ambient outdoor temperatures, power/voltage fluctuations, machine vibration,
Matching Hardware Components mechanical hazards and more.
to Applications . . . . . . . . . . . . . . . . . . . . . . . . . .12
Conclusion . . . . . . . . . . . . . . . . . . . . . . . . . . . . .12
• In the Oil, Gas and Petrochemical industry, signal transmission components typically have
to withstand the destructive effects of temperature extremes, humidity, moisture, dust, mud,
oil and solvents, and the potentially corrosive effects of chemicals.
• In Water and Wastewater treatment plants, the cabling, connectivity and networking
devices must endure high levels of humidity, grit and sludge, and, in some cases, are exposed
to lime, as well as corrosive gases such as methane, hydrogen sulfide and chlorine.
• In the rapidly growing Wind Power industry, signal transmission components in wind
energy sites, whether on-shore or off-shore, are routinely exposed to temperature extremes,
excessive moisture and humidity from rainfall, mist, and fog. Mechanical and electrical
stressors may include vigorous, prolonged vibration, torque, damage from rodents, EMI
interference, and even lightning strikes.
• In the Mining industry, environmental conditions are extremely harsh. Dust, dirt and
dampness can threaten signal transmission equipment and performance. In some mines,
caustic chemicals and potentially explosive ambient conditions exacerbate the threat. While
the use of conduit, aerial fiber optic cabling and wireless communications can alleviate
some risk, mining remains one of the most challenging industries for industrial networking.
Untimely and costly disruptions can largely be
prevented by installation of a robust network
infrastructure utilizing environmentally
hardened, industrial-grade components in all
three OSI layers. A ruggedly designed
framework enables industrial enterprises to
carry out their mission-critical functions by
providing the highest possible levels of:
Safety. Optimum safety is critical in all
industrial operations. Full safety demands
fail-safe reliability and redundancy of data
transmissions, as well as network components
that meet and exceed industrial requirements
for potentially hazardous environments.
Uptime. Prevention of signal transmission
problems is a major factor in ensuring
consistent and dependable network uptime
and plant productivity. Whether an operation
involves a discrete manufacturing facility,
a processing plant or an infrastructure site,
Oil, gas and petrochemical plants, water and wastewater facilities, wind farms and mines are just a such as an airport or power generation plant,
few examples of industrial operations in which extreme environmental hazards can be detrimental to the keeping operations running smoothly and
performance and reliability of commercial-grade Ethernet cabling, connectivity and networking devices. reliably assures optimum uptime and
peace of mind.
Given these environmental risks, it is water and wastewater treatment facilities, Control. Continuous monitoring, management
clear that the networked communications airports and transportation hubs, military and control, as well as operational efficiency,
systems in extreme environments must be bases, ships and shipyards, railyards, tunnels, require continuity in data transmission and
exceptionally rugged and durable. Any dams and bridges. network availability. Any network failure, and
physical deterioration or electrical failure subsequent downtime, can result in severe
Networks in all of these operations must
in key data transmission components can and extremely costly consequences.
perform in extreme and often hazardous
lead to unreliable network performance
environments and every operation has its own
and/or safety issues, and may ultimately The Real Costs of Network Failure
set of environmental challenges to contend
lead to loss of critical data, costly downtime,
with. Analysts report that an overwhelming Industrial plants rely heavily on their
or even catastrophic failure.
percentage of unplanned downtime in automation, instrumentation and control
Network Safety, Uptime and industrial operations can be attributed to data communications to relay signals
Control Are Paramount network infrastructure failure. According to between devices, machinery and the control
one network management report, fully 72 system to activate events on an exacting and
‘Industry’ is a broad term encompassing percent of network faults can be attributed pre-determined schedule, with little or no
a multitude of diverse operations — from to failure at the OSI (Open Systems margin for error. Many industrial facilities
discrete manufacturing of every kind, to Interconnection) Layer 1 (Physical Media), are sizeable and their networking products
processing of foods and beverages, pulp and Layer 2 (Data Link) and/or Layer 3 (Network). must meet or exceed stringent industrial
paper, chemicals, oil/gas and petrochemicals, regulations and ratings. Users also desire
to commercial and government sites such as optimal manageability and security so
power generation plants, wind energy farms, that network availability attains 99.999%
uptime or better.
Maximum productivity with minimal Commercial-grade Components • Chemical Exposure. Oils, solvents,
downtime is a key goal, and 24/7 network Are Not the Solution chemicals and cleaning solutions can soak
performance and reliability are critical to into COTS cables, especially under heat,
In a typical office, the Ethernet
achieving that goal. No matter what the causing the cable jacket to swell and lose
infrastructure is installed in a relatively
industry, if a switch, connector or cabling mechanical strength.
clean, quiet environment with cables hidden
system in the plant fails, the cost of parts On the hardware side, corrosive chemicals
behind walls, in ceilings or under floors and
replacement and repair represents only a tiny can damage the electronics in commercial
network switches, hardware and connectivity
fraction of the overall costs associated with switches, whereas ruggedized industrial
components sheltered in protected areas.
production downtime. switches are securely sealed to prevent
Industrial facilities present a very different ingress of these substances.
For example, if a cabling system component
reality. Here, many if not most cables,
or Ethernet switch fails in a power generation • Humidity Levels of up to 99 percent
connectors, switches, and active network
facility, the repair/labor costs alone could be can be accommodated by industrial-grade
components are integral to machine
15-20 times the cost of the component itself. switches, which can also be sealed to
automation, instrumentation and control
However, disruptions in the plant’s flow of meet IP67 standards.
systems, which places them in harsh and
information or control signals could lead to
potentially hazardous situations. Even the • UV Radiation Exposure can cause
power outages — which, even today, cost the
best Commercial-Off-The-Shelf (COTS) COTS cable jackets to decompose at
power generation industry as much as $150
Ethernet systems are not made to handle such an accelerated rate, compromising
billion per year. Downtime in an automotive
conditions over time. Rugged conditions call mechanical strength and electrical
assembly plant capable of producing one
for ruggedized cables and only industrial- performance.
vehicle per minute would stand to lose profits
grade Ethernet system components are built • Physical Hazards. The factory floor
of about $2,000 to $3,000 per minute for
tough enough to withstand the hazards and holds many mechanical risks, especially
small car production, and up to $8,000 per
risks they are exposed to day after day. for machine automation cables and
minute for SUV and pick-up truck production!
Consider, for example, the deleterious effects connectors. Excessive machine movement
The indirect costs of Ethernet system failure or vibration can result in cables being
the following common environmental
in any industry must take into account lost pulled or stretched with excessive force,
conditions can have on network components:
productivity, delayed downstream processes, which can create imbalance between the
cost of system shut-down and start-up, and • Temperature Extremes. Extreme cold pairs, degrade electrical performance, and
the potentially devastating loss of service to can make COTS cables stiff and brittle, increase susceptibility to ambient EMI/RFI.
customers relying on the plant’s mission- while elevated temperatures can degrade Plant floor vehicles, such as forklifts and
critical output. Depending on the industry the plastic used in the cables’ construction moving carts, can accidentally run over
and overall operating costs, these indirect and cause an increase in attenuation. cables, causing abrasion, crushing or
effects can send total downtime costs Industrial-grade cables are available that cut-through.
soaring to hundreds of thousands, even will operate in a wider temperature range
millions of dollars. (-40°C to +85°C) than commercial cables Even well-made, properly installed COTS
(0°C to +60°C). Ethernet components are not constructed
That is why investing in a high-quality,
Commercial-grade hardware (switches, to survive these kinds of hazards. Only
rugged Ethernet infrastructure designed
etc.) is designed to operate from 0°C to hardened, industrial-grade components
specifically for use in harsh environments is a
+40°C, while industrial Ethernet hardware are robust enough to withstand the
wise business decision — one that can provide
can operate efficiently from 0°C to environmental challenges present every
tremendous peace of mind to network
+60°C — extendable to -40°C to +85°C day in industrial settings.
engineers and administrators and the
organizations they serve. (conformal coating also available for
Industrial Ethernet Hardware vs. Typical Office-grade Ethernet Hardware
(Hub / Switch / Fiber Interfaces) Industrial Ethernet Hardware Typical Office-grade Ethernet Hardware
Operating Temperature 0°C to +60°C standard, with extended temp of -40ºC to 0°C to +40°C
+85°C 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 V
being the most common/standard Internal power supply
No 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 Management
Serial (RS232) Serial (RS232)
CLI (command line interface) CLI (command line interface)
EtherNet / IP™ and PROFINET profiles for
integration 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
- 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, cUL
Class 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 (19”rack or tabletop)
Hubs Yes (DIN rail) Yes (19”rack or tabletop)
Transceiver Yes (DIN rail) Yes (19”rack or tabletop)
Firewall Yes (DIN rail) Yes (19”rack or tabletop)
“Ruggedized” for High Mean Conformal coating. A special coating • Industrial grade Cat 5e (2-pair and
Time Between Failure is applied to PCBs to protect electronic 4-pair) and Cat 6 UTP (4-pair) cables
components in damp or corrosive with heavy-duty oil- and UV-resistant
In selecting physical media, data links and
environments. jackets. Some Category cables feature a
network hardware for the industrial Ethernet,
Bonded-Pair inner construction in which
multiple factors should be considered to Redundancy. Redundant power, redundant
the conductor insulation of the pairs is
ensure optimal performance, ease of media paths and even redundant devices can
affixed along their longitudinal axis to
maintenance, and long-term reliability. assure 24/7 uptime.
ensure consistent conductor concentricity
Ruggedized industrial Ethernet products have Bandwidth. With an ever-increasing number to prevent any performance-robbing
been designed specifically to network in tough of Ethernet-enabled devices being added to gaps between the conductor pairs during
environments, to support the industrial networks, sufficient bandwidth is needed to installation and use.
protocols which are being transmitted across ensure meeting future needs. • Upjacketed and armored cables for more
these networks, and to accommodate the extreme environments.
environmental rigors of the location. Key Hardened Components Protect
considerations in specifying industrial-grade Network Integrity • Continuous flex cables designed for
network components include: use with continuous motion machines
As stated previously, an overwhelming and automation systems.
MTBF (Mean Time Between Failure). percentage of network performance problems
• Low smoke zero halogen (LSZH)
Industrial Ethernet products are designed to are due to failure at OSI Layer 1, Layer 2 or
cables, waterblocked and burial cables
provide the same lifespan as other automation Layer 3. Therefore, it is critical to ensure that
are also available.
components — typically 10 to 30 years or components at all three layers — physical
more. By comparison, typical commercial- media, data links and active network devices • Cables designed for use with leading
grade products are built to achieve a 5-year — are designed and constructed to withstand industrial automation networking and
average lifespan. the operational and environmental stressors communications protocols, such as
to which they are subjected. For each category, EtherNet/IP (ODVA), Modbus TCP/IP,
Mounting options. Industrial Ethernet ProfiNet and Fieldbus HSE.
multiple factors need to be considered to
hardware devices are usually DIN rail mounted
ensure optimal performance, ease of • Industrial-grade connectivity components,
or bolted directly onto the machines that
maintenance, and long-term reliability of such as: IP67- or IP20-rated UTP or FTP
receive transmitted data.
the mission-critical network. patch cords, connectors, modular jacks and
Small form factor. Equipment is typically plug kits, adaptors, faceplates and surface
designed to occupy less space to allow greater Physical Media — mount boxes.
density within a control panel. Cabling & Connectivity
Ventilation without fans. Industrial Ethernet For the physical media layer, there are a host
devices rely on passive heat dissipation. of products in today’s marketplace that fully
conform to the Ethernet LAN.IEEE 802.3
Protection class. Devices must be available standard. Selection will depend on each
in dustproof and waterproof housings. plant’s network configuration and application
requirements. Products include:
• Heavy-duty, all dielectric, indoor/
outdoor-rated optical fiber cabling
in single-mode and multimode
constructions. Many feature water-
blocking agents for added protection
in moisture-laden environments.
Industrial Ethernet Cable Selection
Fiber optic Ethernet cables represent twisted pair cables are available using • Insulations: Most industrial-grade
the ultimate in future-proofing and are any number of conductor types, Ethernet cables utilize a polyolefin
available for indoor use (riser or tray) insulations, shielding and jackets . insulation . For extreme temperatures,
or outdoor use (including direct burial) . Armoring is also available for extremely however, an FEP insulation (and
Typical designs use multimode fibers harsh environments . jacket) is recommended .
in a loose tube configuration, usually
Construction selection criteria: • Jackets: Oil- and sunlight-resistant
available in 2- to 72-fiber constructions .
cables typically have a PVC jacket .
For plenums, tight buffered, 2- or 6-fiber • Unshielded or shielded?
If the cables are exposed to moisture,
single-mode or multimode construc- Unshielded products can be used
a waterblocking agent should be
tions are typically available . in most environments; shielded
part of the cable’s construction, as
products are recommended for
• To handle Gigabit Ethernet light well as inner and outer PE jackets if
especially high noise environments .
sources and any expanded bandwidth the cable is buried . Gas-resistance
requirements some cables use a • Shields: Typically a foil or braid calls for an FEP-jacketed cable, while
laser-optimized fiber . is used to protect the integrity low smoke zero halogen (LSZH) PVC
of the signal and to screen out jackets are available for environments
• For moisture protection, a water-
any undesirable interference or where smoke/flames are a risk . For
blocking agent should be included
noise . However, to provide extra extreme temperature environments,
in the cable’s construction .
durability and noise protection, a the cables should feature an FEP
• In particularly harsh environments, foil/braid combination can be used . jacket (for an extended operating
a CPE outer jacket will provide addi- temperature of -70ºC to +150ºC) .
• Solid or stranded conductors? Solid And, for continuous flexing or robotic
tional protection against chemicals or
conductors are appropriate for most applications (which could include
abrasion; an armor tape or aluminum/
installations; stranded conductors the complication of weld splatter),
steel armoring may also be appropri-
provide extra flexibility for better cables with TPE inner and outer
ate for the extreme environments,
handling in close environments . For jackets are recommended .
including some burial situations .
robotic/continuous flex applications,
• Ratings include: UL Type: OFNR, use of a cable with a highly stranded
cUL Type: OFN FT4, IEEE 383-2003 conductor is recommended .
Flame Test .
• Pair conformity/centricity:
Copper Ethernet cables are the Bonded-Pair cables provide resis-
more traditional option in industrial tance to the rigors of installation by
installations, available for either Cat- utilizing a manufacturing technique
egory 5e or Category 6 applications . that affixes the insulation of the cable
Category 5e cables are the dominant pairs along their longitudinal axes
choice today, while Category 6 cables so no gaps can develop between the
are finding increasing use where Giga- conductor pairs; a nonbonded-pair
bit speeds and increased bandwidth cable construction can be susceptible
are desired and/or for future-proofing to pair-gapping during installation
purposes . Category 5e and Category 6 (and impedance mismatches) .
The Proof is in the Testing Cold Bend. Conducted per UL 444, samples of Cold Impact. In this test, also conducted
cables were left in a controlled temperature per UL 444, an aluminum weight was
A series of rigorous tests conducted by Belden
and humidity chamber called a cold box. They dropped down a hollow guide-tube to smash
on COTS cables versus industrial-grade cables
remained for one hour prior to testing. They against a segment of cable under test. The
has proven that the COTS cables simply do not
were then tested (at -80°C, -60°C, and -40°C) impact force delivered 24 in-lbs or 2.7 joules
stand up as well as industrial-grade Ethernet
by being partially wound around a 3-inch of impact energy. Each length of cable
cables in harsh environments. All nine tests
diameter horizontal mandrel with one end of had been previously cooled; and a total of
were performed on state-of-the-art testing
the cable under tension from an aluminum ten samples were inspected at a series of
equipment, and all the cables used in the
weight. The cables were then unrolled and increasingly lower temperatures to determine
study initially tested as fully compliant to
visually inspected to check for cracks in the if the cables’ jacket integrity was damaged,
ANSI/TIA/EIA 568-B.2 Cat 5e standards.
jacket. The COTS cable became brittle and a condition which could allow ingress of
Following is a summary of tests performed
showed visible cracks. The industrial-grade chemicals and moisture and could potential
and the results:
high/low temp cable had no visible damage. lead to a conductor-to-conductor short
Abrasion. Using a fixed drum covered with or even catastrophic failure. The standard
sandpaper, cables were stretched across a jacketed COTS cables failed at -20°C. The
portion of its circumference, then moved back industrial-grade cables, protected by
and forth cyclically for 25 cycle counts. At high-low temperature jackets, did not
that point, the conductors of the COTS cable crack until impacted at -70°C.
could be seen through breaks in the jacket,
which would cause it to lose mechanical and
electrical integrity. The pairs of the armored
industrial cable were not compromised.
In the cold bend test, the cables were first
placed into a cold box.
In the cold impact test, after the cable is cooled
an aluminum weight smashes against it.
The test set-up — with the cables on a fixed drum
covered with sandpaper.
After the cold box, the cables were partially wound
around a mandrel and subjected to the tension
experienced through the use of an aluminum weight.
Commercial cable after 25 cycles.
Industrial cable after 25 cycles.
Crushing. In this test, an Instron machine Cut-Through. In this test, based on CSA High Temperature. In this test, three spools
head brings a 2-inch by 2-inch plate down standard #22.2, a chisel-point mandrel on an of cable were suspended from a mandrel in a
on a segment of cable to crush it — with Instron machine was lowered onto a segment high-temperature oven. The blue cable in the
failure defined as the point at which the of cable to test the cable’s susceptibility to a middle is a COTS Cat 5e cable with standard
cable would no longer reliably support cut-through leaving the conductor exposed. PVC jacket. The other two are black industrial-
Cat 5e performance. Each cable’s electrical Several kinds of cable were sliced by the grade Cat 5e cables, one with a PVC jacket,
characteristics were measured throughout chisel to the point where a short circuit the other jacketed in FEP. All cables were first
the testing. At 400 lbs applied force, the was sensed across the conductors, creating tested at an ambient temperature of 20°C and
COTS cable with PVC jacket failed — it was a potentially hazardous situation. The COTS were then tested again after being exposed
smashed flat and would not spring back to cable shorted out at 92 lbs of applied force. to a high temperature of 60°C over time. The
its original shape. The industrial-grade, Two unarmored industrial-grade cables COTS cable functioned acceptably at 20°C
black-jacketed armored cable had a took 205 lbs and 346 lbs of applied force to but, over time, at 60°C, attenuation increased
failure value of 2,250 lbs — over a ton. short. The armored industrial cable took to where the cable would not support a run
346 lbs applied force to pierce the armor; distance of 100 meters. The industrial-grade
however, the conductors did not short until cables, even after exposure to 60°C over
a force of 1,048 lbs was applied. time, continued to support the maximum
The Instron crushing device. A chisel-point mandrel on an Instron machine The cables were tested, as suspended,
performs the cut-through procedure. in a high temp oven.
COTS vs 7928A vs 7922A Cat 5e
Attenuation at 20°C and 60°C
The COTS cable is smashed flat and fails at 400 lbs.
0 10 20 30 40 50 60 70 80 90 100
The industrial-grade cable showed
little attenuation — even at 60°C.
The industrial-grade armored cable fails only after a
ton of crush pressure.
Oil Resistance. In this test, conducted per UV Exposure. In this procedure-based Water Immersion. In this test, the
UL 1277, lengths of cable were immersed ASTM G 154 test (Standard Practices for electrical properties of the cables (primarily
in containers of oil, which in turn were Operating Fluorescent Light Apparatus for attenuation) were measured initially. Then
immersed in a water bath that was placed in UV Exposure of Non-Metallic Materials), the cables were coiled into a dry container,
a chamber held at 125°C for 60 days. After segments of various cables were affixed and water was added to submerge them.
the test period, cable segments were removed to panels that were mounted so that the The cables were tested intermittently over
and their jackets evaluated for tensile and cables directly faced a fluorescent light a six-month period. The COTS cable showed
elongation properties. Exposure to oil and source whose output range was adjusted increased attenuation as soon as the cable
lubricants can make jacketing brittle and to match that of solar radiation levels. The was immersed in water and this continued to
fragile, even at room temperature, resulting cables were exposed to light for 720 hours degrade over the half-year immersion. After
in loss of mechanical properties and reduced (30 days), then their jackets were visually six months of immersion, the industrial-
service life. The blue COTS cable showed signs checked for discoloration, as well as for grade cable showed only a slight increase
of this type of deterioration. The industrial signs of degradation in tensile strength in attenuation — and the cable still
cable’s jacket did not, because the and elongation. The COTS cable was not exceeded the Cat 5e requirements.
materials and jacket thickness are rated sunlight-resistant and their jackets showed
for exposure to oil and other substances, discoloration, a precursor to degradation of
even at elevated temperatures. the jacket material. The industrial-grade
cables were rated to resist the effects of
sunlight and other UV sources and showed
no jacket damage.
The oil bath test, conducted as specified The UV exposure test is based upon The water bath test is a six-month long test,
in UL 1277. ASTM procedures. with the cables fully submerged in water.
Ethernet Switch Selection Options
Wireless or Wired? Panel Mount: A variety of switches
and wireless Ethernet devices are
While wireless has its advantages
available, some with adapters for
in industrial applications, it is poorly
panel mounting . Some companies
suited for transmitting time-sensitive
offer ultra-rugged switch options for
control data that could adversely
use in extreme environments .
affect productivity or safety .
IP67 Ethernet Connectors?
Pros: Provides mobility and network
flexibility . Limited cabling costs . IP67-rated connectors are ideal
Overall convenience . for use in extremely damp/wet
environments and applications where This Hirschmann OCTOPUS switch is ideal
Cons: Not as reliable or as secure for installation in vibration-prone environments.
significant vibration could result in Here, the Ethernet IP67 switch is used to provide
as a cabled solution . Larger and more
intermittent communication from passenger compartment video surveillance, as
complex networks require a site survey .
connector contact deterioration . The well as travel updates and entertainment.
Achieving long distance communica-
connector, approved by the ODVA
tions reliably can be very difficult .
(Open Device Vendor Association), is Managed or Unmanaged Switches?
Wired the M12 D-code Ethernet connector —
a 4-pin connector that uses CAT 5e or A classic analogy for management
Pros: Significantly more reliable and better (2-pair) . has always been the dashboard and
secure . Far higher data speeds are electronics of a car:
possible — up to 10 Gigabit with some
wired switches . 3 4 Pin Function A managed switch is akin to a car with
1 TD + Transmit Data + a dashboard and an unmanaged switch
Cons: Lower flexibility . High initial cost 2 RD + Receive Data +
is one without . A managed switch can,
3 TD - Transmit Data -
of cabling and the cost of relocating an 4 RD - Receive Data - through web browser access (secured
Ethernet device (if it will not be close 2 1 Housing: shield by password), control certain internal
to a network connection/port) . switch functionality that may be criti-
cal to the flow of data and the function
The IP67/waterproof connector of the network . A managed switch also
DIN Rail, 19" Rack or Panel Mounted? solution is typically available as field- has the ability to inform and react to
installable connectors or pre-terminated certain conditions and provide a level
The mounting choice/preference will
and overmolded patch cords (single of security, making it an ideal solution
dictate which products are applicable .
M12 or RJ45 or double ended M12-M12, for an application with a higher need for
DIN Rail Mount: Managed and M12-RJ45 and RJ45-RJ45) . A bulkhead uptime (where control data, rather than
unmanaged open rail switches, M12 is an excellent solution for migrat- measurement data is transmitted) .
unmanaged switches, and wireless ing the Ethernet cable from the inside
An unmanaged switch has none
Ethernet devices . of the control panel to the outside .
of this functionality and is typically a
Rack Mount: Some suppliers offer a Keep in mind that the IP67 rating is plug-and-play switch and is best used
DIN rail adapter for 19" racks, permit- not always used in wet environments or on smaller stand-alone applications or
ting multiple DIN rail mount devices to applications where vibration is an issue: as an edge-switch in a larger network .
be mounted inside a 19" rack . Some users choose instead to deploy
all M12 D-code connectors so that they
can eliminate control panels .
Hardware: Switches, Active Network • Ring Topology. In a ring configuration, • Mesh Topology. Mesh topologies
Devices and Accessories the easier and simpler of the two types, require that all switches in the mesh
a series of managed switches are daisy- support STP (Spanning Tree Protocol)
A wide range of hardware is available to
chained and the first and last switch of or RSTP (Rapid Spanning Tree Protocol).
enable management of industrial Ethernet
the chain are then linked to form a ring. While supported by most managed
networks at the information, control and
In the event of a failure in the media or switches, this feature can be difficult
device levels. There are products to support
any of the switches, data is automatically to configure and network recovery can
both copper and optical fiber media, as well
re-routed, achieving network resiliency be several seconds — depending on the
as switches capable of data speeds as high as
in milliseconds. number of switches in the mesh and
10 Gigabits per second. At a minimum, all
how the fail-over is configured.
of these network components — switches,
connectors, and other hardware — should
offer robust construction and resistance to
high temperatures, vibration and EMI.
Industrial Ethernet Hardware Standards and Specifications
The Importance of Redundancy
Temperature and Humidity/Moisture cUL 1604 — the standard for Class 1,
Another Ethernet factor considered to be Division 2, hazardous locations
an industry best practice for mission-critical Typical industrial temperature range
is 0° to +60°C IEC 61850-3 — the standard for electrical
applications is redundancy, which is extremely
substation automation networks
important but sometimes overlooked in Extended temperature range
selecting industrial Ethernet switches. Two components are available from IEEE 1613 — the standard for
specific kinds of redundancy are key -40° up to +85°C communications networking devices
to maintaining uninterrupted signal in electrical substations
IP20/IP30/IP67 (95% relative humidity,
transmission and maximum uptime. non-condensing — not applicable EN50155 — European specification for
to IP67 onboard rolling stock/train applications
Power source redundancy. Having an
uninterruptible power source (UPS) is IP classifications are governed by EN50121-4 — European specification
absolutely critical to consistent and reliable the IEC 429 standard for track-side rail applications
switch performance. Specifying switches that
Mechanical Stability NEMA TS-2 — US-based standard for
have dual power input capabilities means traffic signaling and communications
that if one power source fails, the other Shock and vibration tests should
immediately takes over. be in accordance with PLC standards ATEX100A, ZONE 2 — a standard
IEC 1131-2, EC 60068 required in Europe for hazardous/
Data path redundancy. The daisy-chain explosive environments (similar to,
network topologies used by many industrial but not compatible with cUL 1604
plants to connect automated machinery and EMI: EN 50022-2, FCC part15 (class B) Class 1, Div 2)
devices have one inherent flaw: if any link GL (Germanischer Lloyd) — a German
IEC 1000-4-2, IEC 1000-4-6,
between the two switches fails, the entire standard that has gained global accep-
IEC 1000-4-4, EN 61000
system could potentially go down, as the tance for marine (ship, offshore oil, etc .),
devices on one network segment can no Certifications some petroleum and wind industries
longer communicate with devices in other cUL 508 — the basic and most
segments. The solution is to build in a common safety standard for industrial
redundant data path which can take the control equipment
form of either a ring or mesh topology.