Automation MES Network Readiness

CONTENTS

Network Performance— Cabling Infrastructure

Tactical Brief

Sponsored by

02. Is Your Network Backbone Future Ready

03. Network Design Fundamentals for the Connected World

07. Down to the Wire—Building a Resilient Network Infrastructure

13. Manufacturing Trends and the MES Connection

15. Cat5E Beats Cat6 for Industrial Applications

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Is Your Network Backbone Future Ready

We don’t get to choose the body we’re born with, but we do get to choose how we take care of it. And it’s been well-established that preventative care can help ward off chronic diseases that account for 86 percent of the nation’s health spending.

This isn’t a public service message, but rather a point about how making smart decisions today can help avoid problems down the road. Much like investing in a new roof on your home today can help prevent costly leaks and major structural damage in the years to come, or regular oil changes can avert engine damage and keep cars running longer.

The same goes for the physical network fabric, but with an important advantage. Unlike the bodies we’re born with, we sometimes get to choose the network fabric used in our facilities.

This is especially pertinent if you’re like many other manufacturers today and in the process of planning to deploy a new industrial Ethernet infrastructure that seeks to harness the power of deeper insights and greater connectivity available from innovations such as The Internet of Things. Deploying a robust network infrastructure without an eye for the future will catch up with you – and cost you – in due time.

Consider the bandwidth of your network fabric. You may have capacity to meet today’s requirements, but will it be sufficient in three to five years as new bandwidth demands arise, such as with the expanding use of video capabilities?

Also, remember that network equipment can turn over as much as

four to five times compared to the physical infrastructure itself. Switches may be replaced every four years, while cabling is only replaced about every 20 years. With this in mind, it often makes more sense to put in higher-bandwidth cabling that allows the network to scale up as demands require. Today, that would require using at least 1 GB cabling.

Similar thinking should be applied to the number of ports used when designing your system. As ODVA recommends in its “Media Planning and Installation Manual,” designing a system with 20 percent or more excess ports for future expansion is a good rule of thumb. It also recommends marking those excess ports as control ports for future expansion to keep maintenance personnel informed of the ports’ purpose.

Beyond meeting future expansion needs, thoughtful considerations made during the planning and design stages can also be just as relevant for your network fabric’s day-to-day operations. For example, understanding the range of environmental conditions your physical infrastructure will be operating in will help you select the right materials or appropriate design approaches to help avoid equipment failures and subsequent downtime events.

Much like your car, your home and even your body, good decisions today translate to a better-performing and more reliable network fabric for the long haul. Additionally, reducing day-to-day uncertainty about your network’s performance can even mean less stress for you – which they say is good for your long-term health.

By Ryan Lepp




The benefits of converging industrial and information networks with a validated secure architecture based on standard Internet

Protocol (IP) technologies are well established. The benefits include greater connectivity and integration across plants, easier data sharing across the enterprise, and better visibility into real-time operations.

Bringing together information technology (IT) and operations technology (OT) networks is complex because of the gray area between IT and OT roles and responsibilities within the company. IT and OT professionals must have a common understanding of a host of techniques and technologies to overcome this complexity and establish a converged infrastructure that is secure and manageable by all critical stakeholders.

The techniques and technologies used in network design can be simplified by leveraging the ISA/IEC-62443 Zones and Conduits Model developed by the ISA99 committee. The three design areas are:

• cell or area zone• production site operations• enterprise zone integration

Designing for the cell or area zoneSeveral considerations must be made to ensure the network

infrastructure addresses your data, security, and availability requirements at the cell or area network level. Machines and

process skids are seeing high growth in number and criticality of IP connections. One of those considerations should be logical segmentation, which is the process of dividing end points into subnets and virtual local area networks (VLANs). A key recommendation for industrial networks is to create smaller layer 2 networks to improve performance with the maximum of 200 devices within a zone or VLAN.

VLAN spanning multiple switchesSegmentation allows for smaller layer 2 domains, which helps

constrain broadcast and multicast traffic. It also helps manage the network’s real-time communication properties and supports the network’s traffic-flow requirements. With segmentation, manufacturers and industrial operators can meet their security requirements by limiting remote expert or original equipment manufacturer network access to only specified machines.

Organizations often accomplish physical segmentation within the cell/area zone network by using separate cabling and switches. This common approach in Ethernet networks can become a hindrance to network performance if not properly planned. For example, physically separating input/output (I/O) and human-machine interface traffic without connecting the I/O traffic to an interconnected layer 3 switch can limit overall connectivity and even

Network Design Fundamentals for the Connected WorldBy Dan McGrath, P.E




Accelerate Deployments While Reducing Risks

The Panduit Integrated Network Zone System enables network com-munications between the control room and manufacturing floor with-in an industrial facility. Integrated with an Allen-Bradley Stratix switch, the pre-engineered, tested and vali-dated system reduces deployment time up to 75%.

ContinuedNetwork Design Fundamentals for the Connected World

cause delays. Networks should, at a minimum, be connected to a layer 2 or layer 3 switch, rather than a controller, to interconnect.

VLANs are a very effective way to execute segmentation: specifically, for segmenting different traffic types—industrial and nonindustrial—as well as creating smaller layer 2 networks. Establish VLANs in a one-to-one relationship with subnets to make routing easier and more straightforward. Devices on a single VLAN are typically assigned IP addresses from the same subnet, and they do not require a layer 3 switch or router to communicate among each other within the VLAN. Using a layer 3 switch or managed switches with layer 2/3 functionality allows communication between VLANs. A management VLAN should be established for management across multiple cell/area zones.

Additionally, using structured cabling for interswitch links and more critical runs in your cell/area zone is a best practice network design approach. Point-to-point cabling is the norm for connecting end-point devices in close proximity.

However, more critical connections can benefit from using industry standards designed to ensure a testable, scalable infrastructure. A structured cabling approach has better organization and testability with patching fields, permanent links, and patch cords that are validated as a high-performance system for rising data rates and high availability. Structured cabling built on TIA-1005 or ENXXX standards have the bandwidth and noise immunity for challenging cell or area zone deployments to ensure uptime.

Designing for production site operationsThe Internet of Things (IoT) has created an

explosion of smart IP–enabled devices that were not traditionally connected to the network. This has created an opportunity to deploy a more flexible architecture with mobile access to data and connectivity within the production environment. Wireless network technology is one of the key enablers for realizing the value of IoT. Wireless technology offers new capabilities, such as “bring your own device” and wireless security cameras, to protect assets and lower





installation and operational costs.Wireless local area networks are significantly different from wired

LANs, and they should be designed for your security, reliability, bandwidth, and throughput requirements. For example, Wi-Fi Protected Access 2 with Advanced Encryption Standard encryption is the only mechanism recommended for control and automation wireless applications, and it should be used in combination with other security methods, such as preshared key authentication.

Wireless channel packet rates should be limited to 2,200 packets per second to help avoid packet delays, and they should be reduced in areas that experience interference and radio-frequency issues. Also, avoid the more heavily used 2.4-GHz band for industrial control applications because you may encounter interference. The 5-GHz band provides dedicated bandwidth and less interference. Conducting a site survey will also help you identify and curtail other potential interference within a production environment.

Virtualization is another key network technology in the connected industrial enterprise. Virtualization breaks the previously unbreakable link between hardware and software, so you can keep industrial applications running beyond the life cycle of their hardware. Virtualization also abandons the traditional one-to-one approach, meaning multiple applications and operating systems can run from a single server.

Important considerations when designing a virtual environment include your applications’ RAM, CPU, and disk I/O requirements, as well as how many applications will be deployed in the virtual environment and the kind of network switching. Take into account your current needs, but also design for growth in the next five to 10 years.

You can engineer and build a virtualized system from scratch, but this approach can be costly and time consuming. You will need to purchase equipment from multiple vendors and spend weeks assembling, installing, and testing the system. An alternative approach is to purchase a bundled virtualization system with preassembled, tested, and validated hardware. Bundled systems also often come with support services, including on-site configuration and integration, which can shave days or even weeks off the deployment process compared to the build-from-scratch approach.

Keep in mind, however, that bundled virtualization systems are produced for a range of industries. It is important to select a system that is custom built for the demands of the industrial environment.

Enterprise integrationA truly converged IT and OT network architecture achieves

seamless integration both horizontally, across multiple sites, and vertically, from the shop floor to the top floor. Doing this requires an understanding of the key techniques that bridge the gap between





historically separate networks.Using fully standard IP networks throughout the architecture,

such as EtherNet/IP for automation communication, eases future application design. Only an IP-centric network infrastructure can help you better use the Internet of Things—which is the proliferation of connected industrial and commercial devices—because it is a unified digital communications fabric on which these IP-enabled devices can talk to each other. A fully standard IP network means your network design is more future proof and can deploy new services or applications without specialized gateways or communication stacks that create integration challenges.

Cloud computing also helps integrate the enterprise. Moving data centers to the cloud simplifies implementation and maintenance, reduces costs, and improves an organization’s agility. However, the cloud still requires a robust physical infrastructure. Factoring in important design considerations—such as deciding what kind of cloud you will use and identifying your bandwidth and cabling requirements—will help you make the most of your cloud investment.

Enterprise integration also cannot occur without considering security. Given the expansion of the network fabric, increased access to sensitive data, and the breadth of cybersecurity threats, designing

in multiple layers of protection should be considered a security best practice. This “defense-in-depth” approach builds a system of safeguards for both digital and physical security, putting multiple security measures in place to counter each individual threat.

Digital security measures include device authentication according to the 802.1X standard, policies that ensure the most recent antivirus updates and security patches are installed, monitoring key network statistics and log files for signs of intrusion, configuring network switches to manage traffic and access, and tightly controlling software used for remote access.

Physical security includes pass codes and access cards to limit personnel access to rooms and connected machines. USB block outs help prevent unauthorized network access, the removal of sensitive information, and the threat of spreading a virus. Lock-in/block-out devices can prevent unwanted plugging and unplugging for copper and fiber connections.

Lastly, an industrial demilitarized zone can be a crucial barrier of protection between the enterprise and industrial zones. It serves as a choke point for all traffic between zones and can help better manage access, such as with authentication enforcement or by monitoring traffic for known threats.





Down to the Wire— Building a Resilient Network Infrastructure

The Internet of Things (IoT) encompasses everyday devices (e.g., smartphones, tablets, video cameras) embedded with technology

that enables these devices to interact in new ways. The IoT also broadens outside the production space to connect Operations Technology (OT) with Information Technology (IT), thereby opening the door to an array of new applications and enhancing existing ones. These new capabilities are further bolstered by a standard Ethernet network, which manufacturers are now adopting on the plant floor as they migrate from proprietary networks.

The IoT revolution is expected to create tremendous business opportunities by 2022, especially in the industrial automation market. This translates into a value of $3.88 trillion linked to manufacturing, according to Industrial-IP.org1 and invites speculation on whether the physical cabling network infrastructure will be able to withstand the IoT flood of data flow.

The right design and cable installation are critical to overall network reliability. According to Gartner2, the average cost of network downtime is estimated to be $5,600 per minute, which is well over $300,000 per hour.

Manufacturers are acutely aware of the repercussions of downtime. In addition to the direct costs associated with down machines tied to the network, challenges exist even when machines are running.

Although a plant may be able to produce manufactured goods, the company may not be able to ship or sell because it lacks quality-controlled electronic documentation, product serialization to track and trace, inventory management, and regulatory compliance data.

Enterprise applications, plant floor software, asset management and quality control applications, predictive analytics, and virus protection systems need a reliable network to work effectively. More importantly, the necessary network is comprised of more than communication protocols. The actual physical infrastructure (i.e., the cables, connectors, wires, cabinets, and panels) is often overlooked. This existing hardware —most of which has been in place for decades—will soon be overtaxed by an influx of networked devices resulting from the IoT movement.

As manufacturers standardize on Ethernet across the organization, they create synchronicity and visibility between the plant floor and the enterprise to achieve gains in efficiency and output. Still, plant managers worry that their existing reliable, proprietary configurations could be degraded in an Ethernet network upgrade. Therefore, it is critical for every CIO, plant manager, and systems integrator to assess each element of the network, from communication protocols to cables, and proactively focus on future needs as they expand or upgrade their network infrastructure.

By Andy Banathy, Solution Architect, Panduit




Pre-Configured Industrial Dis-tribution Frame (IDF)

The Pre-Configured IDF is specifi-cally engineered to deploy and pro-tect rack mount Ethernet switches in industrial applications. Extra-depth allows room for cable management, power management, and switch stack cables and accommodates up to 5 switches. The innovative design provides consistent equipment de-ployment with faster installation and can significantly lower the risk of downtime due to switch overheating.

ContinuedDown to the Wire—Building a Resilient Network Infrastructure

The New Manufacturing ModelToday, organizations are challenged to

transform due to disruptive technologies. From the proliferation of IoT to the globalization of manufacturing, the pressure is on to achieve lower costs, and deliver to new markets.

Manufacturers in the best-in-class category put a greater emphasis on network management, network reliability, and resilience. They build redundancy into network paths as a backup and map out a wiring strategy to ensure that data speed is maximized across the plant floor network. In other words, the “best-in-class network blueprint” plots every aspect of the infrastructure—down to the wire.

“It pays to be forward-thinking with your physical infrastructure,” said Andy Banathy, Solution Architect, Panduit. “Deploying the right media will help avoid performance issues and keep costly upgrades to a minimum. Late in the game, when the network is already deployed, it is very expensive to fix issues,” Banathy said. “In my experience, something that costs $10 in the planning stage may cost $10,000 to fix in the field.”

To turn the reliable, resilient network vision into a reality, companies are defining physical designs and establishing global standards. But before they can proceed, they must conduct an environment evaluation, otherwise known as an assessment.

Assessment StepsManufacturers should complete the steps

outlined below to understand their bandwidth and cable requirements.1. Number of Ethernet Devices

Start the assessment by tallying all the Ethernet devices that require connectivity not only for today, but for the next 10 to 20 years. This may include machines, sensors, cameras, controllers, drives, and switches.2. Environmental Risks

Next, consider the environmental risks to the infrastructure. For example, caustic, wet conditions could affect cable jacket material, and areas with high electrical noise may compromise copper cable. The assessment is also the time to identify obstructions to cable





routing and to optimize cable run lengths. Refer to TIA-1005-A for more information.3. Bandwidth Consumers

After assessing environmental risks, consider the kind of traffic flow to determine bandwidth needs. Examine all the packet-producing devices and estimate data, control, video, and VoIP output needs.4. Downtime

To properly architect the network, it is important to determine the cost of downtime to help establish network investment needs. High downtime costs require design considerations for greater resiliency, cable protection, and pathways.5. Security

The industrial network is not an island. As part of the assessment, manufacturers should determine how to connect with the enterprise network, which has greater security needs due to the number of security attacks on the IT network.

The convergence of enterprise IT and the industrial network means a hacker could wreak havoc in a company’s ability to manufacture. Therefore, it is important to adhere to best practices to build a bullet-proof security scheme when converging IT and plant floor networks. This in-depth defense scheme should cover everything from protocols to port physical security.

The Connected PlantHistorically, the plant floor and the enterprise have remained

separate domains. However, with changing market dynamics that demand just-in-time manufacturing, scalability, and operational visibility, companies are now connecting these disparate networks.

Rockwell Automation and Cisco have developed an architectural model that safely merges the two standards-compliant Ethernet networks. The model, called the Converged Plant-wide Ethernet (CPwE) architecture, is a set of best practices referring to a logical network architecture that extends to the physical layer.

This architecture uses VLANs to efficiently segment traffic across the Layer 2 and Layer 3 network infrastructure; however, all plant control traffic stays below the Demilitarized Zone (DMZ) layer, while any information needed in the enterprise zone is accessed through a server in the DMZ rather than allowing direct traffic between the enterprise and manufacturing compute systems. This setup allows the IT network and the operations network to share data, but they remain virtually isolated, so if the enterprise is breached or a virus is introduced, it cannot reach the production environment.

In addition to security, CPwE also considers planned and unplanned future growth of the network. As Ethernet expands into the manufacturing environment and as a unified architecture is put in place to manage all networking and to control traffic, facilities that





The Impact of Copper Patch Cords on Network Performance

As network infrastructures continue to have a higher impact on produc-tivity, it becomes increasingly impor-tant to select a reliable end-to-end cabling system, allowing for future network growth.

• 100% performance tested

• Patented tangle-free latch

• Keyed patch cords available for improved security


have well-planned and structured physical networks will be best positioned to improve overall operational efficiency, productivity, and flexibility. Refer to the Panduit Industrial Ethernet Physical Infrastructure Reference Architecture Design Guide for more information.

The Industrial Network of the FutureTraditionally, industrial networks have been set

up in a point-to-point configuration, with a single cable terminated to plugs (i.e., a long patch cord). Structured cabling is emerging as a more robust and sustainable infrastructure because it better facilitates growth and troubleshooting, factors that are important to manufacturing. However, there are pros and cons to each approach, depending on the implementation.

Point-to-point is ideal for short cable runs in an enclosure or small ring applications. However, plugs can be hard to terminate. Another consideration is stranded vs. solid cables. Stranded cables lead to reduced distance because of higher attenuation, while a solid conductor cable can break due to flexing. More

importantly, fixed length, point-to-point cables cannot be readily extended or reconfigured as a structured approach with patch panels. In addition, some network test equipment excludes connections to the tester, therefore the entire channel is not tested.

Structured cabling is the preferred implementation for longer and more critical runs, such as connecting enclosures, machines, test equipment, and cameras, as it provides a means for troubleshooting and testability, growth, and reliability. Utilizing patch cords, jacks, and horizontal cabling creates an optimized network channel. Also, the horizontal cable is easier and faster to reliably terminate to a jack versus a plug. By installing network cabling to create spare network channels for growth, technicians can connect to a different channel when adding equipment or in the event of a network cabling failure.

While there is a focus on channel resiliency, the value of structured cabling is its systematic approach to planning and deploying cabling and cable management based on the





Telecommunications Infrastructure Standard for Industrial Premises (TIA-1005-A).

Media SelectionCable media is influenced by cable reach, harsh environments,

electrical noise, bandwidth, and switch convergence. For example, proper copper channel cable transmits 100m while single-mode fiber optic cable can reach distances of many kilometers, depending on the transceiver selection.

Corrosive, wet, and oily environments all impact network cable jackets, causing degradation. There are a variety of outer jacket coverings such as polyurethane, polyvinyl chloride (PVC), and thermoplastic elastomer (TPE), which have varying levels of cable protection. The toughest jacket covering, polyurethane, is abrasion- and tear-resistant, and resistant to oil, radiation, fungus, oxidation, and ozone. Beneath the outer jacket, metallic foil or braid may be used to suppress electrical noise. However, the ultimate in electrical noise immunity is the deployment of fiber.

Another media consideration is bandwidth, especially for large data consumers such as interswitch links and cameras. Bandwidth requirements may necessitate higher category copper such as Category 6 and perhaps multi-mode and single-mode fiber that can transmit up to 10Gb/s.

Recovery time from a network interruption impacts manufacturing downtime. This time can be minimized by deploying fiber cable for interswitch links in rings or redundant star configurations. With fiber the switches recognize loss of signal faster than copper interfaces, and can recover communications much faster than copper. In less complex, smaller networks, copper may be suitable, but the recovery time for network faults needs to be weighed against downtime costs.

Mapping Out Network NecessitiesAt this point, the network assessment is complete, the network

topology is settled, the location of the point-to-point and structured cabling, and the cable construction/media have all been decided. Now it is time to design and deploy the infrastructure, starting with the plant drawing to overlay the logical network architecture on the physical layer.

By having a visual diagram of the network in place prior to the deployment, decisions can be made on routing and the environmental impact on cabling infrastructure. The ISO/IEC 24702 standard has a methodology to assess the environment with four factors - mechanical, ingress, climate, and electromagnetic (referred to as M.I.C.E).

M.I.C.E disruptions can be mitigated with the proper cable jacket covering and shielding to suppress electrical noise.






Keep the following in mind when assessing, designing, and deploying the physical infrastructure:

• Standards-compliant configurations (from TIA cabling standards to EtherNet/IP)

• Cabling methods, (i.e., structured vs. point-to-point)

• Network topology affecting media selection• Fiber optic and copper cabling applications• Appropriate jacket covering and shielding

for harsh environments

Infrastructure MattersIf approached in a systematic manner using

standards-compliant methodology, cabling infrastructure can be a scalable solution that marries the evolving aspects of the logical and

physical networks and can adapt to an ever-changing dynamic industry. Data continuity involves media, wire covering, and topology. In addition, leveraging best practices and certified techniques outlined by technology vendors allows for an efficient and cost-effective installation.

The network must withstand the test of time. Wire it right from the beginning.

(1) Source: Industrial-IP.org(2) Source: Gartner blog, “The Cost of

Downtime” July 16, 2014Referenced Resources

• ANSI/TIA-1005-A Telecommunications Infrastructure Standard for Industrial Premises

• ISO/IEC 24702 – Information Technology – Generic Cabling – Industrial Premises

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Manufacturing Trends and the MES ConnectionImprove your decision making and efficiency by coordinating transformative technologies to work together, rather than considering them unrelated to each other.

When referencing big trends these days—those trends that evolve rapidly and have a significant impact on changing

operations where they are applied—we are often referring to one of four key technologies: the Internet of Things, Big Data, Cloud Computing or Analytics.

• The Internet of Things is a concept wherein devices communicate their status, needs and problems using intelligent sensors to transmit this information over the Internet. Widely distributed sensors and data sources are woven into an autonomous communications network, generating complex and significant aggregated data.

• Big Data identifies the large volumes of data available at high transfer speeds and is characterized by innovative and economic systems that are needed to manage and extract information useful in decision-making. The challenge is storing and processing these data efficiently.

• This combination of technologies within a production management system has the potential to create a vision of the production environment that goes beyond the boundaries of the plant to pervade the entire supply chain from raw material to final customer.

• Cloud Computing usually refers to a system whose processing capabilities are provided through Internet technology and

is scalable, so that the user does not have to acquire and maintain an IT infrastructure, but can simply use a service sized dynamically to suit their needs. Information is available anywhere and to anyone who needs it.

• Analytics is a generic term to identify activities and business intelligence applications relating to a specific domain or specific content. Analytics involve the application of statistical models or mathematical algorithms to the available data in order to predict possible scenarios and support manual or automated decision-making processes. This facilitates the ability to treat data in a complex way, automatically applying algorithms to generate sophisticated information previously available only after extensive manual processing by people with extensive experience.

Each of these technology elements have been generated within IT, but they are not considered closely related or interdependent. However, I believe that there is a different way to look at it. These four trends, each one transformative in and of itself, are, in fact, complementary parts of an overriding movement that is revolutionizing the manufacturing industry.

The combination of all four key pieces outlines a scenario identifiable as the evolution of a single manufacturing execution system (MES) to a new level of pervasiveness and efficiency.

By Luigi De Bernardini




ContinuedManufacturing Trends and the MES Connection

This combination of technologies within a production management system has the potential to create a vision of the production environment that goes beyond the boundaries of the plant to pervade the entire supply chain from raw material to final customer. With real time information available on both the basic components and the finished product, the data generated is of unimaginable value. Production processes can transform themselves constantly, adapting to the market conditions to optimize production times, reduce waste, maximize inventory turns, improve efficiency and, ultimately, ensure the satisfaction of the customer.

The ability to include information collected directly from the finished product in real time adds a whole new dimension to analysis. The end user is the recipient of all the added value of such a production process. Implementation not only requires a reorganization of production processes, with its technological investments, but induces a cultural change related to the fact that each link in the chain cannot independently determine its own strategy. Each link needs to align its strategy with those of the other elements and must behave as one component in the full transformation of the entire system. The alternative is that the chain may end up broken, and your company pulled out of the market.

Increase Your Network Security

Prevent unauthorized access or ac-cidental breaches by establishing a robust physical network infrastruc-ture that offers barriers to network-wide security risks through the use of an integrated physical and logical architecture that includes Panduit Micro Data Centers





Cat5E Beats Cat6 for Industrial Applications

Myth: Category 5E cable is better than Category 6 for industrial applications because its lower bandwidth makes it less

susceptible to electromagnetic interference from VFD drives and other noise sources.

False. Cat6 Unshielded Twisted Pair (UTP) cable systems offer better

noise mitigation than Cat5E because the improved electrical balance of twisted pair cables and RJ45 connectors reduces risk of common mode noise from being converted to differential mode noise that corrupts communication. Cat6 cable’s superior electrical balance arises from the fact that it has more twists per foot, and specs call for better geometry to avoid differential noise coupling.

If the balance is perfect, the differential mode measurements will be equal on both conductors of the twisted pair and thereby cancel out imposed noise.

An analogy to common mode would be a bird sitting on a power line. Both of its feet are exposed to the same high voltage, so no current flows through the bird.

However, if a bird could grab two different power lines, one in each foot, the high voltage difference would cause a large current to flow through the bird. The result: a roasted bird.

Installation of copper Ethernet cabling near control-panel noise sources increases the potential risk for common mode noise coupling that can result in bit errors and delays. Common-mode noise is the voltage that can develop on the entire LAN channel with respect to ground.

Cat6 can be a good choice for UTP installations where higher bandwidth needs and noise concerns are both present. They can be safely used in many automation systems if risks are understood and installation best practices are observed.

• Ethernet infrastructure design techniques for UTP that can improve noise rejection include:

• Maintaining proper bend radius and separation distance between conductors.

• Avoiding over-tightened cable ties.• Using good bonding practices for shielded motor cables.Ensuring cable and connector balance using best-in-class vendor

connectivity solutions that exceed standards specifications.The CMRR (Common-Mode Rejection Ratio) of a cabling system

is a ratio, articulated in dB, of common-mode noise rejected and prevented from converting to a differential mode voltage. IEEE and EIA/TIA defines the minimum requirements for CMRR in terms of transverse conversion loss (TCL) and transverse conversion transfer loss (TCTL), which are power ratio measurements characterizing unbalance from transmit and receive ends. TIA-1005 advises the use of Cat6 connectors for providing improved balance to mitigate noise concerns.

Not all manufacturers design their connectors for optimized balance, so reviewing this critical specification is essential when choosing a connector, as well as patch cable.

Cat6 cables also can provide higher bandwidth potential than Cat5E for demanding future applications (e.g. vision systems, motion control,




etc.) while offering improved noise immunity.If stronger noise mitigation is required due to

close proximity of high noise sources, Shielded Twisted Pair (STP) cable is an option. However, careful attention to bonding and ground loop avoidance are critical for the shield to be effective and not counter-productive. Older

facilities are especially prone to this problem if they do not have low impedance equipotential bonding, and have high power devices and EMI noise sources. The use of robust fiber optic links for long runs and high noise areas provide the ultimate answer for noise avoidance as EMI cannot couple to the light signal.

ContinuedCat5E Beats Cat6 for Industrial Applications

Industrial Myths —Can you distinguish the facts from the fallacies?

“Cat5E Beats Cat6 for Industrial Ap-plications”: Category 5E cable is better than Category 6 for industrial applications because its lower band-width makes it less susceptible to electromagnetic interference from VFD drives and other noise sources. Visit Industrial IP Advantage to un-cover some of the misconceptions around industrial IP today. Test your knowledge and expertise!




Automation MES Network Readiness

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