LEVITON.COM/CROSSTALK 1

When twisted-pair cabling is used for PoE (Power over Ethernet), the majority of the power entering the cable is successfully delivered to the device being powered. However, a small percentage is dissipated in the cabling. This can cause the cable’s temperature to increase above the temperature of its surroundings. It is important to keep cable temperatures at reasonable levels and below the maximum operating temperature. This will:

• Prevent transmission impairment due to structural compromise

• Reduce long-term cable degradation

• Minimize the negative effect of heating on transmission performance

• Reduce the amount of heat added to the surrounding environment

The maximum temperature to which a cable will increase depends on a number of factors, including the amount of power being applied to the cable, the cable’s resistance, the cable’s construction, ambient temperature, and the amount of heat allowed to radiate out of the cable. If cables are bundled or closely grouped, the cables near the center of the bundle have difficulty radiating heat out into the environment. Therefore, the cables in the middle heat up more than those toward the outer surface of the bundle. The larger the bundle size, the more the cables will heat up.

Industry-standard cables carrying PoE at low power levels like 15 and 30 watts are unlikely to overheat, unless extreme conditions exist such as huge bundle sizes or extreme ambient temperatures. It is only when high levels of PoE are deployed — like 100 watts — that heating can become a potential issue.

PRACTICE THE FOLLOWING TIPS TO BETTER MANAGE CABLE TEMPS

IN THIS ISSUE

UPCOMING EVENTS

Tips For Minimizing Cable Temperature Rise in PoE Installations

Simplifying Multifiber Testing

Standards Snapshot

Tech Tips

Ask The Experts

News You Can Use

JANUARY 22-26BICSI Winter ConferenceTampa, FloridaSee page 5 for more information.

Tips For MinimizingCable Temperature Rise in PoE Installations

Simpl ify ingMULTIFIBER TESTING

The emergence of cloud computing has acted as a catalyst for driving even faster adoption of new network technology and higher bandwidth. Projections indicate that by 2018 there will be 2.7 networked devices per person. Data centers need to move quickly to manage these ever-increasing bandwidth demands. While switch-to-switch connections of 40G and 100G accounted for 8 percent of data center infrastructure speeds in 2014, those combined speeds are expected to rise 26 percent by the end of 2016, according to research organization BSRIA.

continued on pg. 2

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LEVITON.COM/CROSSTALK 2

q Use Category 6A in all new cabling installations, unless mandated otherwise. Category 6A for new installs is recommended by the Telecommunications Industry Association (TIA).

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q Use horizontal cables and patch cords that have larger copper conductors (i.e., lower wire gage numbers). These larger conductors will heat up less and perform better than smaller conductors.

CM 75o

C 4PR 26 AWG

q Consider using cables with higher temperature ratings such as 70, 75, or 90ºC rated cable, but always try to keep the maximum ambient temperature at reasonable levels. A good target is 45 ºC, which allows for a 15 ºC temperature rise due to PoE for a 60°C listed cable. For higher maximum ambient temperatures, seek professional design assistance.

q Consider using a shielded cabling system, or unshielded cables with a segmented metallic isolation wrap. These cables dissipate heat better than traditional UTP cable, minimizing the cables’ temperature rise.

q Plan for cable management and trays to use minimal fill rates to allow for expansion — less than 50 percent is ideal.

q Use wire cable trays or similar cable management that allows for largely unrestricted airflow around the cables or cable bundles. And unbundled cables in wire basket trays will exhibit less heat rise than cables held together as a bundle for at least six feet.

q Loosely group cables when possible, rather than bundling. If bundling is required, loosely bundle cables in the smallest bundle size that suits the needs of the installation.

• • • • q Evenly distribute cables or cable bundles within the available area.

Tips For Minimizing Cable Temperature Rise in PoE Installations • continued from pg. 1

þ The following list of general installation practices will help minimize heating in cables carrying any level of PoE.

continued on pg. 3

LEVITON.COM/CROSSTALK 3

q Minimize the number of cable ties used to secure the cables. Apply with minimal tension. Consider VELCRO® Brand fasteners, which are less likely to crush or damage cables.

q Avoid cramming or “necking down” cables into small areas such as conduit sleeves between rooms. Provide as large an area possible for this transition. If the available area is limited, loosely arrange cables (birdcage them) on either side of this area to help dissipate heat.

Plastic

Metal

q Use connectors with an all-metal-body construction, instead of plastic. Leviton PoE tests of connector bodies found that metal bodies create a 53 percent improvement in heat dissipation.

Adhere to MAX bundle size limits

q Adhere to the limits for maximum bundle sizes given in applicable codes and/or the cable manufacturer's specifications.

q Use minimal bundles sizes for long cable runs carrying high-wattage PoE (70 meters and longer). This minimizes the temperature rise — and resulting increases in attenuation — enabling you to avoid having to substantially derate (shorten) cables as dictated by ANSI/TIA-568-C.2 Annex G.

Seek advice from

INDUSTRY EXPERTS

q Seek advice from industry experts, including those at Leviton. Call our technical staff at 800-824-3005, or learn more about cabling and connectivity for PoE at Leviton.com/PoE.

Tips For Minimizing Cable Temperature Rise in PoE Installations • continued from pg. 2

These tips are not intended to supersede or take place of any governing standards. Cabling intended to carry PoE should be installed in accordance with all building codes applicable to the given locality including the National Electric Code. TIA’s TSB-184-A and ISO/IEC TR 29125 can also provide additional information for facilitating installation.

Leviton offers structured cabling systems that meet the need for higher bandwidth and power, while limiting the temperature rise in large cable bundles. They are designed and tested to be compliant with all current IEEE PoE standards, Power over HDBaseT, and IEC 60512-99-001. And Leviton Altas-X1TM Cat 6A connectivity has been tested to deliver 100-watt PoE, as defined in the draft IEEE 802.3bt (Type 4) standard.

Learn more about Leviton systems that supports PoE at Leviton.com/PoE.

LEVITON.COM/CROSSTALK 4

Simplifying Multifiber Testing • continued from pg. 1

40G Networks Require Simpler Testing

By 2017, 40G speeds will be in significant demand, becoming almost commonplace as we start to see more 100G networks being regularly deployed near 2020. Multifiber installation and testing best practices will be critical to maintaining a competitive edge as network migration strategies evolve. And while the idea of multifiber testing is intimidating, having the right training, tools, and methods will simplify the process and provide the forward-thinking strategies needed to help grow your business and reputation.

As an installer, you understand the importance of having the right tool for the job. When conducting multifiber testing there are a number of different testing methods to choose from, but not all methods are ideal for providing optimal results.

Testers used to confirm 10G channels are capable of conducting 40G testing. However, testing with these older devices requires considerably more time, adds additional steps to the process, and increases the probability for human error. Most multifiber testers can get the job done 15 times faster than standard LC testers. And by reducing the number of testing steps you minimize inaccuracies.

Investing in a Multifiber Tester

While using a duplex tester to conduct 40G (SR4) testing can save you money in the short term, the amount of additional time spent on site will quickly offset any potential cost savings. Investing in a multifiber tester is a significant commitment, but if you want to stay competitive you will need to familiarize yourself with these tools in the near future. The added benefits will compensate for the initial investment cost.

By using a multifiber tester, you can expect:

• Faster setup and less time spent conducting tests on site

• Actual test reports, minimizing the need for documentation

• Fewer patch cords and harnesses needed for testing

• Better verification of the polarity method for tested channels

0.000

Looking Forward

The same tools and methods recommended for 40G (SR4) multifiber testing also apply to 100G (SR4) multifiber testing. By becoming familiar with these methods now, you can stay competitive while maintaining your capability to assist customers with future migrations.

For a comprehensive look at 40G multifiber testing methods, take a look at Leviton’s white paper: The Method Behind the Magic, Multifiber Testing.

For assistance, contact Leviton's technical support team at appeng@leviton.com.

Pay us a visit at BICSI Booth 637,to see the latest in data center connectivity.

Also, don’t miss these seminars from Leviton experts:

Learn from Leviton at the BICSI Winter Conference

January 22 - 26, 2017Tampa, Florida

IT/AV and HDBaseT Control Signals: This Changes Everything

Presenter: Bill Lauby, LevitonWednesday, January 25 9:00 – 10:00 a.m. (EST)

Designing a Flexible Network Infrastructure to Support New Optical Technologies

Presenter: Gary Bernstein, Leviton Wednesday, January 25 10:30 – 11:30 a.m. (EST)

The PoE Market is Heating Up: What You Need to Know For Best-In-Class PoE Systems

Presenter: Todd Harpel, Berk-Tek Leviton TechnologiesThursday, January 26 9:15 – 10:00 a.m. (EST)

Day1/25

Day1/25

Day1/26

LEVITON.COM/CROSSTALK 5

STANDARDS SNAPSHOTKeeping you up to date on important developments from IEEE, TIA, and BICSI.

2017 National Electric Code

In June, the National Fire Protection Association (NFPA) voted to make changes to the 2017 National Electric Code (NEC) that imposes limits on the maximum number of cables allowed in a bundle for PoE application above 60 watts. The changes are based on a fact-finding report conducted by Underwriters Laboratory (UL).

New Ampacity Table and Derating Chart

The 2017 NEC includes a new ampacity table, 725.144, to be used when installing conventional telecommunications cables and using PoE levels greater than 60 watts. Values for the highest allowable amount of current are given in the table based on the cable’s temperature rating and specified bundles size ranges. However, this table only applies at an ambient temperature of 30 °C or less. For higher temperatures, the derating chart 310.15(B)(2) must be used, which lowers the allowable amount of current as maximum ambient temperature increases.

The updated NEC also includes the new optional LP cable classification. LP cables can act as an alternative to conventional cables and the new ampacity table, as they can be installed without regard to bundle size up to the current level imprinted on the cable jacket. The letters “LP” are imprinted on the jacket, followed by the ampacity rating, such as “LP (0.5A)”, “LP (0.6A)”, “LP (0.7A)”, etc. However, these installations are only valid up to 30ºC maximum ambient. Above 30 ºC, the appropriate current derating table in the code needs to be used. LP cables would not be mandated by the new NEC to be published in 2017, but included as an option.

For PoE installation at 60 watts and below, nothing has changed in the code and the NEC places no new restrictions on bundle size. In addition, consult TIA TSB-184/A, ISO/IEC TR 29125, manufacturer recommendations, BICSI installation practices, and any local applicable codes, for additional guidance on cable installation. They also included a new optional classification of cables for PoE called Limited Power (LP), which can be installed without regards to bundle size.

IEEE 802.3bz

In September, IEEE ratified 802.3bz, which defines 2.5 and 5 Gigabit Ethernet over twisted pair cabling (2.5GBASE-T and 5GBASE-T). The new standard also includes a wireless component for 2.5G and 5G Ethernet that allows connectivity with 802.11ac Wave 2 Access Points. The standard will allow for upgrades to these multi-gigabit speeds using existing category 5e and 6 cabling.

TIA

The ANSI/TIA-1152-A standard for Category 8 field testing was approved for publication, and is expected to be available for purchase by the end of the year. Cat 8 specifications in ANSI/TIA-568-C.2-1 were approved in June 2016.

TSB-184-A, which offers guidelines for power delivery over twisted-pair cabling, has progressed to a Default Ballot, and tables identifying maximum bundle sizes allowed for various category cables under power have been finalized. The document should publish in early 2017.

TSB-5021, which offers guidelines for supporting 2.5/5G over Cat 5e/6, has progressed to a first Default Ballot. This document has been pre-approved for publication if the ballot closes “clean” (without any no votes).

The ANSI/TIA-1179-A Healthcare Infrastructure standard has progressed to the 2nd Industry Ballot. This document is likely to be approved to publish following the February 2017 meeting.

ANSI/TIA-942-B, which covers infrastructure requirements for data centers, has progressed to the Industry Ballot stage, and is likely to publish after the June 2017 meeting.

ISO/IEC

In early October 2016, the ISO/IEC announced that cabling using wideband multimode fiber (WBMMF) will be called OM5. This will be published in ISO/IEC 11801, Edition 3. The ANSI/TIA-492AAAE standard for WBMMF was approved in July 2016.

6

NEWS USEYOUCAN

YESTERDAY’S NEWS1991: 25 years ago, computer scientist Tim Berners-Lee introduced the World Wide Web to the public. He designed and deployed the Web at the European Organization for Nuclear Research (CERN) in Switzerland.

WEBCheck out Leviton.com/ITAVtool for a great utility to help you design an IT/AV solution. Just answer a few questions, and our Technical Services Reps will provide a detailed bill of materials and a diagram of products and connectivity needed to

extend audio, video, and data signals over a single- category cable permanent link.

Also, contractor project managers and estimators should check out our series of IT/AV design webinars on the Leviton ez-Learn site. These training modules cover HDBaseT™, IT/AV systems for education, and the Leviton IT/AV product line. The modules are free and every participant receives a certificate of completion.

ASK THE EXPERTS

INDUSTRYOver the next several years, the Ethernet switch market will see the rise of two significant upgrade cycles: campuses moving to 2.5Gb/s and 5Gb/s, and data centers migrating towards 25Gb/s and 100Gb/s. That’s according to a recent Ethernet switch forecast from the Dell’Oro Group.

COMPANYLeviton has launched a new mini-site dedicated to Home Solutions. You can learn about all of Leviton’s solutions and products by searching through specific rooms within a home, or by application (e.g., automation, networking, energy savings, etc.) Explore today at home.Leviton.com.

ü Pull-through cable length should not exceed 300 meters (984 ft.) in length

ü Locate centralized cables in the same building as the centralizedcross-connect

ü Perform all moves, adds, and changes at the centralized cross-connect

ü Allow for migration of the pull-through, interconnect, or splice to a cross-connect

ü Leave sufficient space in the HDA to allow for additional patch panels to be added for migration to a cross-connect

ü Provide sufficient cable slack in the HDA to allow for a cross-connect

ü Stored cable slack may be jacketed or unjacketed. Slack should be stored in a protective enclosures in the equipment rack or cabinet

ü Provide enough bend radius control so that the cable and bend radiuslimitations are not exceeded

6Email: crosstalk@leviton.com

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© 2016 Leviton Manufacturing Co., Inc.

Centralized Optical F i b e r G u i d e l i n e s

Q: How do I test an HDBase-T link?

A: Field-testing HDMI® signals is generally impractical, but there are a number of reliable testers available that provide a reference HDMI source and a reference sink. They are useful for monitoring HDCP key sets, EDID transactions, and hot-plug events. However, most testers are not suitable for field-testing an end-to-end link and the relative expense of the tester often outweighs the benefits.

The best way to ensure dependable signal performance over an IT/AV system, and avoid video signal loss, is to use category 6A cabling installed in line with BICSI practices and tested and certified with the manufacturer. However, when encountering performance issues, there are a few steps you can take to fix video signal loss. This starts by dividing and isolating the power, HDBaseT™ link, HDCP at TX (transmitter) and Rx (receiver), category cable link, and extender hardware.

A standardized approach can often provide better testing results at a lower cost. Standard testing of the category cable infrastructure relies on extensive TIA, ISO, and IEC standards, and there are a number of field-proven test instruments readily available. Plus, industry-standard field testers often allow contractors to certify and warrant the cable link, providing customers added peace of mind.

Some enterprise and internet data centers implement data networks with centralized electronics rather than using horizontal cross-connects in their main distribution area (MDA). The equipment racks (EDAs) connect directly to the centralized cross-connect in the MDA using pull-through cables, an interconnection, or splice in the horizontal distribution area (HDA).

Here are some general cabling guidelines for a centralized topology:

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