Power over Ethernet (PoE) offers convenience, flexibility, and enhanced management capabilities by enabling power to be delivered over the same CAT5 cabling as data. This technology is especially useful for powering IP telephones, wireless LAN access points, cameras with pan tilt and zoom (PTZ), remote Ethernet switches, embedded computers, thin clients and LCDs.
The original IEEE 802.3af-2003 PoE standard provides up to 15.4 W of DC power (minimum 44 V DC and 350 mA) supplied to each device. The IEEE standard for PoE requires Category 5 cable or higher (can operate with category 3 cable for low power levels).
The updated IEEE 802.3at-2009 PoE standard also known as PoE+ or PoE plus, provides up to 25.5 W of power.
Although 2009 standard prohibits a powered device from using all four pairs for power, some vendors have announced products that claim to be compatible with the 802.3at standard and offer up to 51 W of power over a single cable by utilizing all four pairs in the Category 5 cable. The trend for power demands seem to be up.
Compliance to Power-over-Ethernet safety standards is critical when moving beyond 60W (EE Times)and Compliance with POE safety standards is critical when moving beyond 60W (EDN) articles tells that the current generation of standards-based technology enables up to 60 watts of power to be delivered over four pairs of cabling, which also improves efficiency when compared to earlier two-pair solutions. Compliance with POE safety standards is critical when moving beyond 60W.
As the industry moves toward delivering even more power over the CAT5-or-better cabling infrastructure, system designers and network administrators alike, need to understand various emerging technology options. Some new options can bring expensive and cumbersome deployment complications and, potentially, safety risks.
Some manufacturers have touted their own 100W-per-port solutions or even 200W/port solutions that are not safe. The use of a standard Ethernet-cabling infrastructure for a single port delivering greater than 100W is simply not safe under the NEC standard. The only safe approach for powering devices over Ethernet cabling is to follow IEEE802.3at-2009 specifications. Moving beyond the LPS requirement (sub-100W/port LPS requirement of IEC 60950-1:2011) to greater-than-100W/port implementations requires that the cables be protected with special flame-resistant conduit. A metal enclosure is required if the total PD load is greater than 100W for information data equipment, or greater than 15W for TV and audio equipment.
One standardized 100W solution is one used by HDBaseT Alliance. HDBaseT Alliance is develops 100W power specifications for products that transport uncompressed, high-bandwidth multimedia content, 100BaseT Ethernet, power, and various control signals through a single LAN cable. The key differences between the HDBaseT-powering approach and those from other independent manufacturers pursuing higher power levels are that it:
- Complies with the section 33.7.1 of the IEEE802.3at-2009 standard, which mandates that all PSEs conform to International Electrotechnical Commission (IEC) 60950-1:2001 specifications including classification as a Limited Power Source (LPS) carrying no more than 100 volt-ampere (VA) – or 100W – per port without the need for special over-current protection devices, and
- Performs Powered Device (PD) detection followed by PD classification to determine a PD’s consumed power level prior to its ignition.
In a typical HDBaseT implementation, the PSE is installed and powered by a 50 to 57-volt DC power supply, and all PDs receive power directly over the HDBaseT link across all four pairs of CAT5-or-better cables. Additionally, core PoE technology has been enhanced for HDBaseT to use a 1 amp current for every two cabling pairs, 3-event classification to identify compliant PSEs, and identify the cable length/resistance (draw more power when required not exceeding 100W, rather than assuming a worst-case cabling infrastructure at all times). This enables HDBaseT technology to transfer of up to 100W of continuous DC power, per port, from one side of the HDBaseT link to the other.
HDBaseT’s ability to deliver up to 100W of power (over 100m, via a single LAN cable, without any additional power source) is actually very nicely aligned with trends in energy usage and demand. The power level is more than adequate for supporting today’s typical 40-inch LED TV, which requires 70W of power. It is expected that both LCD and LED TV monitors will soon be averaging approximately one watt of power consumption per inch of screen size. Regardless of screen size EnergyStar™ 6.0 is targeting a cap of 85 W for all screen sizes.
PoE continues to evolve and offer an even wider variety of high-value power-delivery and management capabilities.
257 Comments
Tomi Engdahl says:
The case for Cat 6A over Cat 5e in PoE applications
http://www.cablinginstall.com/index/display/article-display/8929047725/articles/cabling-installation-maintenance/news/network-cable/cat6a/2012/august/Cat-6A-vs-Cat-5e-PoE.html?cmpid=EnlCIMSeptember42012
A paper authored by General Cable data-communications products engineer Rob Gould makes the case for the use of Category 6A cabling rather than Category 5e cabling for applications in which Power over Ethernet (PoE) will be employed.
the paper provides documentation of testing under which Cat 5e performance was compared to Cat 6A performance supporting a VoIP phone drawing 4.93 watts and a wireless access point drawing 7.5 watts of DC power.
In the case of the VoIP phone, on the Category 5e circuit approximately 82 milliwatts of power were dissipated, while on the Category 6A circuit approximately 56 milliwatts were dissipated.
The paper then calculates long-term savings, in electricity costs, that will be gained by the use of Category 6A rather than Category 5e cabling. It later expands the findings to PoE Plus scenarios.
Paper:
http://www.generalcable.com/NR/rdonlyres/DD2FE586-375B-4893-803B-DA6AD06A55CB/0/ComparativePoETestingBetweenCategory6AandCategory5eCables8_09.pdf
Tomi Engdahl says:
How using Power over Ethernet can save users $300 a year in energy costs
http://www.cablinginstall.com/index/display/article-display/8416993404/articles/cabling-installation-maintenance/news/wireless/2011/6/How-using-Power-over-Ethernet-can-save-users-300-a-year-in-energy-costs.html
Midspan PoE devices’ ability to monitor, reduce and manage power use offers network administrators the biggest opportunity to significantly reduce energy consumption and associated costs.
Today’s midspans feature two interfaces, each of which takes 25.5W into the same box — one over the pairs using pins 1, 2, 3 and 6 and the other over the pairs using pins 4, 5, 7 and 8. Connecting the two doubles the standard power delivery to 51W while still fully complying with the 802.3at-2009 standard. Alternatively, four-pair powering can be used to cut power dissipation
The next tactic for improving efficiency is to use midspans’ remote powered device (PD) monitoring and configuration capabilities. Network administrators can monitor per-port and total power consumption, and configure PDs for instant and scheduled port on/off functions, as well as UPS status port on/off functions.
The third way to improve power efficiency is to minimize the effects of idle power consumption.
Calculating the aggregate savings possible with each of these approaches, organizations can save more than $300 annually using the latest energy-efficient PoE midspan technology. This includes the following.
Four-pair powering: Saves 2W per port or $53/year
Power management: Saves $210/year by enabling ports to be turned off when not needed
Smaller internal supplies (augmented with external supplies as needed): Saves $39/year by reducing idle power consumption.
Tomi Engdahl says:
A paper authored by General Cable data-communications products engineer Rob Gould makes the case for the use of Category 6A cabling rather than Category 5e cabling for applications in which Power over Ethernet (PoE) will be employed.
The paper then calculates long-term savings, in electricity costs, that will be gained by the use of Category 6A rather than Category 5e cabling. It later expands the findings to PoE Plus scenarios.
In the paper’s conclusion, Gould states, “With the world’s ever-growing demand for energy, finding new and more-efficient ways to deliver it is essential. PoE not only decreases infrastructure material, when run over Cat 6A, it delivers power more efficiently. For customers seeking high efficiency and future growth potential with their networks, once choice for PoE stands above the rest – Cat 6A cable.”
Paper can be downloaded at
http://www.generalcable.com/NR/rdonlyres/DD2FE586-375B-4893-803B-DA6AD06A55CB/0/ComparativePoETestingBetweenCategory6AandCategory5eCables8_09.pdf
Tomi Engdahl says:
White papers contrast EEPoE vs. EEE
http://www.cablinginstall.com/index/display/article-display/4884728275/articles/cabling-installation-maintenance/news/cabling-standards/ieee/2012/august/white-papers_contrast.html
Felicidad Forgione says:
LED TV are the best since they consume less electricity. .
Latest short article on our internet page
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Tomi Engdahl says:
New PoE PD device family by Texas Instruments
http://www.edn.com/electronics-products/electronic-product-reviews/other/4400631/New-POE-PD-device-family-by-Texas-Instruments?cid=EDNToday
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Tomi Engdahl says:
IEEE forms 4-pair Power over Ethernet Study Group
http://www.cablinginstall.com/articles/2013/04/ieee-4pair-poe.html
The Institute of Electrical and Electronics Engineers (IEEE) announced it has formed a new study group to consider initiating a formal project to standardize four-pair Power over Ethernet (PoE). The 4-pair Power over Ethernet Study Group will consider a four-pair solution’s capability to enhance energy efficiency and provide greater than 25.5 Watts of power in improving PoE.
“The formation of this study group will allow collaboration on a proposal for the development of a four-pair PoE standard, which would allow support of new PoE applications in the areas of IPTV, industrial Ethernet and more. A four-pair approach would result in increased efficiency, since the use of additional pairs results in lower channel resistance.”
“PoE has become the dominant powering method in many Ethernet-based products—access points and IP phones, for example—demonstrating that customers will migrate toward convenience. Enabling applications beyond 25.5 Watts will extend this convenience to other products”
Tomi Engdahl says:
Surge Protection Brings Big Benefi ts to PoE Systems
http://powerelectronics.com/site-files/powerelectronics.com/files/archive/powerelectronics.com/power-over-ethernet/703PET22.pdf
Understanding the various causes and characteristics of electrical transients enables designers to safeguard PoE systems from these events with discrete protection circuitry.
In PoE applications, PSE is powered from a 48-V power
supply. Normally, this has some common-mode capacitances
connected to earth-ground. Those capacitances can be either
discrete capacitors, interlayer capacitance in the pc board
or a combination of both types. Since the PSE is not really
fl oating, any common-mode voltage transient applied on
the data connector can result in a voltage breakdown of PSE
components. This is especially true for a PSE port power-
switch transistor.
In an application where RJ-45 cables are used, the previ-
ously mentioned protection technique of cable shielding
is usually not an option.
Tomi Engdahl says:
Siemon white paper investigates remote power delivery over twisted-pair cabling
http://www.cablinginstall.com/articles/2013/07/siemon-remote-power-paper.html
Siemon has produced a new white paper offering information and insight on the latest standards, trends and best practices for deploying remote power to network devices. The detailed, 4-page whitepaper is titled The Advantages of Using Siemon Shielded Cabling to Power Remote Network Devices, and highlights the specific technological advantages of using the company’s shielded cabling systems for Power over Ethernet (PoE) and other remote powering applications.
With more than 100 million PoE-enabled ports purchased annually, a new 4-pair IEEE 802.3 PoE application on the horizon, and advanced standards-based technology ready to deliver up to 100 watts of power (i.e. enough to power a television), Siemon contends that the need to deliver DC power over twisted-pair cabling “has revolutionized the look and feel of the IT world.”
“As the market for remotely powered IP devices continues to grow and even more advanced powering technology is deployed, the ability for connectors and cable to perform under DC power load conditions has emerged as a critical factor,” comments Valerie Maguire, Global Sales Engineer for Siemon.
Tomi Engdahl says:
60-watt Power over Ethernet injector
http://www.cablinginstall.com/articles/2013/04/moxa-60w-poe.html
Moxa recently introduced the INJ-24A Gigabit High-Power PoE+ Injector, which the company says is capable of transmitting 60 watts of power to any powered device, along with data, “allowing devices on 10/100/1000 networks to safely operate with twice the power of conventional PoE+,” the company says.
“This versatility means that the INJ-24A can supply power to nearly any PoE device with minimal compatibility obstacles because it can quickly reconfigure to match the device’s settings.”
About the need for high-powered PoE devices, Moxa noted, “Networks deployed in outdoor environments would seem like a natural fit for PoE+ technology since outdoor network devices are more difficult to wire and require more costly cables. However, because PoE+ technology can only deliver 30W, it often comes up short outdoors where power-hungry IP cameras, wireless access points or RF modems require added wattage for such things as heating units or integrated wipers. In addition, most commercial PoE connections are not robust enough to withstand static discharge, extreme hot or cold temperatures, power surges and other environmental punishments.
The built-in 24/48 VDC booster enables the injector to operate on either 24 VDC or 48 VDC.”
Tomi Engdahl says:
PoE touchscreen terminals suit digital signage, industrial automation apps
http://www.cablinginstall.com/articles/2010/08/poe-touchscreen-terminals.html
American Industrial Systems Inc. (AIS) has introduced another line of Power over Ethernet (PoE) touchscreen panel PCs, available in 5.7”, 7”, and 10.1” compact form factor sizes.
The units support the latest PoE standard IEEE 802.3at for up to 25.5 Watt power transmission capability over a standard Cat 5 cable. AIS says the new line of PoE wall mount touchscreen terminals are especially geared for industrial automation, transportation, appliance and digital signage applications.
The company notes that Power over Ethernet or PoE technology describes a system to safely transfer electrical power, along with data, to remote devices over standard category 5 cable in an Ethernet network. It does not require modification of existing Ethernet cabling infrastructure.
AIS says its Power over Ethernet (POE) enabled HMI PCs follow the IEEE 802.3af, IEEE 802.3at integrated data and power industry standards for direct drop in deployment for new and existing PoE systems.
AIS’s PoE touchscreen panel PCs to enable hospital digital signage, patient monitoring
http://www.cablinginstall.com/articles/2013/10/hillrom-ais-hospital-poe.html
Hill-Rom, a major provider of medical technologies and related services for the health care industry, has selected American Industrial Systems (AIS), a specialist in HMI [human machine interface] and digital signage display technologies, to supply its Power over Ethernet (PoE) touch panel mount PCs for hospital electronic signage solutions outside patient rooms.
Hill-Rom’s electronic signage solution utilizes the AIS 10.1” touch screen panel PC computers for displaying digital messaging outside a hospital patient room and can help eliminate the need for paper signage that can be outdated and incorrect.
“The open platform design of our touch screen panel PCs delivers unmatched flexibility and performance for healthcare digital signage and patient display/monitoring applications,”
AIS notes that its 10.1” PoE touch screen panel PCs are also ideal for industrial machine manufacturing, process and discrete manufacturing, industrial automation, building automation and custom HMI applications.
Tomi Engdahl says:
Omnitron integrates PoE to directly power small cell equipment
http://www.cablinginstall.com/articles/2013/10/omnitron-poe-small-cell.html
Omnitron Systems has launched its GM4-PoE, billed as the first Carrier Ethernet (CE) 2.0 Network Interface Device that integrates up to 60W Power over Ethernet (PoE) to directly power small cell equipment, thereby reducing service providers’ total cost of ownership (TCO).
GM4-PoE NIDs are available in two PoE basic models; GM4-PoE+ and GM4-HPoE. Both models support the 802.3af PoE (15.4W) and 802.3at PoE+ (25.5W) standards per port, while the GM4-HPoE models also provide up to 60W of power per port.
The GM4-PoE NIDs also feature Zero-Touch Provisioning, ITU-T Y.1564 and RFC 2544 Service Activation Testing to simplify and automate large scale small cell deployments. Comprehensive support for ITU-T Y.1731 performance monitoring
IEEE 802.1ag Connectivity Fault Management
“Complexity, power requirements and high backhaul equipment cost have been critical factors slowing down small cell deployments,” comments Rammy Bahalul, Omnitron’s vice president of marketing.
Tomi Engdahl says:
Panasonic joins HDBaseT Alliance
http://www.cablinginstall.com/articles/2013/12/panasonic-joins-hdbaset.html
The HDBaseT Alliance announced that Panasonic is now a Contributor member of the Alliance.
Panasonic has played an integral role in the development and deployment of the HDBaseT technology since its introduction in 2010, and offers a number of HDBaseT-enabled projectors and commercial displays.
Referred to as DIGITAL LINK, the HDBaseT enabled projectors and displays enable a single Cat 5e and above cable to transmit uncompressed HD videos, audio and control commands up to 100 meters.
Tomi Engdahl says:
Cat5e data and 250W power in a single cable
http://www.edn-europe.com/en/cat5e-data-and-250w-power-in-a-single-cable.html?cmp_id=7&news_id=10003629&vID=1323#.Uz0K8VdM0ik
Available at distributor TTI, TE Connectivity’s CLOUDSPLITTER Connector System combines eight signal and two power positions: applications include intelligent building management, video surveillance over IP networks, factory automation, and wireless network transceivers
Electrical characteristics for the CLOUDSPLITTER Connector System are 1.5A/150 VAC/DC for signal data and it provides DC power at 5A up to 50 VDC over two integrated power contacts. Operating temperature range is -40C to +85C.
the CLOUDSPLITTER SMT RJ45 modular jack accepts either CLOUDSPLITTER or standard RJ45 shielded plugs.
Tomi Engdahl says:
HDBaseT Alliance demos single-cable 4K video delivery at NAB 2014
http://www.cablinginstall.com/articles/2014/04/hdbaset-nab-single-cable-4kvideo.html
The HDBaseT Alliance’s booth at NAB (#SU 11914) will feature live demonstrations of how HDBaseT technology can deliver 4K video over a single cable over long distances to significantly reduce the costs and complexities of installations. These demonstrations will be based on products by several HDBaseT Alliance members and partners including: Apantac, Gefen, Keisoku, Kramer, and Muxlab. Additionally, the Alliance will showcase new HDBaseT-enabled displays from manufacturers such as Panasonic, NEC, Samsung and Primeview.
HDBaseT technology enables all-in-one connectivity between HD video sources and remote displays through a single 100m CAT5e/6 cable, delivering uncompressed high definition video, including 4K, audio, Ethernet, control signals and up to 100 watts of power.
Tomi Engdahl says:
Unraveling HDBaseT signaling over bundled cables
http://www.cablinginstall.com/articles/2012/12/belden-hdbaset-report.html
A white paper from Belden authored by Paul Kish, the company’s director of systems and standards, takes as its premise that “it has been reported in the field that there are cases where multiple HDBaseT signals in separate cables that share the same pathway can interfere with one another causing a loss of signal (a dropped link) or a degraded picture.”
Tomi Engdahl says:
Ethernet Alliance considering Power over Ethernet logo certification program
http://www.cablinginstall.com/articles/2014/07/ethernet-alliance-poe-logo.html
The Ethernet Alliance announced that it is inviting the Ethernet industry as a whole to join the consortium in an open discussion of a proposed Ethernet Alliance Power over Ethernet (PoE) technology logo certification program (#LogoPoE).
“We believe an industry-driven logo certification program will help promote greater interoperability between IEEE 802.3-standardized PoE solutions. Additionally, a logo certification program will help end users more easily identify PoE products that have undergone Ethernet Alliance PoE logo certification and better ensure their performance, helping to further PoE’s rapid adoption across a broad array of markets and applications, like the coming Internet of Things.”
Tomi Engdahl says:
Compact Ethernet repeater handles up to 60W of PoE power
http://www.cablinginstall.com/articles/2014/07/vigitron-poe-repeater.html?cmpid=EnlCIMJuly282014
Vigitron has introduced its compact Vi3002 Ethernet and PoE ++ repeater, designed for applications that require extended distance transmission of both IP video and PoE with distances up to 656 ft. (200m).
The Vi3002 repeater uses Vigitron’s patent-pending Pass-Through-PoE technology to handle PoE power up to 60W. This feature enables the Vi3002 to be used with most high performance PTZ IP cameras by major manufactures, requiring more than the standard 802.3at (30W) power inputs.
Tomi Engdahl says:
Emerging PoE standard aiming for 49W per-port minimum
http://www.cablinginstall.com/articles/print/volume-22/issue-7/features/technology/emerging-poe-standard-aiming-for-49w-per-port-minimum.html?cmpid=EnlCIMJuly282014
The high-power promise of IEEE 802.3bt carries with it certain demands of a network’s twisted-pair cabling infrastructure.
When the IEEE formed a study group in early 2013 to examine the possibility of a four-pair PoE specification, it said the group would “consider a four-pair solution’s capability to enhance energy efficiency and provide greater than 25.5 watts of power in improving PoE.”
Since that time, the effort has received a project authorization request (PAR) approval and is now officially in development as 802.3bt.
Vanderlaan pointed out the two different means of supplying power per 802.3af, called Alternative A and Alternative B. Each of these alternatives used two of the cable’s four pairs for power transmission.
IEEE 802.3at (commonly referred to as “PoE Plus” but not officially called that in the standard) was ratified in 2009. Along with increasing power delivery to 25.5 watts with 600 mA, the PoE Plus standard also raised the minimum cabling-performance requirement to Category 5.
research has shown that a PoE variant using all four pairs to deliver power is more efficient than the currently standardized two-pair variants in the “af” and “at” standards.
The other objectives for the “bt” standard are: to be backward-compatible with “af” and “at”; to support 10GBase-T operation (which, like 1000Base-T, uses four-pair full-duplex transmission); to specify parameters to limit pair-to-pair current imbalance; and to supply a minimum of 49 watts at the powered device. More on that 49-watt minimum shortly.
several have brought to market device-powering systems that are not standardized by the IEEE
Cisco’s Universal Power Over Ethernet (UPOE) technology, which delivers 60 watts of power to devices and was introduced in mid-2011
The year 2011 also saw the introduction of Power Over HDBase-T by the HDBase-T Alliance
“delivers up to 100 watts of power to TVs and other devices over distances up to 100 meters/320 feet via a single Category 5e or 6 cable with standard RJ45 connectors.”
“As a general rule, increased copper content, or larger gauge size, will aid in power delivery. That’s not always the case, but in general it can be said that when you migrate to a higher grade of cabling-from Category 5e to Category 6 to Category 6A-you should see larger gauge sizes and more copper content.”
“The IEEE 802.3bt four-pair PoE standard is expected to assume a maximum temperature rise of 10 degrees Celsius when all four pairs are energized. For cabling with an operational temperature range of -20 degrees Celsius to 60 degrees Celsius, the ambient temperature should not exceed 50 degrees Celsius. Using a higher category cable with lower DC resistance and improved heat dissipation can help reduce the rise in temperature. Consequently, CommScope recommends Category 6A cabling for four-pair PoE applications.”
Tomi Engdahl says:
Quad, IEEE 802.3at/af PSE Controller
http://www.eeweb.com/company-news/maxim/quad-ieee-802.3ataf-pse-controller/
The MAX5980A is a power-sourcing equipment (PSE) power controller developed by Maxim Integrated to address the need of highly efficient powering device that will energise Ethernet cables at long distances.
The MAX5980A is a quad, power-sourcing equipment (PSE) power controller designed for use in IEEE® 802.3at/af-compliant PSE. This device provides powered device (PD) discovery, classification, current limit, and load disconnect detection.
The device supports single-supply operation, provides up to 70W to each port (Class 5 enabled), and still provides high-capacitance detection for legacy PDs.
Tomi Engdahl says:
Why the industry needs a PoE Logo Program
http://www.cablinginstall.com/articles/2014/08/poe-logo-program.html
It’s been more than 15 years since the IEEE 802.3™ Ethernet Working Group first started a project to provide “Power over Ethernet” as a way to use the existing network cabling to carry DC power for IP telephones and wireless access points (WAPs).
The first project, IEEE 802.3af™-2003, Data Terminal Equipment Power via the Media Dependent Interface (DTE Power via the MDI), was published in June of 2003. In 2009 an update to the original IEEE 802.3af-2003 standard, IEEE 802.3at-2009, was published; today they make up Clause 33 of IEEE 802.3-2012. The “PoE” standard(s) have been extremely successful, with tens of millions of powered devices (IP phones, WAP, security cameras and hundreds of new applications) shipped.
A key feature of the PoE standard was the ability to detect whether a device was capable of receiving remote power before the power was applied. Another key feature was setting specific limits for the voltage, current and amount of power delivered, and providing for power removal in the event of overloads or short-circuits. These features made PoE reliable and interoperable.
Two alternatives were allowed for powering a remote device: 1) power over the signal pairs (phantom power), and 2) power over the “idle” pairs.
Unfortunately, the success of PoE led to products that took shortcuts with the standard, or simply ignored it.
Many cheap “PoE injectors” appeared on the market. These units did not have any of the IEEE standardized features, and were frequently a power supply inside a box that interrupted the “idle” pairs and placed permanent voltage on them. n many cases this voltage was not the correct IEEE standardized voltage
Now look at the reviews and read the comments. See how many people are confused and unhappy because they bought products that said “Power over Ethernet,” but don’t work when connected together—or worse, did actual damage. The problem is not limited to consumers; many of these power injectors are sold through IT equipment dealers.
So what’s to be done? Education, of course, is a first step.
Certification and a logo program could bring this era of frustration and confusion under control.
Tomi Engdahl says:
LTC Design Note: Active bridge rectifiers reduce heat dissipation within PoE security cameras
http://www.edn.com/design/power-management/4436706/LTC-Design-Note–Active-bridge-rectifiers-reduce-heat-dissipation-within-PoE-security-cameras?elq=c709950993f34ee98f6b9230e47519eb&elqCampaignId=20013
LT4320 combined with low channel resistance MOSFETs results in a 20mV drop across each ideal diode bridge MOSFET. This produces an input at the isolated supply of 8.96V (9V – 2 • 20mV). The higher input voltage drops the required input current to only 2.9A (26W/8.96V) versus the original 3.5A.
Tomi Engdahl says:
Testing copper cabling for PoE presence, preparedness
http://www.cablinginstall.com/articles/print/volume-22/issue-11/features/installation/testing-copper-cabling-for-poe-presence-preparedness.html?cmpid=EnlContractorNovember132014
Testing for the presence of power sourcing equipment can be accomplished easily, but determining a cabling system’s ability to carry DC power and successfully transmit data is more challenging.
The Institute of Electrical and Electronics Engineers (IEEE; http://www.ieee.org) published its 802.3af standard-commonly referred to as Power over Ethernet (PoE)-in 2003. In 2009 the IEEE published 802.3at, which is commonly referred to as PoE Plus. While industry groups drum up support for the establishment of an official program to recognize standard-compliant and standard-friendly PoE devices (see “Why the industry needs a PoE Logo Program,” October 2014, p. 6), there is little debate about the proliferation of PoE. Claims that tens of millions of PoE powered devices (PDs) have shipped since IEEE 802.3af was ratified are widely made and accepted. Advocates of the technology make the claim that the 8-position, 8-contact (8P8C) RJ-45 jack is the global power outlet, enabling certain PDs around the world to receive direct current (DC) via power sourcing equipment (PSE) through the familiar interface-unlike the interface for alternating current (AC) power, which as world travelers are painfully aware, requires the use of country-specific adapters.
The delivery of PoE can come in the form of endspan or midspan. In either scenario, the existence of DC power on the line is a reality. And in the early days of PoE, that was a potentially perilous situation when a cabling installer or technician plugged a test device into a port. Plugging a tester into a PoE-enabled port prompted the PSE to engage the device on the other end to detect whether or not it would accept PoE; that engagement was enough to damage some testers’ circuitry.
Generations of test equipment that have been manufactured in the decade-plus since those first painful discoveries were made have done more than just protect against a PoE-enabled port damaging the tester.
The product line’s VDV Pro incorporates what the company describes as “intelligent technology” that “lets the unit know if it has been plugged into an outlet where potentially damaging voltages are present … By detecting the presence of voltage and checking polarity, the VDV II Pro quickly determines which type of media service is running over the cable, such as ISDN, PBX and PoE, resulting in faster fault diagnosis.”
The industry has progressed to a point at which detecting the presence of PoE on a copper cabling line is well understood and fairly easily accomplished. The industry, however, likely is just beginning to face the challenges associated with determining the ability of an installed twisted-pair cabling circuit to capably handle next-generation powering technologies-and the extent to which handheld cabling testers can help in that determination.
Within standards-making realms, and as we have reported in the past, the IEEE has established a P802.3bt 4-Pair Power over Ethernet Task Force. According to a recent “Standards Advisor” document published by CommScope (www.commscope.com), the task force adopted a timeline with expected publication date in early 2017.
DC resistance unbalance is an electrical-performance characteristic of twisted-pair copper cabling that is specified in some TIA cabling standards but not others. Specifically, certain DC resistance unbalance performance levels are required in component standards-meaning the performance levels must be met by manufacturers of twisted-pair cable. But no such performance levels are included in the specifications for testing installed twisted-pair cabling systems-meaning they are not required when systems are tested in the field.
Fluke Networks has been voicing concern over this issue for several months. The company recently published a white paper titled “DC Resistance Unbalance Testing: Easy, Low-Cost Insurance for Your PoE Systems.” That document explains that DC resistance unbalance becomes a factor when PoE is deployed via Alternative A, in which power and data are delivered over a cable’s pairs 2 and 3. In this scenario, “the power is transmitted over the data pairs by applying a common-mode voltage,” Fluke Networks says. “Power is received and returned using the center tap of a PD’s transformer, which splits the current between each conductor of the pair. When the resistance of each wire in the pair is equal, the DC resistance unbalance (the difference between two conductors) is at zero, current is split evenly, and common-mode current is achieved.
“While devices can tolerate some DC resistance unbalance, too much unbalance causes the potential for saturation of the transformer. This can ultimately distort the waveform of Ethernet data signals, causing bit errors, retransmits and even non-functioning data links.”
Fluke Networks’ DSX-5000 CableAnalyzer can test DC resistance unbalance, even though the characteristic currently is not required by field-test specifications.
“The ability to deliver a certain amount of power is dependent on the total DC loop resistance of a specific length of cable. DC loop resistance is calculated as the sum of the DC resistance of two conductors in a pair. According to IEEE standards, the channel loop resistance of a pair shall be 25 Ohms or less while permanent DC loop resistance shall be 21 Ohms or less.” The IEEE also addresses DC resistance unbalance: “IEEE 802.3-2012 specifies a maximum DC resistance unbalance of 3 percent between conductors, meaning that the difference in DC resistance between two conductors is no more than 3 percent of the total DC loop resistance of a pair.”
Will DC resistance unbalance make its way into an upcoming TIA or ISO/IEC cabling-test specification?
Tomi Engdahl says:
LXI + PoE: Essential Design Considerations
http://www.edn.com/design/pc-board/4437666/LXI—PoE–Essential-Design-Considerations?_mc=NL_EDN_EDT_pcbdesigncenter_20141124&cid=NL_EDN_EDT_pcbdesigncenter_20141124&elq=e595151f2eff48d39a93d9de73055467&elqCampaignId=20320
LXI is a standard for instrumentation controlled by Ethernet. Once the LXI device is connected to the LAN infrastructure of an organization, the device can be remotely controlled from anywhere on the network, and even offsite through a virtual private network [1]. In terms of physical connection, LXI devices must be able to achieve a data rate of 100Mbps during communication with its link partner, which is compliant with the specification of IEEE 802.3 Type 100BASE-TX [2].
On the other hand, PoE is the implementation of LAN switching infrastructure (i.e., power sourcing equipment or PSE) to provide power (i.e., 48Vdc) to the device connected to it, which means that PoE devices (PDs) are bus powered by PSE through LAN cable
The first essential task is to select a DC-DC converter compliant with IEEE 802.3at standard. This DC-DC converter steps down the 48Vdc supplied by PSE to lower power rails needed by the subsystems of the PD.
The designer is required to configure the PoE DC-DC converter based on the power loaded by the PD as categorized
The second key consideration for LXI PoE devices is transient voltage suppression (TVS) protection, where the TVS diode is placed as close as possible to the Ethernet RJ45 connector of the device
However, TVS diode with low parasitic capacitance (i.e., below 1.5pF) shall be chosen for protection of the PD.
Electrical isolation of 1500V is another key requirement, as specified in IEC 60950-1:2001 [5]. The RJ45 connector shall have a minimum clearance of 4mm to other circuitry of the PD. Besides that, DC-DC converter and RJ45 connector with 1500V isolation and Ethernet isolation transformer shall be used in PD.
The RJ45 connector with integrated EMI filter shall be applied in PD.
Upon hardware design completion, the prototype shall pass the LAN 100Base-TX PHY Compliance Test
Tomi Engdahl says:
Book Review: Power over Ethernet Interoperability
http://www.edn.com/design/power-management/4437769/Book-Review–Power-over-Ethernet-Interoperability
Power over Ethernet (PoE) was a solution to a problem in Voice over Internet Protocol (VoIP) systems.
Around 2001/2 IP Phone manufacturers and Wireless Access Point suppliers began to use this technique instead of the local 110V power. This is when the IEEE stepped in when the IEEE 802.3 Ethernet Committee gave the task of POE to a working subcommittee named IEEE 802.3af who released the first standard in 2003 at 15.4 W per link.
Then came PoE+ with 25.5W DC on the IEEE802.3at standard.
Fast-forward to 2013, the IEEE sets up a new study group to investigate the feasibility of standardizing 4-pair Power over Ethernet. This IEEE 802.3TM Ethernet Study Group is considering the 4-pair to enhance efficiency and supply more than 25.5 W of power to IP phones, access points, IPTV, Industrial Ethernet and more. The 4-pair approach would increase efficiency by lowering channel resistance.
An insightful technical treatment of Power over Ethernet along with a more extensive history taking us back 200 years is artfully covered in Chapter 1 of Sanjaya Maniktala’s book entitled Power over Ethernet Interoperability.
The second part of the book delves into pulse/data transformers, Isolation, PCB Design and Safety.
All of these tutorials have the common thread of interoperability and backwards compatibility ingrained.
Tomi Engdahl says:
IEEE to adopt HDBase-T, standardizing UHD transmission over Category 6 cabling
http://www.cablinginstall.com/articles/2015/01/ieee-1911-hdbaset-category-6-cabling.html
The Institute of Electrical and Electronics Engineers (IEEE), along with the HDBase-T Alliance, jointly announced that the IEEE Standards Association Standards Board approved the HDBase-T Specifications 1.1.0 and 2.0 as part of the IEEE’s standards portfolio. The HDBase-T standard will become IEEE 1911 standard once the adoption process is complete.
“HDBase-T is a successful technology for long-distance ultra-high-definition distribution of digital media today, with hundreds of HDBase-T products currently commercialized,”
“HDBase-T enables all-in-one transmission of ultra-high-definition video through a single 100-m/328-ft Category 6 cable,” the announcement explained, “delivering uncompressed 4K video, audio, USB, Ethernet, control signals, and up to 100 watts of power. HDBase-T simplifies cabling, enhances ease-of-use, and accelerates deployment of ultra-high-definition connectivity solutions. The cost-effective LAN infrastructure and power transmission support also help reduce and simplify installation and electrical costs.”
HDBaseT Alliance now offering 2 programs approved for InfoComm certification
http://www.cablinginstall.com/articles/2015/01/hdbaset-infocomm-rus.html
The HDBaseT Alliance, the cross-industry group tasked with promoting and advancing the HDBaseT standard, announced that it has been named an official InfoComm International Renewal Unit (RU) Provider. According to a press release, this will allow the more than 9,000 professionals holding InfoComm International’s Certified Technology Specialist credential to earn renewal units towards their certification by completing the HDBaseT Alliance’s Installer Expert education programs.
Tomi Engdahl says:
Tester checks RJ45 ports for PoE
http://www.cablinginstall.com/articles/2015/04/poe-bug-rj45-tester.html
Triplett recently added the PoE-Bug to its portfolio of test and measurement equipment. “The PoE-Bug tests RJ45 Ethernet ports for the presence of end- or midspan DC power,” explained Spencer Craig, director of product management for Triplett, “enabling installers and repairmen to preempt damage to their expensive equipment that could be caused by PoE.”
“a must-have tool for IP camera installers, enabling them to align and focus an IP camera from any convenient terminus along the data cable.”
Tomi Engdahl says:
PoE PSE Type 2 (30W) IEEE 802.3at Fully Autonomous Quad Port Solution
http://www.ti.com/tool/TIDA-00290?CMP=AFC-conv_eeWebRefDes
A fully autonomous IEEE802.3at, Type 2 (30W) Power-over-Ethernet (PoE) 4 Port Power Sourcing Equipment (PSE) solution. An additional configuration of two non-standard, high power ports (<60W) is provided. Both configurations support Gigabit Ethernet data pass through in 1000BASE-T ports.
This reference design is made up of two boards: Motherboard (TPS23861EVM-612) and Daughter board (TPS23861EVM-613). The daughter board features two TPS23861 IEEE 802.3at PoE PSE controller devices. The motherboard provides a multi-port base platform interface for the daughter board. Additionally, the motherboard provides interfaces for two optional boards: MSP-EXP430G2 LaunchPad™ (if custom Power Management programmability is desired) and USB-TO-GPIO Interface Adapter (if PC GUI based Power Management configuration is desired).
Tomi Engdahl says:
Standards:
PoE (IEEE 802.3f and IEEE 802.3at Type 1): 350 mA over 2 pairs = 12.94W (standard 2003)
PoE+ (IEEE 802.3at Type 2): 600 mA over 2 pairs = 25.5W (standard 2009)
PoE++ (proposed 802.3bt Type 3): 600 mA over 4 pairs = 49W (expected 2016-2017)
POE++ (proposed 802.3bt Type 4): 1000 mA over 4 pairs = 96W (expected 2016-2017)
Non-standard:
Cisco UPOE: 600 mA over 4 pairs = 60W
HDBase-T: 1000 mA over 4 pairs = 96W
If you plan to run PoE++, Category 6A is recommended. (category 5e and 6 runs should be assembled in bundles less than 100 cables if plan to be used to keep cable heating reasonable)
Arching or sparking can occur at high powers when plug is removed from the jack, they can damage jack or plug causing problems with data transfer. Connectors should meet IEC 60512-9-3 and IEC 60512-99-001 to ensure that arching does not damage critical plug-and-jack meeting point.
Leviton recommends using connectors with 50 micrometer cold planted tines (as specified by TIA standards). High quality connectors are essential for reliable operation in the long run.
Source:
http://digital.cablinginstall.com/cablinginstall/201506?sub_id=x6KJfBQa8ZsK&u1=DA0615&folio=11#pg16
Tomi Engdahl says:
PoE and other technologies are pushing powered-device wattages ever-higher
http://www.cablinginstall.com/articles/print/volume-23/issue-6/features/design/poe-and-other-technologies-are-pushing-powered-device-wattages-ever-higher.html
To date, the Institute of Electrical and Electronics Engineers (IEEE; http://www.ieee.org) has published two sets of specifications defining these capabilities. IEEE 802.3af (commonly called simply “PoE”) specifies the generation of up to 15.4 watts of power, with 12.9 watts delivered to the powered device (PD). And IEEE 802.3at (commonly called “PoE Plus,”) specifies the generation of up to 34.2 watts of power, with 25.5 watts delivered to the PD.
Ty Estes, director of marketing at Omnitron Systems Technology Inc. (www.omnitron-systems.com), explained, “The IEEE standard for 60W, also known as PoE++, is currently in development with the IEEE 802.3bt Type 3 Work Group, and is projected to be ratified in early 2017. In lieu of a 60W PoE standard, equipment manufacturers have doubled the 802.3at PoE+ capability on four pairs, and powered all eight pairs to achieve 60 watts.”
n 2011, Cisco (www.cisco.com) debuted its Universal Power over Ethernet (UPOE) system, which delivers 60 W to PDs. At the time of that announcement, Cisco’s Catalyst 4500E switch was the infrastructure that housed the 60-watt UPOE capability.
In 2011, the same year Cisco introduced UPOE, the HDBase-T Alliance (www.hdbaset.org) released the Power over HDBase-T (PoH) specification, which defines the delivery of up to 100 watts of power over a single cable, up to 100 meters.
As Estes mentioned, IEEE 802.3bt is under development. Within IEEE nomenclature, the 802.3af specification is known at “Type 1″ PoE, and 802.3at is known as “Type 2.” The current effort, 802.3bt, is likely to include a “Type 3″ and “Type 4″ PoE. Type 3 will specify a current level up to 600 milliAmps (mA) and 49 watts at the powered device, while Type 4 will specify a 1,000-milliAmp (1 Amp) current level and 96 watts at the powered device.
Among other topics, Straka addressed the extent to which heat rise within cable bundles could have deleterious effects on cabling system performance when those cables are carrying 100-watt PoE. Straka’s presentation noted, “Cable temperature matters because some temperature rise will increase cable insertion loss and may create bit errors; extreme temperature increase above the cable operating range can damage the cable.” Cable manufacturers, he noted, will provide users with information about the maximum bundle size that can meet the 15-degree temperature rise limit recommended in the TIA TSB-184 document, “Guidelines for Supporting Power Delivery Over Balanced Twisted-Pair Cabling.” Straka stated that the equation that should be used when planning for higher-power PoE is: cable temperature rating is less than or equal to the ambient temperature plus 15.
Tomi Engdahl says:
R&M educates on 4-pair Power over Ethernet (4PPoE)
http://www.cablinginstall.com/articles/2015/09/%72%6d-4ppoe-resources.html
Reichle & De-Massari (R&M), the Swiss developer and provider of cabling systems for high-end network infrastructures, is preparing planners and installers for the introduction of 4-pair Power over Ethernet (4PPoE) through the release of a new white paper, and with the launch of a specially developed PoE calculator.
The company notes that the new generation of power supply via local data networks (remote powering) should enable a supply of up to 100 Watts, which is four to five times greater than the current rate. The corresponding standard IEEE 802.3bt is currently in progress. 4P PoE allows more powerful terminal equipment to be supplied with energy via network cables; parallel power cabling is therefore no longer required. However, twisted-pair copper cables heat up during the supply process, leading to an increase in attenuation. This must be taken into account from the very beginning of a cabling project, which in turn poses new challenges when installing data networks.
R&M notes that the consequence of using 4PPoE is that every twisted pair in the network cabling has a current of between 650 and 1100 mA, depending on its power. This is a significant increase in load compared to pure data transfer. Due to physical losses, the cables and cable bundles heat up as a result of the energy transfer. According to R&M, a long-term temperature increase of 10ºC can halve the expected service life of the cable, due to the increased aging of the material. This temperature increase must also be limited for fire and occupational safety reasons.
Higher temperatures increase the copper resistance and the attenuation of the signal transmission, which reduces the potential length of a link. The cable temperature increases resulting from the energy transfer can increase the attenuation of a cable to such an extent that data transmission becomes impossible.
R&M also advises the use of modules and plugs with insulation displacement technology; this technology creates stable connections between the cables and connecting contacts that are similar to soldering joints. The widely distributed piercing technology penetrates only the insulation of the copper cables and creates a loose contact, which with live connections may in the worst case cause a fire.
The company adds that another problem may arise when using Power over Ethernet, if contacts are damaged by small arcs when disconnecting while live. When the contact breaks, a spark is created that at high transmission powers can destroy part of the contact. If this happens in the contact area of the connection, the transmission properties may be permanently impaired. R&M recommends the use of plug connectors and connection modules that are designed to ensure a sufficient distance between the breaking point and the nominal contact area.
Tomi Engdahl says:
General Cable’s GenSPEED products first to achieve UL’s LP listing for high-power PoE products
http://www.cablinginstall.com/articles/2015/10/gc-ul-lp-poe.html
General Cable (NYSE: BGC) announced that its GenSPEED brand data communications cables are the first in the industry to achieve the Underwriters Laboratories (UL) LP listing for efficient operation in high-power Power over Ethernet (PoE) applications.
The company notes that, “over the past decade, PoE has become a viable powering option for a wide range of applications. Anticipating future standards, device manufacturers are pushing the envelope and designing more sophisticated equipment that demands increased power.”
General Cable adds that UL’s new LP listing, which stands for Limited Power, provides a simple way to ensure installations are future-proofed against ever-increasing PoE standards, and not susceptible to performance issues caused by heat generation. The listing accounts for large bundle sizes, high ambient temperatures and other issues related to environmental effects such as enclosed spaces or conduits.
The new LP listing is denoted as a suffix and is followed by the ampacity rating of the particular cable.
GenSPEED 6 Category 6 (Plenum) – UL Listed CMP-LP (0.5A) supporting up to 100 watts
GenSPEED Brand’s EfficienC Max Category 6 (Plenum) – UL Listed CMP-LP (0.6A) supporting up to 120 watts
GenSPEED 10 MTP Thin-Profile Category 6A featuring EfficienC Max technology (Plenum) – UL Listed CMP-LP (0.7A) supporting up to 140 watts
Tomi Engdahl says:
Power over Ethernet (PoE) is a common way to reduce installation costs and time by allowing power and data onto a single twisted-pair cable. As the ubiquitous nature of Ethernet has grown, an increasing number of items are being networked together. These new items, such as digital signage, next generation wireless access points, nurse call stations, and thin clients, have power needs beyond the existing PoE+ standards. The industry has recognized this need, and has begun to develop PoE++ equipment that will supply 51 to 71 watts.
Source: http://www.cablinginstall.com/whitepapers/2015/11/power-over-ethernetwith-panduit-copper-cabling.html?cmpid=EnlCIMCablingNewsNovember232015&eid=289644432&bid=1240370
Tomi Engdahl says:
High-power PoE considerations: What you need to know
http://www.cablinginstall.com/articles/2015/11/high-power-poe-considerations.html?cmpid=EnlCIMCablingNewsNovember232015&eid=289644432&bid=1240370
Power over Ethernet (PoE) technology has been quietly gaining traction in the market ever since its launch in 2003, especially in Voice over Internet Protocol (VoIP) telephony and IP surveillance cameras. Today’s PoE landscape has effectively split into two broad categories: The first being non-standard applications with higher power delivery capabilities, such as Cisco’s UPoE 60W and HDBaseT’s 100W; and the second, IEEE standards-compliant 24.5 W 802.3at.
These non-standard applications create a significant paradigm shift in PoE possibilities. Power delivery through 1000 mA per pair and beyond is looming on the horizon. Steps will be necessary to ensure continued compatibility with this rapidly changing environment. To address this, the Institute of Electrical and Electronics Engineers (IEEE) is actively working on 802.3bt with expectations of powering schemes up to a maximum of 100W. This standard is expected to be ratified in 2017.
High-Power PoE Considerations
When contemplating a major increase in power, there are many key considerations. In order to go from a four-pair 60-watt output to a 100-watt output the current load changes from 600mA/pair to 1000mA/pair when the voltage of the power sourcing equipment (PSE) is kept at 50 volts. At such a drastic current capacity change, issues such as heat generation, power losses and safety protocols at the equipment end need to be studied. Heat generation, in particular, can be a serious issue for cables
Due to concerns about increased temperature rise, IEEE commissioned the Telecommunications Industry Association (TIA) to not only define expectations and details of the new PoE system, but also peak operating parameters and equipment requirements. The excess heat generated from cabling systems (not designed for the increased power consumption) can cause insulation and cabling heat-aging degradation as well as data transmission attenuation issues.
By assuming a 45°C maximum ambient temperature and a generalized cable operating rating of 60°C, they allowed for 15 degrees of heat rise for durability and effective data cabling use.
Category cabling option and heat rise
The conventional recommendation of PoE systems is that increased power will relate to increased category cabling. For example in 802.3at PoE+, category 5e cabling is the most basic construction, which provides sufficient conductivity without heat generation issues, therefore it became the minimum requirement. The same recommendation by TIA and the IEEE task force can then be expected with 802.3bt with the specified 600mA/pair maximum. The reduced heat generation of higher category cables is inferred mostly from the more stringent attenuation requirements of higher category cabling, causing cable manufacturers to increase conductor size. For example, a typical category 5e cable is constructed with 24 AWG conductors, while typical category 6A has 23 AWG conductors. However, now that 1000mA/pair is a real possibility, it will redefine what is acceptable for PoE between 60 and 100 watts.
It is quite clear that heat generation becomes a real issue in many of the most common cable constructions installed (or available) today. However, it is not an ideal assumption to use category designation as a PoE classification rating, because the majority of the heat generated from running amperage is due to conductor size or the presence of a shield.
Currently, in applications where higher power usage is expected in excess of 50 watts, yet higher data transmission rates are not required, there are few, if any, options. To appropriately address the increased temperature rise one could be confined to using category 6A or category 6A F/UTP. The limiting factor of many devices, especially IP cameras, nurse call systems, building management controls and point-of-sale is power consumption, not data. This places a difficulty on premise designers to justify the use of higher category cabling or the need to pull a power source onto a location.
Specifically designed with larger conductors, these EfficienC Max cables offer reduced resistances, which directly reduces the amount of heat generated within a current-carrying cable.
There are real benefits to using specially designed PoE cabling with properties such as larger, lower-gauge conductors and higher temperature cable ratings for the majority of PoE applications. Aside from having confidence that the cable will withstand higher temperature operations and generate lower temperatures, energy savings and efficiency are also considerations when deploying a large scale PoE infrastructure.
Tomi Engdahl says:
Cisco, Philips teaming up to offer connected, PoE-powered LED lighting
http://www.cablinginstall.com/articles/2015/12/cisco-philips-poe-powered-led-lighting.html?cmpid=EnlCIMCablingNewsJanuary42016&eid=289644432&bid=1265815
Cisco and lighting giant Philips recently announced their strategic alliance, through which the companies will co-market and co-sell Cisco’s Power over Ethernet-enabled switches and Philips’ PoE-powered LED lighting. When announcing the alliance, the companies said, “Lighting is everywhere, making it one of the easiest ways to bring the Internet of Things to office buildings. Light points in the Philips system, equipped with sensors and software applications, can be connected using Cisco technologies. This lighting network creates a pathway for information and helps enable new services.”
“Our alliance has two of the world’s biggest and trusted lighting and connectivity brands working together to bring the Internet of Things to life in offices and commercial buildings across the world,”
The companies stated that lighting typically is responsible for 40 percent of a building’s electricity use, and their joint technology offering can enable building operators to save nearly 80 percent in combined energy costs and building-maintenance costs.
“To make offices more comfortable, office workers can personalize and adjust LED lighting to their preferences and tasks,” the companies explained. “For mobile access, office workers can use a smartphone app to access other building services through a communications network.
“Lighting is a logical first step to bringing IoT to enterprises worldwide,” they added. “Equipped with sensors, connected lighting becomes intelligent to sense and measure power. For example, occupancy sensors in the system can provide information on space utilization to help reduce costs.”
The two companies teamed up when Cisco installed a Philips PoE-powered LED lighting system at Cisco’s Canadian headquarters at WaterPark Place in Toronto.
Tomi Engdahl says:
PowerWise Fiber combines PoE support and the distance of singlemode fiber
http://www.cablinginstall.com/articles/2016/02/superior-essex-powerwise-singlemode-fiber.html?cmpid=Enl_CIM_CablingNews_February82016&eid=289644432&bid=1303591
Superior Essex recently introduced PowerWise Fiber, which the company described as “a premises optical fiber cable coupled with copper conductors to support Power over Ethernet applications, including those with distances that exceed the standard 100 meters provided by category cables.” It cited several smart-building applications—including Nest, intelligent LED lighting and security systems—as appropriate uses for PowerWise Fiber’s ability to support device power as well as control through a single cabling system. “With the launch of this cable, Superior Essex now offers a complete Power over Ethernet cabling solution, with PowerWise Cat 5e+ 4-pair PoE cable powering and controlling devices at distances of up to 100 meters, and PowerWise Fiber cable supporting additional power and data transmission over greater lengths throughout an environment,” the company added.
The PowerWise Fiber cable comprises two, 2-mm bend-resistant G.657.B3 singlemode fiber simplex interconnect cables and two stranded 16-AWG copper conductors.
“Our customers required a small, flexible and durable cable for applications that exceeded the 100-meter reach limitation of Power over Ethernet and twisted-pair category cables. We designed this composite power and fiber cable especially for security camera applications where the reach often exceeds 100 meters. In addition, using G.657.B3 singlemode fiber assures that the signal will not be attenuated even with bend radii as small as 5 mm.”
Tomi Engdahl says:
UNH-IOL, Ethernet Alliance gear up for PoE equipment plugfest
http://www.cablinginstall.com/articles/2016/02/unh-ea-plugfest.html?cmpid=Enl_CIM_CablingNews_February222016
The University of New Hampshire InterOperability Laboratory (UNH-IOL), an independent provider of broad-based testing and standards conformance services for the networking industry, announced that it will be hosting the latest Ethernet Alliance Power over Ethernet (PoE) interoperability test event, scheduled for March 29 – 31, at the UNH-IOL’s new laboratory in Durham, NH. The multi-vendor plugfest for Ethernet Alliance members will bring together a diverse array of equipment and technologies to test PoE interoperability, as well as conformance with IEEE 802.3 specifications.
The three-day testing event will focus on demonstrating technology and equipment compliance with IEEE 802.3 PoE standards.
Tomi Engdahl says:
PoE mode A (share 10BASE-T and 100BASE-TX tx/rx wires):
48 V out on pins 1 and 2
48 V return on pins 3 and 6
PoE mode B (use 10BASE-T and 100BASE-TX fee pairs):
48 V out on pins 4 and 5
48 V return on pins 7 and 8
1000BASE-T uses all four cable pairs for simultaneous transmission in both directions
Source: https://en.wikipedia.org/wiki/Ethernet_physical_layer
Tomi Engdahl says:
Ethernet Alliance Plugfest confirms 100% interoperability of IEEE 802.3 PoE products under stress conditions
http://www.cablinginstall.com/articles/2016/09/ea-poe-confirm.html
Held March 25-31, 2016, at UNH-IOL’s state-of-the-art lab, the Ethernet Alliance’s interoperability test event attracted a range of equipment and technology vendors. Their devices were tested in accordance with two previously released IEEE 802.3 PoE specifications, IEEE 802.3af 1 and IEEE 802.3at 2, against a variety of scenarios, including increased stress conditions.
“The plugfest showed that there is clearly market enthusiasm for standards-based PoE interoperability,”
The event demonstrated IEEE 802.3-based PoE interoperability among devices from Brocade, Hewlett Packard Enterprise, Linear Technology, Microsemi, and Texas Instruments. All product combinations were shown to interoperate “over the worst-case Cat 5e cabling,” reports the Ethernet Alliance. In addition, all tested devices were shown to pass 99 percent of test cases related to standards conformance.
http://www.ethernetalliance.org/
Tomi Engdahl says:
802.3bt controller supplies 71 W to PDs
http://www.edn.com/electronics-products/other/4442726/802-3bt-controller-supplies-71-W-to-PDs?_mc=NL_EDN_EDT_EDN_today_20160922&cid=NL_EDN_EDT_EDN_today_20160922&elqTrackId=671666697d50489a87986cbf6db49b91&elq=2fafbca6168c428da1ed96e55806b383&elqaid=33985&elqat=1&elqCampaignId=29708
The LT4295 PD (powered device) interface controller from Linear Technology increases the power budget of the IEEE 802.3at PoE (Power over Ethernet) standard from 25.5 W to 71 W to enable new applications. Compliant with the IEEE 802.3bt (Draft 2.0) standard, the LT4295 not only offers up to 71 W of delivered power, but also supports 10 Gigabit Ethernet (10GBASE-T) and maintains backward compatibility with older PoE equipment.
The controller supports new 802.3bt features, including all additional PD classes (5, 6, 7, and 8), additional PD types (Type 3 and 4), and 5-event classification. It integrates an isolated switching regulator controller
LT4295 comes in a 4×5-mm, 28-lead QFN package. Prices start at $2.75 each in lots of 1000 units.
LT4295 – IEEE 802.3bt PD Interface with Forward/Flyback Controller
http://www.linear.com/product/lt4295
IEEE 802.3af/at/bt(Draft 2.0) Powered Device (PD) with Forward/Flyback Controller
Supports Up to 71 Watt PDs
5-Event Classification Sensing
Superior Surge Protection (100V Absolute Maximum)
Wide Junction Temperature Range (–40°C to 125°C)
>94% End-to-End Efficiency with LT4321 Ideal Bridge
Tomi Engdahl says:
5 V, 2.5 A Power Supply for Non-Isolated PoE
https://www.eeweb.com/project/design_library/5-v-2.5-a-power-supply-for-non-isolated-poe
To meet the increasing demands for non-isolated Power over Ethernet (PoE) power solutions, Maxim has developed innovative, non-isolated PoE powered device (PD) power solutions. Each design was tested for load and line regulation, as well as efficiency and transient performance. As with all Maxim reference designs, the BOM, schematics, layout files, and Gerber files are all available and may be downloaded from the Design Resources tab. In addition, boards are available for purchase. These boards feature a module architecture, with through-hole pins for immediate board placement and accelerated prototyping.
MAXREFDES98# combines the PD controller and the step down converter on a 14.0mm (0.55in) x 55.9mm (2.2in) board. The module accepts input voltages ranging from 36V to 57V, and provides an output voltage of 5V with current capacity of 2.5A.
Tomi Engdahl says:
Remote powering equals opportunity
http://www.cablinginstall.com/articles/print/volume-24/issue-10/departments/editorial/remote-powering-equals-opportunity.html
No fewer than five presentations made during the conference included remote powering as a significant focus, and in some cases it was the primary focus. I use the term “remote powering” here rather than Power over Ethernet or PoE, because I view remote powering as a superset of PoE. All PoE is remote powering, but not all remote powering is PoE. One of the most-discussed applications for remote powering nowadays is lighting.
Another reason I use the term “remote powering” rather than “PoE” is that despite the term’s widespread use in the industry and close association with the IEEE 802.3af and 802.3at specifications, as well as the forthcoming 802.3bt specifications, “Power over Ethernet” has not been trademarked by the IEEE. A device does not need to comply with the “af” or “at” specifications in order to carry the term.
Yet the term PoE proliferates just like the technology does. And that is why I believe remote powering, including 802.3af-, at-, and bt-compliant technologies, represent such an opportunity for you as cabling professionals.
Tomi Engdahl says:
AV cable recommendations for HDBaseT
http://www.cablinginstall.com/articles/2016/10/cable-for-hdbaset.html?cmpid=enl_CIM_CablingInstallationMaintenanceDataCenterNewsletter_2016-10-31&[email protected]&eid=289644432&bid=1573049
Large-format displays are changing the digital-media/digital-display landscape. Increasing display size for audiences in classrooms, hospitals, hotels, and the enterprise is driving the need for higher-resolution, moving beyond today’s high of 1080p. Ultra-high-definition video with 4K and even 8K resolution is regarded as the next standard, with 4K delivering 2160p format at 3840×2160 pixel density.
HDMI cable alone is not an ideal solution for transmitting higher-resolution signals over longer distances. Long HDMI cables are heavy, inflexible, expensive and difficult to pull. Because of the large connectors, these cables are unfeasible for retrofit or upgrade projects in conduit applications.
Preterminated multi-conductor runners with active and passive wallplates, another method of AV connectivity, have many of the same issues when delivering high-resolution signals over long distances.
Overall, HDMI and muli-conductor runner solutions, while good for shorter lengths, are more expensive and troublesome when used over longer distances, especially when plenum-rated cable is required. For higher resolution over longer distances, HDBaseT technology that transmits HDMI signals over category-rated cable delivers the resolution needed for the distance required while minimizing costs, maintaining reliability, and making installation fast and easy.
HDBaseT is widely becoming adopted by installers as a reliable, plug-and-play HDMI extension method. With an HDBaseT AV Signal Extender you are able to turn a tested, certified datacom permanent link/channel into an IT/AV link/channel that is more reliable, flexible, and scalable than traditional HDMI cables or multi-conductor systems. And HDBaseT allows displays to be installed using the same materials and skills currently used for a LAN infrastructure, creating big opportunities and a new source of revenue for datacom installation experts.
When planning to deploy category-rated cable for an IT/AV link, it’s important to install the most appropriately rated cable for the performance desired. The HDBaseT Alliance specification lists Category 5e and Category 6 UTP cabling as supported media types. However, recent testing by Leviton revealed that Category 6A UTP cabling is the most ideal solution to support an IT/AV link.
Results:
Category 5e channels can carry HDBaseT 1.0 1080p signals in a point-to-point isolated channel
Category 5e channels do not support HDBaseT signals in high-density installations bundled with adjacent HDBaseT channels
When a Category 5e UTP channel is tested with one adjacent HDBaseT disturber, the HDBaseT extender attempts to connect, but never succeeds
Category 5e channels are not designed for 300-MHz signals and are not optimized for resistance to alien crosstalk
Testing with Category 6 UTP Cable
Results:
Even Category 6 UTP cable with increased margin over the ANSI/TIA standard is limited in carrying HDBaseT 1.0 signals when adjacent to other cables carrying HDBaseT signals
Category 6 channels are not designed for 300-MHz signals and are not optimized for resistance to alien crosstalk
Tomi Engdahl says:
TIA TSB-184-A standard, providing PoE cabling guidelines, in final balloting stage
http://www.cablinginstall.com/articles/2016/10/tia-tsb-184a-poe-cabling-guidelines.html?cmpid=enl_CIM_CablingInstallationMaintenanceDataCenterNewsletter_2016-10-31&[email protected]&eid=289644432&bid=1573049
The Telecommunications Industry Association (TIA) standards document that will provide recommendations for PoE cabling systems soon will be ready for publication. TIA TSB-184-A will officially be titled Guidelines for Supporting Power Delivery Over Balanced Twisted-Pair Cabling. It will be an update to the original TSB-184 document, which has the same title and was published in 2009.
TSB-184-A is in the standard-development stage called default balloting; the default ballot will close on December 2.
The document provides recommendations for the installation and management of twisted-pair cables that will support the supply of direct-current (DC) power to networked devices, in addition to carrying data to those devices. Of particular note, the recommendations will aim to minimize the temperature rise in groups or bundles of cables that support DC power delivery.
A late draft of TSB-184-A includes the following explanation: “When twisted-pair cabling is used to remotely power a device, the majority of the power entering the cable is successfully delivered to the device being powered; only a small percentage dissipated as heat in the cabling. This dissipation of power can cause the cabling to increase in temperature above the ambient temperature of the environment in which the cabling is installed.”
Tomi Engdahl says:
Your questions answered: Next-generation lighting: the emergence of PoE for lighting and controls
http://www.csemag.com/single-article/your-questions-answered-next-generation-lighting-the-emergence-of-poe-for-lighting-and-controls/282c886c5a796297125441df3854f522.html?OCVALIDATE&ocid=101781
Using Power over Ethernet (PoE) not only cuts installation and commissioning costs, but—more importantly—opens the door to endless building integration options that build upon the idea of intelligent or high-performance buildings.
Question: What is the 90 W standard distance limitation?
Casadonte: 100 meters
Question: What is the current technology maximum for a PoE wattage available on a given category cable for a lighting fixture?
Casadonte: A little over 100 W as the Cat-x will likely begin to overheat if pushed further. Expectations that new cable technology will be in place as the PoE standards grow.
Question: NFPA 70: National Electrical Code (NEC) requires complete separation of wiring for emergency lighting circuits. How do you configure your system to provide separation of normal power lighting from emergency?
Casadonte: A separate PoE switch and Cat-x cabling.
Question: Are the PoE lighting devices more energy efficient than their 120/277 V equivalents? That is comparing LED to LED.
Casadonte: About the same.
Tomi Engdahl says:
Automotive bus; 6Gbps duplex on UTP, by ST/Valens
http://www.edn-europe.com/news/automotive-bus-6gbps-duplex-utp-stvalens
Valens and STMicroelectronics are to, “join forces to revolutionize in-car connectivity”; their HDBaseT Automotive technology enables simultaneous transmissions of up to 6 Gbps of high-definition video & audio, USB, data, and power over a single twisted-pair cable.
Valens (Hod Hasharon, Israel) and STMicroelectronics have announced a collaboration to bring HDBaseT Automotive into the next-generation of connected cars. The highly efficient technology optimizes in-vehicle connectivity by enabling the transmission of reliable 6 Gbps high-throughput infotainment, road safety, and automotive-control content over a low-cost infrastructure with near-zero latency.
HDBaseT Automotive enables the tunneling of up to 6 Gbps of video, audio, data, USB and more, with native networking capabilities over a single unshielded twisted-pair (UTP) cable for up to 15m (50 ft). HDBaseT Automotive also allows for daisy-chaining and multistreaming, to simplify and optimize in-vehicle connectivity.
“We can see the potential of HDBaseT Automotive as a high-throughput, low-latency, low-cost technology.”
http://www.valens-automotive.com/?Automotive/
Valens founded the HDBaseT Alliance in 2010, driving the mass adoption of HDBaseT in the consumer electronics and pro-AV sector. In 2016, the Alliance’s Automotive Working Group was established to advance the development and adoption of HDBaseT Automotive technology,
Tomi Engdahl says:
A Cisco PoE LED lighting partner signs US distributor
http://www.ledsmagazine.com/articles/2016/11/a-cisco-poe-led-lighting-partner-signs-us-distributor.html?cmpid=EnlLEDsNovember92016&eid=289644432&bid=1583577
In another inroad for Internet-connected and controlled lighting, US computer and communications systems integrator CEC said it is now offering LED-based Power over Ethernet (PoE) lighting.
PoE lighting makes uses of Ethernet cables to furnish LED luminaires with electricity as well as with data, which is Ethernet’s mainstay use. The cables can handle the low voltages required by LEDs — which are low energy — and thus, say PoE supporters, can eliminate the need for certified electrical work in new buildings.
The same cables route data to the lights and thus enhance their control, allowing different levels of brightness, color temperature, and in some instances, color, via remote Internet control.
Digital SSL’s mega disruptor will be Power over Ethernet (MAGAZINE)
http://www.ledsmagazine.com/articles/print/volume-12/issue-11/features/networks-power/digital-ssl-s-mega-disruptor-will-be-power-over-ethernet-magazine.html
Power over Ethernet distributes DC power over inexpensive data cables instead of costly conventional lines, threatening utilities, electricians, and contracting firms, explains MARK HALPER. Meanwhile, the technology turns LED luminaires into data nodes, allowing IT companies to muscle into the lighting sector.
Are you ready for a rumble? The advent of Power over Ethernet (PoE) technology is setting up a heavyweight title fight between Big Lighting and Big Networking for control of future indoor commercial lighting products and infrastructure. Indeed, PoE can replace the AC electrical grid in buildings, deliver energy efficiency beyond what inherently efficient LEDs already offer, and enable networking for further savings and adaptive controls. It’s really no surprise that the evolution of smart solid-state lighting (SSL) has garnered the attention of companies such as networking and Ethernet stalwart Cisco. But even companies known traditionally for their lighting have begun to realize the potential of PoE — for example, Philips, with its involvement in a large PoE-based commercial project in Amsterdam
Consider that when teachers go for their information technology training at Miami-Dade County Public Schools, a big lesson immediately stares them in the face even if they don’t realize it: The ceiling lights that illuminate the classroom draw electricity from modern Ethernet data switches and cables instead of from a conventional 120V electrical grid.
What’s more, the same Ethernet doubles as an information conduit carrying instructions straight to the lights, turning them on and off, and making them shine at desired brightness levels, correlated color temperature (CCT), and color. It’s all linked into the same network that does all the other things a school IT system does — carrying emails, announcements, presentations, administrative instructions, coursework, and the like
The moral of the story: Miami-Dade is on the cusp of PoE LED lighting, a technology in its infancy, and one that many people believe will become the standard method of lighting buildings as it replaces expensive, electrician-reliant, century-old ways. “It’s the future,” said Debbie Karcher, Miami-Dade’s chief information officer. “I don’t know why it wouldn’t be.”
PoE takes advantage of two LED lighting attributes: low power requirements and affinity for digital connectivity and control. The world’s 120V and 240V AC electrical wires and all the cost, regulations, and infrastructure that go with them greatly exceed what LED lights need. LED luminaires contain electronics that knock those levels down, typically to 12V DC. Ethernet cable, which is already present in offices, safely carries lower DC voltages — which in turn do not require electricians and all their trappings.
The idea of using Ethernet as an electrical pathway is not new. A lot of data-connected office equipment such as phones and printers already use it, tapping into the same twin benefits of power and data that are set to take hold in lighting. For more than a decade, PoE has worked hand-in-glove with voice over IP (VoIP)
But while PoE may well be, as Karcher noted, lighting’s future, it is not yet its present. PoE lighting installations today are characterized either by a few vendor-driven showcase installations
For the concept to truly take off, more products and services must hit the market.
They include luminaires
Emerging products also include the Ethernet switches such as those that Cisco is refining with greater PoE capabilities and power capacity (Fig. 4). For Cisco, PoE lighting is vital to its overarching “Internet of Everything” strategy. Also part of the mix is software that helps tie it all together, provided by companies such as UK-based Philips spinoff amBX.
And while that all plays out, a good old “co-opetition” scenario is unfolding as conventional lighting companies like Philips go after a market that also keenly interests info tech giants such as Cisco and Google. The two sides will have to figure out how and when to collaborate or compete.
So far, Big Networking and Big Lighting seem to have a checkered relationship. Cisco is nowhere to be seen in Philips’ project at The Edge (as shown in Fig. 1), the largest publicly known PoE installation, where Philips provided not only the lighting but also supplied the Ethernet switches through either a third party or, according to one source, by custom building them. Likewise, Philips is not supplying the luminaires at the Cisco C-suite in San Jose. Those come from NuLEDs.
For instance, Philips has installed a PoE system across five floors at Cisco’s Canadian corporate headquarters at an office tower in Toronto, Canada.
Here’s what will really make LED office lighting take off
http://luxreview.com/article/2015/07/here-s-what-will-really-make-led-office-lighting-take-off
Tim Sluiter is one of the few lighting users in the world who can testify to the virtues of connecting both electricity and data to his building’s thousands of LED luminaires via information network cables. That’s because he’s one of the planet’s few such practitioners of ‘power over Ethernet’. Maybe even the only one.
Sluiter is the property manager for Deloitte at the consulting giant’s modern European headquarters
Not happy to simply reap the considerable energy-saving and maintenance benefits of low power, long-lasting LED lamps, Deloitte also designed power over Ethernet (PoE) for the 6,000 LED luminaires across the building’s 14 floors, eight of which Deloitte occupies.
While data collection is a huge driver in LED PoE systems, half the reason for implementing the technology is even more basic: LEDs run on low voltage and thus do not require conventional electrical mains cables that feed other equipment or even incandescent lighting.
The benefits can start with cost: by doubling up on the use of Ethernet cables, users can save a bundle in electrical wiring costs by eliminating more costly conventional mains wiring and installation. Jaques Letzelter, Philips office lighting segment leader, estimates that PoE slashes installation time by 50 per cent, and cuts overall installation costs by about 25 per cent.
There are tradeoffs, though. PoE lighting comes with its own upfront costs. LEDs, for instance, are still more expensive than conventional light sources. And wiring them to Ethernet is not free.
‘Of course you have to spend some extra money to do a really new thing and a new system,’ says Sluiter, who declines to say how much Deloitte spent on its PoE LED system at The Edge
Deloitte has established its LED luminaires as vital nodes in a building-wide information technology system that will monitor and react to conditions inside. The ‘computer with a roof’ cuts its own costs as it improves efficiencies on a variety of operations such as lighting, heating and cooling, office cleaning, and even room usage, which can be a challenge in a flexible ‘hot-desk’ environment
Realm of the senses
Each luminaire includes four sensors: one each for detecting light levels, temperature and occupancy (a motion sensor), plus an infrared sensor that serves as emergency control in the event of a power failure.
Those sensors provide the foundation for detecting things like exactly how much and when to crank up the heating or air conditioning, or when to turn the lights on or off or brighten or dim them. That, in turn, can lead to considerable savings as the lights switch off or the heating turns down in an unoccupied room or floor.
Deloitte also expects to save about 10 per cent on cleaning bills, because information that travels back through the Ethernet will tell facilities managers that a room remained unoccupied during the day and thus does not require attention.
But the sensors and the Ethernet are just part of the basket of goodies that puts Deloitte and The Edge on the vanguard of digital LED lighting technology. Employees can control the lights and the heating levels in their area using apps on their smartphones or tablet computers.
The system knows which lights to adjust because the phones are in constant contact with the LEDs via a fledgling technology known both as ‘visible light communication’ (VLC) and ‘indoor positioning’. VLC emits varying wavelengths of light picked up by a smartphone’s camera. Each luminaire emits its own specific wavelength. When a user commands a light, the system knows which lights are nearby, and thus which ones to adjust.
From Ethernet to VLC and back again
Sounds a little complicated, yet simple enough.
But it all gets a bit more complex because the phones do not connect directly back to the LEDs. Rather, when a user’s command leaves the smartphone, it travels via Wi-Fi to a nearby hub, which then routes the command to the building’s lighting or heating controls via the wired networked system. In the case of lighting, the command travels back to the nearby ceiling luminaires over Ethernet, thus completing the VLC-originated circle with a final PoE connection.
LED, VLC and PoE all wrapped up in one slick, ultra-digital, seamless to the user modern lighting system.
Tomi Engdahl says:
The Power over Ethernet lighting picture gets bigger
http://www.ledsmagazine.com/articles/2016/06/the-power-over-ethernet-lighting-picture-gets-bigger.html?cmpid=EnlLEDsNovember92016&eid=289644432&bid=1583577
A few weeks ago, LEDs Magazine reported that a Long Island data center is deploying Power over Ethernet (PoE) lighting, with hopes of cutting energy consumption 70% beyond what conventional energy-efficient LED illumination offers.
As we noted, the mindSHIFT Technologies data center has installed 452 new PoE luminaires plus PoE controls and software from Cree Inc., in a $160,000 project,
The moral of the story: The fledgling PoE lighting movement is busy enough to accommodate multiple vendors at one site.
As a quick refresher, PoE is one of several technologies that is ushering in the smart lighting movement, turning LED lamps and luminaires into nodes on information networks and connecting them to the Internet. Such intelligent networks give users far greater control of lighting levels, colors, and color temperatures. They also open the possibility of using lights to collect data on climate, occupancy, noise, air quality, and many other things, and to leverage that data for other purposes such as controlling heating and cooling, rearranging building layouts, or engaging customers.
PoE comes with the added benefit of cutting electrical cabling costs on new buildings, because the same Ethernet wires that carry data to the lights also carry the light’s electricity.
One of the leading proponents of PoE lighting is Cisco Systems, the networking equipment — and Ethernet — giant. It partnered with Cree at mindSHIFT in an early example of Cisco’s new “digital ceiling” initiative, which Cisco launched in February with 15 partners, a number that now stands at 23 including Cree, Philips, and other lighting vendors as well as companies from related automation and buildings industries, such as Johnson Controls.