Who Puts the 'Industrial’ in Ethernet?
Industrial Ethernet hardware can take plant-floor punishment without pampering in enclosures, allowing shorter cable runs with simpler distributed (rather than centralized) designs, and higher reliability than commercial-level Ethernet switches, routers, hubs, gateways, and connectors. Industrial ratings (such as NEMA 4x or IP67 and beyond) applied to Ethernet hardware mean that equipment can h...
Mark T. Hoske, Control Engineering
Industrial Ethernet hardware can take plant-floor punishment without pampering in enclosures, allowing shorter cable runs with simpler distributed (rather than centralized) designs, and higher reliability than commercial-level Ethernet switches, routers, hubs, gateways, and connectors. Industrial ratings (such as NEMA 4x or IP67 and beyond) applied to Ethernet hardware mean that equipment can handle temperature extremes (as much as -40 to 85 °C), and even liquid and dust, and maintain reliable performance for years instead of months.
If commercial Ethernet devices are reliably enclosed and cooled, that might be enough to preserve reliability. Beyond that, higher costs for industrial design will cut down on mean time between failures, possibly preventing a process interruption or data loss. It all depends on the application. Cisco Systems Inc., for instance, while well-known in various network application spaces, is among companies that realize that industrial environments pose rugged challenges. Cisco forged agreements with Honeywell and Rockwell Automation, who have greater understanding of customer needs in process and discrete manufacturing operations.
Enclosures can work wonders, admits Tom Edwards, senior technical advisor, Opto 22. Edwards contends that installation is mainly “what makes Ethernet hardware suitable for industrial environments…. Most of the off-the-shelf equipment is perfectly suitable for industrial installation if it can be protected from the normal bumps and scrapes ... in these types of settings. Most of the extra cost of 'industrial’ equipment is the packaging added to keep it from being damaged and to makeit fit in a 19-in. rack.”
To make an Ethernet device industrial, says Greg Paukert, product manager, Tyco Electronics, using impact resistant plastics and rubber materials “seals against many chemicals including water to give the product a 10- to 20-year performance life.” Connectors that use a positive locking coupling system ensure the interconnection is “fully-engaged and properly mated,” Paukert adds.
When people think of industrial grade, they think of hardware that can operate under the harshest conditions, says Chris Harris, communications product manager, AutomationDirect. Various standards apply to making Ethernet industrial.
“Industrial hardware is expected to operate properly even when subjected to extreme temperatures, power surges (IEEE-472), extreme vibration (IEC 68-2-6), and when in hazardous locations [UL 1604, CSA C22.2/213 (Class 1, Div. 2)],” Harris says.
Design differences, says Eddie Lee, national product sales manager, Moxa Technologies Inc., mean that “specifications of industrial Ethernet switches usually are two to three times stronger than the ratings found in comparable office grade equipment.” The Class 1, Div. 2 rating for industrial Ethernet switches allows operation in hazardous locations where combustible gases or particles may be present, Lee says, such as in oil and gas, semiconductor, pulp and paper, and other markets.
How often a switch is exposed also makes a difference, says, Richard Hutton, automation product manager, Schneider Electric North America. “If a switch or cable is being accessed frequently, a more rugged connection point or device is required.”
Skip Hansen, I/O systems product manager, Beckhoff Automation, explains that a “noisy environment may be one with welders, variable frequency drives (VFDs) and induction heaters. The switches used should have the ability to be mounted in a control cabinet or stand alone. In the case of stand-alone, switches certified to the IP67 protection class should be considered.”
Other contributors to industrial electrical noise include solenoids, motors, and motion controls, says Larry Komarek, Phoenix Contact automation product manager, Americas Business Unit. “Industrial Ethernet devices designed to the IEC 61000-4 series of specifications have two to three times higher electrical noise immunity than commercial devices, which are typically designed to the EN 55024 and 50082-1 specifications,” Komarek says. Paukert from Tyco says expects more use of “shielded, plated plastic receptacles for >20dB down shield effectiveness.”
Whether network devices are distributed and exposed, or centralized and enclosed, “commercial off-the-shelf (COTS) Ethernet cabling and connectivity are not tough enough to withstand these stressors and continue to deliver the signal transmission performance required for automation and control networks,” says Frank Koditek, Belden industrial market manager. Within a plant, Koditek warns, networking components, as well as their cables, may be exposed to temperature extremes, sunlight, solvents, oils, moisture, and chemicals.
They’re also subject to mechanical stresses on cables from excessive pulling, and the risk of abrasion, crushing or cut-through resulting from plant floor activities. Category 6 or 5e Ethernet cables avoid “classic network failure scenarios, from incremental damage and performance degradation, to intermittent operation, to catastrophic failure,” Koditek says.
Connectors, network failures
Connectors matter, as well. Ed Nabrotzky, general manager, industrial communication, Woodhead Industries, says, “Almost 70% of network failures happen because of a mechanical failure involving the cabling and connectors. Things can be jarred loose, worn out, improperly installed after a shut down, or even severed after being driven over by a forklift. Commercial grade cables and plastic connectors simply aren’t made to withstand the abuse present on the factory floor.” Special materials and design techniques create rugged products that can survive industrial conditions, Nabrotzky says.
Some off-the-shelf RJ45 connectors perform adequately when tested against the recognized shock and vibration specifications; others do not, says Brian Oulton, marketing manager, Logix/NetLinx Business, Rockwell Automation. “Many industrial Ethernet standards also recognize IP65 and IP67 environmentally sealed connectors (for example, M12) that are effective in many industrial applications,” Oulton says.
Tougher protocols inside
In addition to hardened devices, cables, and connectors, plant-floor applications also can require industrial protocols running over Ethernet physical layer.
Choice of protocols “depends on the nature of the automation equipment in a particular location,” says Brian Tutor, product manager for Lantronix, “however the most commonly utilized protocols in industrial environments are Modbus TCP, EtherNet/IP, and Profinet. ( Control Engineering provided research on Industrial Ethernet protocol usage in the December 2006 issue.) “Typical rugged characteristics of Ethernet protocols include: wide temperature (-40 to 70 °C), high shock and vibration tested, electric isolation and FM Class 1, Div. 2 approval for hazardous locations,” Tutor says.
Rockwell’s Oulton suggests that industrial Ethernet protocols and connected products should contain appropriate error checking and diagnostics to take action if communications is in-error or interrupted. “For example, many protocols contain checksums and appropriate acknowledgement to ensure timely and reliable data delivery, and many I/O products are designed to move to a user-selected value if communications stops,” Oulton says.
Switched Ethernet cuts collisions
Today’s switched Ethernet has moved past prior issues with communications reliability and performance, according to Paul Wacker, product manager, Advantech Inc. “Network contention issues (called collisions) have virtually been eliminated with the use of Ethernet switches, which intelligently forward messages from one device to another, ensuring deterministic performance,” Wacker says. “Magnetic coupling and differential signaling utilized by 10/100 Base-TX Ethernet reduces communications disturbances caused by differences in ground potential between devices and external EMI/RFI sources. For additional levels of protection, fiber optic cable should be used.”
Schneider Electric’s Hutton likes industrial Ethernet hardware designs that incorporate added security or redundancy measures to keep a system up and running, such as the use of rapid spanning tree functionality, individual IP address filtering and the use of fiber optic dual cabling.
Because industrial Ethernet is rapidly becoming the primary real-time network within and between automation control systems, Phoenix Contact’s Komarek says, network infrastructure products often are supported by the plant floor personnel who support the control systems. “Software configuration interfaces, wiring and mounting arrangements must be similar to the PLC/PC-based control systems they are supporting,” Komarek says. “In IT-based systems, software configurations are made in DOS-like text screens. Industrial options such as memory modules, diagnostic displays, etc., allow installation by plant personnel without access to laptops. IT devices rely on a central supervisory console to diagnose system status.”
Self-serve design is an advantage, adds Hutton, when “industrial Ethernet systems are being designed for minimal upkeep with simple tools and interface methods like Web browser views for data and configuration. Plant maintenance personnel can maintain and monitor the system themselves, rather than waiting for an IT professional for assistance.”
Mounting expediency is another reason to go industrial, says Moxa’s Lee. Industrial Ethernet switches are often housed in rugged metal enclosures using DIN-rail or panel mounting options, he says, while most commercial switches cannot mount conveniently inside control panels without the inefficiencies of building a shelf and strapping the unit in place. Also, Lee adds, industrial grade equipment often has an alarm contact, which could help avoid or minimize downtime.
Capital versus lifecycle costs
Sometimes people select commercial products because of lower capital costs. Lifecycle costs can make an industrial design worth the investment when environmental factors cause more frequent replacement of commercial products.
Companies with capital cost constraints no longer have to choose lower-cost commercial products that are less rugged, suggests Larry Winchester, business development manager, Ethernet Direct. “Many companies are using commercial switches or unmanaged industrial switches due the high price of industrial managed switches. Ethernet Direct has lowered the cost of Industrial Ethernet products up to 40% compared to other industrial brands without sacrificing quality, reliability, and performance,” Winchester says, by automating comparison, selection, quotation, and ordering. Online support and extensive industrial Ethernet reference libraries provide a high level of support, he adds.
Additional products, contacts, and resources follow at bottom.
Mark T. Hoske, editor in chief of Control Engineering , can be reached at MHoske@cfemedia.com .
Industrial Ethernet: Switches, hubs, gateways
Industrially hardened Ethernet products abound, and numerous technical papers and spec sheets describe essential attributes. In addition to the resources listed here, find more linked to this article at
8x industrial hub
AC808 Ethernet hub from B&R Industrial Automation Corp. can be used as a Level 2 hub in standard Ethernet or real-time industrial Ethernet Powerlink networks. It is suitable for 100 MBit/s (Fast Ethernet) and 10 MBit/s networks. The hub automatically recognizes the correct transfer speed and configures the respective channels to it. It uses RJ45 connectors. Pin assignments can be crossed for the first channel using a switch, so the same type of cable can be used for a connection between hubs (hub-hub) as is used between the hub and a network station. Mounting is horizontal or vertical on the rail or direct mounting on the sides. B&R Industrial Automation
Troubleshoot Ethernet, study online
Contemporary Controls’ technical guide, “The ABCs of Ethernet Troubleshooting,” asks 22 common questions to consider when troubleshooting a network at Contemporary Controls
900 MHz Ethernet modem
Dataradio offers the HiPR-900 FHSS IP/Ethernet Modem, which operates 902-928 MHz. It’s a high speed, license-free industrial IP/Ethernet that brings a secure user data over an Ethernet or serial connection onto an IP based network. Patent-pending Dataradio Parallel Decode technology combines spatial diversity and smart combining to give it increased sensitivity and immunity to multipath, producing a more reliable radio link. Dataradio
More switch bandwidth, secure software
GarrettCom Magnum Line 6k25e offers roughly 8 times the bandwidth capability of previous Magnum 6K switches and is configurable, important for the power utility industry, industrial applications, and security. DynaStar OS 7.4 software extends the reach of the newer generation carrier data services that are based on MPLS (MultiProtocol Label Switching) to power utility substations and other distributed industrial sites. The software extends secure, prioritized management of critical SCADA traffic to MPLS-based services, enabling a common SCADA network with video surveillance, remote provisioning, and other applications. GarrettCom Inc.
Rugged, fast Ethernet switches
With a -40 to 85 °C (-40 to 185 °F) operating range, Uber Rugged Mach1000 Ethernet switches extend Hirschmann’s industrial Ethernet product portfolio, taking it beyond the realm of factory and process automation into traffic management and surveillance, electrical power generation and distribution, and a variety of other demanding and mission-critical applications. The new 19-in. rack-mount switches offer modular design with up to 26 ports (24 of these are up to 100 megabit and 2 are Gigabit). Modularity of these switches provides users choice of RJ45 and fiber ports in multimode, single mode and long-haul with a variety of fiber connector options. They are ideal for high temperatures and RFI/EMI noise and meet NEMA TS-2, IEEE 1613, and IEC 61850-3 requirements. Hirschmann
Gigabit industrial Ethernet switches
N-Tron’s 7000 Series, Gigabit capable Industrial Ethernet Switches connect Ethernet enabled industrial and/or security equipment. They are fully managed and come standard with IGMP snooping, VLAN, QoS, trunking, mirroring, RSTP, DHCP, SNMP and Web browser management, and N-View OPC Monitoring. They are suited for use as a fiber optic ring manager, providing expanded ring size capacity, detailed fault diagnostics, and a ring healing time of approximately 30 ms. N-Tron
EtherNet/IP to serial ASCII gateway
ProSoft Technology’s EtherNet/IP to ASCII Generic Serial Gateway features one Ethernet port and up to four configurable serial ports. Each port is capable of supporting an ASCII network. It can be used for multiple devices, such as barcode readers, scanners, scales, printers, or terminals. ProSoft Technology
Industrial Ethernet security modules
Protect the plant floor from data manipulation, espionage, unauthorized access, and automated intrusions using the Scalance S family of industrial Ethernet security modules from Siemens Energy & Automation Inc. They offer functionality and protection of a firewall and virtual private network (VPN), allowing only real-time, authenticated communication between authorized devices within the automation network. A software security client offers setup from a desktop or laptop. Losses from poor plant network security will continue to be a primary concern for plant engineers and front office executives, the company says. Siemens Energy & Automation
Ethernet 10/100 MBit/s starter kit
Wago offers the Ethernet StarterKit 2, which includes a fieldbus controller for Ethernet TCP / IP 10 / 100 MBit/s and other basic components. Digital input, digital output terminals (8 each), a bus termination terminal, power supply unit (24 V dc), software, and DVD tools and documentation are included. Wago
Industrial Ethernet expands networking globally
Industrial technologies are helping expand the world’s $1.7 billion industrial wireline networking infrastructure market, according to a Venture Development Corp. (VDC) research study. “Industrial Networking Global Market Intelligence Service” projects the global market for network infrastructure products shipped for use in industrial facilities will increase at almost a 25% compound annual growth rate (CAGR) through 2011.
Of three regions in the research (Asia-Pacific; Europe, Middle East, Africa; and the Americas), the highest overall market growth rate through 2011 is forecast for Asia-Pacific. In the markets studied, much of this investment is being directed toward Ethernet-based networking products.
Industrial network shipments to Asia-Pacific markets were $298 million in 2006. Of that total, 76% were products for Ethernet networks, and the Ethernet share is forecast to increase to over 81% of a $1 billion market in 2011. These are the highest Ethernet shares among the three regions. Bus and network use in the other two regions is more established and harder to displace, though Ethernet shares there also are expected to increase, VDC says.
Direct connection: SmartMotor to Ethernet
The Animatics Corp. SmartMotor serves as a programmable motion module used in diverse automation applications, from in the ocean to outerspace. To make it easier for machine builders, the servo motor integrates a drive with precise, computer controlled motion, independent programmability, low cost, and compact form factor to eliminate control cabinets. External requirements are limited to power and a network connection.
When Animatics SmartMotor required Ethernet communications, engineers found generally available hardware and software solutions were too bulky, complicated, and expensive. And while Ethernet cards that plug into a PC appear simple, they relegate most functionality to the PC. For this embedded system, the company wanted a stand-alone technology with multiple integrated circuits and significant printed circuit board space, within limited space and budget.
Animatics integrated the Lantronix XPort embedded networking module. XPort provides networking processor hardware and software for Ethernet network Internet connections in a compact, integrated package (full photo, p. 40), with very little development time, which reduced costs and rescued tens of thousands of dollars in otherwise lost sales, with faster time to market.
To integrate the module, Animatics: 1) attached the XPort to the back of the motor, 2) connected it to the logic power and to the universal asynchronous receiver transmitter (UART) pins of the SmartMotor CPU, 3) incorporated software drivers, provided by Lantronix, into its PC resident terminal software. Initially, Animatics did not require the SmartMotor to host a website, but with the XPort’s built-in Web server, the feature proved interesting and valuable for users.
In applications, several motors can coordinate functions on an Ethernet network, allowing Ethernet messages to cause motion or I/O changes or activate pre-programmed algorithms in the motor. Alternately, the one motor also could report data to an upstream monitoring station via XPort, while communicating with other motors via a different network.
Later addition of Modbus added functionality without cost or development time.
By using Lantronix, Animatics can focus on developing integrated servos, rather than networks.