High power PoE and HDBaseT

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 is fully backwards-compatible with the IEEE802.3at-2009 PoE specification. HDBaseT also does not infringe on any of the mandated PoE safety requirements.

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.

265 Comments

  1. Tomi Engdahl says:

    How ANSI/TIA-1179-A supports PoE LED lighting in healthcare
    https://www.cablinginstall.com/articles/2018/11/how-ansi-tia-1179-a-supports-poe-led-lighting-in-healthcare-belden-ron-tellas.html?cmpid=enl_cim_cim_data_center_newsletter_2018-11-12&pwhid=6b9badc08db25d04d04ee00b499089ffc280910702f8ef99951bdbdad3175f54dcae8b7ad9fa2c1f5697ffa19d05535df56b8dc1e6f75b7b6f6f8c7461ce0b24&eid=289644432&bid=2297054

    – Lighting systems that bring IT and lighting together are starting to permeate smart buildings. In the past few years, PoE LED lighting has hit the scene. In this type of system, Ethernet cables are used to transmit low-voltage power along with data (data about surrounding lighting levels, occupancy levels, color tuning, etc.).

    Some of the recent changes to healthcare cabling standards are designed to better support technology like Building Automation Systems, which includes PoE LED lighting. ANSI/TIA-1179-A, the Healthcare Facility Telecommunications Infrastructure Standard, provides guidance for planning and installing structured cabling systems in healthcare facilities. It establishes performance and technical criteria for various cabling system configurations.

    The minimum for backbone and horizontal balanced, twisted-pair cabling is now Category 6A per ANSI/TIA-1179-A. This helps ensure futureproofing and the accommodation of higher bandwidth levels. Category 5e and Category 6 cables are no longer recognized.

    While all Category 6A cables must meet the same specifications,

    The right Category 6A cable achieves higher performance and faster speeds, maintains appropriate cable temperatures through enhanced thermal dissipation and supports emerging applications like next-generation WiFi, higher-power PoE and HDBaseT.

    Guidance for Network Elements

    MUTOAs and consolidation points (CPs) can now be used as additional network elements in work areas.

    MUTOAs are a convenient way to distribute the last few feet of horizontal cabling in spaces that require frequent reconfigurations or moves, adds and changes. Using a MUTOA allows horizontal cabling to remain intact when things change – like LED lighting fixtures being added, removed or relocated.

    A CP is an interconnection point within a horizontal cabling system; it requires an additional connection for each horizontal cable run. It can be useful when frequent reconfiguration occurs (but not frequently enough to need a MUTOA).

    Solutions to Make PoE LED Lighting Deployment Easier

    LP-rated cables are a solid option for deploying PoE LED lighting systems. They utilize insulating and jacketing material to handle higher temperatures, allowing them to be certified by UL as a cable that doesn’t exceed temperature ratings under certain conditions. This makes them ideal for applications that support higher-power IoT devices, like LED fixtures.

    In terms of connectivity, modular plug terminated link (MPTL) was recently approved for use by ANSI/TIA-568.2-D, the Balanced Twisted-Pair Telecommunications Cabling and Components Standard.

    Direct connect allows a horizontal cable run to connect directly to a device when it terminates on one end to an RJ45 plug. It’s now acceptable to connect a device – like an LED lighting fixture – in this fashion when deploying an outlet, faceplate and equipment cord isn’t practical. Direct Connect also improves power delivery efficiency since the horizontal cable (the largest gauge wire with lowest resistance in the channel) is able to directly connect to the end device.

    The Surprising Benefits of PoE Lighting in Healthcare
    https://www.belden.com/resources/knowledge/webinar/the-surprising-benefits-of-poe-lighting-in-healthcare

    Reply
  2. Tomi Engdahl says:

    How ANSI/TIA-1179-A supports PoE LED lighting in healthcare
    https://www.quantamagazine.org/new-proof-shows-infinite-curves-come-in-two-types-20181107/?utm_campaign=Email%20Newsletter&utm_source=hs_email&utm_medium=email&utm_content=67998689&_hsenc=p2ANqtz-_Cwq0fLoD-jlLVyuXFEZFJdyHPH8n8UIBoGJwEru4t76cDw4t118CIf2rQFfkwcuH-2ve6–jH_nVdu5bzh88E9iE_eaGHrQjfgxQL2a1lSwJhmhs&_hsmi=67998689

    The standard was updated last year – in August 2017 – to support efficient powering, ensure reliable cabling solutions, accommodate increasing bandwidth and IP applications, and improve productivity. The changes in ANSI/TIA-1179-A will help hospitals, assisted-living facilities and other healthcare buildings deploy PoE LED lighting successfully.

    Reply
  3. Tomi Engdahl says:

    Eliminating the blame game: How to test and certify your network for IoT readiness
    https://www.cablinginstall.com/articles/print/volume-26/issue-11/features/testing/eliminating-the-blame-game-how-to-test-and-certify-your-network-for-iot-readiness.html?cmpid=enl_cim_cim_data_center_newsletter_2018-12-03&pwhid=6b9badc08db25d04d04ee00b499089ffc280910702f8ef99951bdbdad3175f54dcae8b7ad9fa2c1f5697ffa19d05535df56b8dc1e6f75b7b6f6f8c7461ce0b24&eid=289644432&bid=2315028

    You need more than ever from your test equipment in the age of IoT, PoE, and multiple link speeds.

    If the PoE powering malfunctions, a combination of one or more of the following reasons might be at play.

    The switch is not able to provide the required power (it could be faulty, over-provisioned, or over-specified).

    The PD is consuming more power than specification.

    The cable is dissipating more power than expected or specified, which could be due to high resistance, link length exceeding specs, or thermal stress in the cable bundle.

    Reply
  4. Tomi Engdahl says:

    Vital tips about wires, cabling
    https://www.csemag.com/articles/vital-tips-about-wires-cabling/

    Ethernet cable not only can be used to transmit data and communication, but also power for low-power-usage devices. This article discusses design considerations and relevant codes and standards.

    Power-limited circuits

    NEC Article 725 categorizes power-limited circuits into three classes: Class 1, Class 2, and Class 3.The power limitation for a Class 1 circuit is 1,000 VA (volt-amperes) and not more than 30 V.

    The power and voltage limitations for Class 2 and Class 3 circuits are defined in NEC Chapter 9, Tables 11(A) and 11(B). The volt-amperes allowed do not exceed 250 VA and have several other parameters based upon whether the system is ac or dc, whether overcurrent protection is required, and what the circuit voltage is (never exceeding 150 V).

    Power-limited cable classifications

    Class 2 and Class 3 cables have various power, location, and support requirements specific to their application. Power regulations are specified in NEC 840.160 regarding power-limited PoE systems. Any device requiring less than 60 W is typically unrestricted; however, once the 60-W threshold has been exceeded, the additional requirements of Article 725 govern the system. It is important to mention that Article 840.160 strictly avoids any discussion on power factor or harmonic content. However, because the category cables will only be carrying direct current, it is assumed that watts and volt-amperes are equal for the specified applications.

    Additional classifications dependent on location apply when dealing with applications in dedicated air ducts, plenums, risers, and general spaces and must be protected independently.

    Restricted areas, such as plenums and risers, have special requirements for code-allowable installations.

    For installations in spaces rated for environmental air recirculation, cables must be tested under NFPA 262: Standard Method of Test for Flame Travel and Smoke of Wires and Cables for Use in Air-Handling Spaces. This measures the flame’s travel distance and the optical density of smoke for insulated and/or jacketed electrical wires and cables and fiber-optic cables intended for installation in plenums and similar areas.

    Per NEC requirements, all CL2- and CL3- cables must be clearly labeled for location-appropriate installations and are appended with a location-specific letter to indicate acceptable practices.

    A common application for these cables is a Class 2 power supply operating at 24 V with a load of less than 100 VA, typically found in many LED lighting power supplies. Some advantages of a Class 2 cable system are the inherent safety factors in installation, maintenance, and operation. The limited voltage and power available prevent the initiation of fire as well as the risk of electrical shock.

    For PoE systems, the category cable is typically the chosen method of power delivery. These cables generally are supplied with between 22- and 26-AWG copper conductors in the twisted pairs. The small cross-sectional area of these wires inherently limits the current permitted to pass through the cables.

    The recent advancements in LED technology work in tandem with more capable cables to allow for larger systems to use this method of power delivery. It is also notable that in PoE circuits of more than 60 W, the ampacity determination of the conductor varies significantly from that of NEC Article 310. The number of bundled cables, size of the copper conductor, temperature rating, and conductor use are still the predominant factors, but they are scaled down for maximum ampacities up to 3 amps. Details are found in NEC 725.144.

    NEC 725.143 contains requirements for the support of conductors. This section states that Class 2 and Class 3 cables shall not be strapped, taped, or attached by any means to the exterior of a conduit or other raceway as a means of support.

    When determining the required ampacity of the cables, the higher-numbered category cables will generally provide a lower internal resistance; for example, Cat-5e is typically more resistive than Cat-6a.

    This metric is critical in preventing power losses across the communication channel. Joule heating is responsible for a majority of all power dissipation in resistive cables and can be detrimental to a communication circuit’s functionality. Every incremental increase in internal resistance provides equal incremental power losses in the system.

    the NEC recommends limiting voltage drop to an overall 5% from the point of service to the final outlet or device.

    In general, it is recommended to limit the voltage drop to 2% for feeders and 3% for final branch circuiting. For Ethernet category cables, this distance is limited to 100 m (328 ft), with 90 m (295 ft) allowed from the patch panel and 10 m (33 ft) from the wall jack to the device. When the powered device (PD) is attached to the power-sourcing equipment (PSE), the PD sends a signal to the PSE requesting the amount of power it requires to operate.

    At more than 300 ft, the camera’s operation may be compromised; however, devices such as injectors and fiber-optic media converters can extend the maximum distance of a system by hundreds of feet.

    Reply
  5. Tomi Engdahl says:

    Has PoE for lighting finally arrived?
    https://www.edn.com/electronics-blogs/led-diva/4461352/Has-PoE-for-lighting-finally-arrived-?utm_source=Aspencore&utm_medium=EDN&utm_campaign=social

    While power over Ethernet (PoE)-based LED lighting has been available for the past half-dozen years, there hasn’t been much attention devoted to this technology in the LED lighting industry until relatively recently. With the recent release of IEEE 802.3bt-2018 – IEEE Approved Draft Standard for Ethernet – Amendment 2: Power over Ethernet over 4 Pairs, that may be about to change.

    The IEEE 802.3bt standard, approved by the IEEE Standards Association Board on September 27, 2018, includes some significant enhancements for LED lighting systems. The main driver of this improvement is the specification for up to 90W of delivered power for cable lengths of up to 100m through the use of all four pairs of wires. This allows for daisy chaining of several luminaires, which can simplify the installation process.

    Data and power delivery to the luminaires is accomplished via the addition of a “node” mounted inside the luminaire housing and connected to the LED light engine power and dimming inputs. Depending upon the capabilities of the connected luminaire and its associated auxiliary devices, other functionality is handled by the node as well. Igor Inc’s node allows multiple devices to be connected to a PoE network.

    Due to the reduction in the number of AC-DC power conversions, PoE lighting systems can offer improved overall energy efficiency in comparison to traditional AC line voltage systems. Ethernet cable loss appears to be the main concern in terms of assessing total system power consumption

    NEMA/ANSI C137.3-2017 Minimum Requirements for Installation of Energy Efficient Power over Ethernet (PoE) Lighting Systems provides installation requirements. Specifically, the standard establishes the minimum wire gauges to limit average resistive line losses to less than 5% of the total power delivered assuming a 50m average cable length.

    Reply
  6. Tomi Engdahl says:

    How to introduce intelligent lighting into construction projects with IP/Power over Ethernet
    https://www.cablinginstall.com/articles/print/volume-26/issue-5/features/technology/how-to-introduce-intelligent-lighting-into-construction-projects-with-ip-power-over-ethernet.html?cmpid=enl_cim_cim_data_center_newsletter_2018-12-17&pwhid=6b9badc08db25d04d04ee00b499089ffc280910702f8ef99951bdbdad3175f54dcae8b7ad9fa2c1f5697ffa19d05535df56b8dc1e6f75b7b6f6f8c7461ce0b24&eid=289644432&bid=2327452

    IP/PoE lighting is key

    The key catalyst (disruptive technology) enabling this move to a lower-cost, more-functional IoT architecture is Internet Protocol/Power over Ethernet (IP/PoE) lighting. Today, several providers have open architecture solutions that allow you to install versatile fixtures from hundreds of manufacturers. Most IP/PoE lighting providers work with any LED fixture that operates within the current 60W PoE standards. This means that approximately 95 percent of all available LED lights can be used, including new higher-wattage and larger interior and exterior LED fixtures.

    As the industry moves forward with IP/PoE installations, it’s learning that cost of installing an IP/PoE fixture can be reduced by 10, 20, 30 dollars or even more, with each light being controlled, versus an uncontrolled high-voltage (HV) LED system install. This savings is only going to increase as the efficacy of power distribution and LED fixtures improves.

    If you are working with lighting consultants, explain that you are simply changing how lights are powered and controlled. Limit your suggestions on fixtures to efficacy and performance. The lighting consultants should continue to do their job, determining things like fixture type, aesthetic considerations, and light levels. They should develop the reflected ceiling plan, but instead of handing it to the electrical engineer to place high voltage behind it, you should work with them to build an IoT platform to support it. By adopting a solution that is not fixture-specific, you can enable lighting consultants to design as they always have, but to use IP/PoE lighting. Never battle over fixture selection. In that way, you remove the main obstacle to technology adoption that keeps a better solution out of the design. This type of opportunity exists within any base-building system.

    Right people, right skills, right motivation

    The ability to adopt a better technology with the right approach requires the right skillsets and motivation to discover the possibilities. Understanding that skillsets for technology adoption need to be inserted in design, bidding, building, commissioning, and planning for ongoing operations is key.

    Reply
  7. Tomi Engdahl says:

    Has PoE for lighting finally arrived?
    https://www.edn.com/electronics-blogs/led-diva/4461352/Has-PoE-for-lighting-finally-arrived-?utm_source=Aspencore&utm_medium=EDN&utm_campaign=social

    The IEEE 802.3bt standard, approved by the IEEE Standards Association Board on September 27, 2018, includes some significant enhancements for LED lighting systems. The main driver of this improvement is the specification for up to 90W of delivered power for cable lengths of up to 100m through the use of all four pairs of wires. This allows for daisy chaining of several luminaires, which can simplify the installation process.

    Reply
  8. Tomi Engdahl says:

    3 tips for successfully deploying 28 AWG patch cords for PoE
    https://www.cablinginstall.com/articles/2019/02/tips-on-deploying-28awg-patch-cords-for-poe-power-delivery.html?cmpid=&utm_source=enl&utm_medium=cim&utm_campaign=cim_data_center_newsletter&utm_content=2019-03-04&eid=289644432&bid=2382195

    In August 2018, the industry received some exciting news when TIA approved 28 AWG cable for use in data centers and enterprise network applications. Previously not compliant with TIA standards, 28 AWG patch cords can now be used.

    When compared to 24 AWG patch cords, 28 AWG patch cords reduce cable diameter size by more than 50%.

    This month, we received even bigger news about 28 AWG patch cords: They can now be used to support power delivery

    28 AWG patch cabling can support today’s higher PoE levels, up to 60W. (100W PoE is not supported without approval from the AHJ because of NEC 2017 limitations.) For applications requiring more than 30W of power, TSB-184-A-1 provides guidance on separation of bundles.

    Patch cords smaller in diameter than 28 AWG shall not be used to support the delivery of power. It’s also important to note that 28 AWG cable cannot be used as horizontal or backbone cable – only as used patch cabling to connect an endpoint device to something else.

    Reply
  9. Tomi Engdahl says:

    Proposed legislation in Texas would classify some PoE cabling as electrical work
    https://www.cablinginstall.com/articles/2019/04/texas-sb1004-hb1141-poe-electrical-work.html?cmpid=&utm_source=enl&utm_medium=email&utm_campaign=cim_data_center_newsletter&utm_content=2019-04-29&eid=289644432&bid=2430366

    Bills making their way through Texas’s Senate and House of Representatives will, if passed as currently written, categorize any cabling circuit capable of supplying more than 50 watts of power to be electrical work requiring a licensed electrician. As a practical matter, that would mean any cabling circuits that can support Type 3 or Type 4 power sourcing equipment (PSE) or powered devices (PDs), as defined in IEEE 802.3bt, would fit that definition. As specified in IEEE 802.3bt, a Type 3 PSE provides a maximum of 60 watts and a Type 3 PD receives a maximum of 51 watts, while a Type 4 PSE provides a maximum of 90 watts and a Type 4 PD receives a maximum of 71.3 watts.

    Existing legislation in Texas identifies types of electrical work that require a license, and also identifies exceptions to the licensing requirement. One of the exceptions in the current Texas law is: “the design, installation, erection, repair, or alteration of Class 1, Class 2, or Class 3 remote control, signaling, or power-limited circuits, fire alarm circuits, optical fiber cables, or communications circuits, including raceways, as defined by the National Electrical Code.”

    SB 1004 and HB 1141 add the following wording to the end of the above-quoted exception: “that operate at less than 50 volts and that are not capable of supplying or controlling more than 50 volt-amperes or 50 watts of power.”

    Reply
  10. Tomi Engdahl says:

    Eight-port switch supports new IEEE 802.3bt PoE standard to create cost-effective smart lighting systems
    https://www.electropages.com/2019/05/eight-port-switch-supports-new-ieee-8023bt-poe-standard-create-cost-effective-smart-lighting-systems?utm_campaign=2019-05-23-Electropages-Email-Newsletters&utm_source=newsletter&utm_medium=email&utm_term=article&utm_content=Eight-port+switch+supports+new+IEEE+802.3bt+PoE+standard+to+create+

    Microchip Technology, via its Microsemi subsidiary, now offers a cost-effective eight-port PoE switch which gives guaranteed power of 60W per port for all eight ports simultaneously. Excellent for digital ceiling installations, the IEEE 802.3bt-compliant PDS-408G PoE switch operates noise-free with a fanless design.

    Reply
  11. Tomi Engdahl says:

    Compact RJ45 F/F coupler eases 10G Cat 6A connectivity
    https://www.cablinginstall.com/connectivity/article/14033761/compact-rj45-ff-coupler-eases-10g-cat-6a-connectivity?cmpid=&utm_source=enl&utm_medium=email&utm_campaign=cim_data_center_newsletter&utm_content=2019-05-28&eid=289644432&bid=2453670

    R&M’s female-to-female RJ45 coupler supports PoE up to a performance level of 90 Watts (4PPoE) in compliance with IEEE 802.3bt.

    Reply
  12. Tomi Engdahl says:

    Home> Community > Blogs > Power Points
    Will PoE++ be helpful, a headache, or both?
    https://www.edn.com/electronics-blogs/power-points/4461947/Will-PoE-be-helpful-a-headache–or-both-

    The long-awaited availability of IEEE 802.3 “Physical Layer and Management Parameters for Power over Ethernet over 4 pairs” (also known as IEEE 802.3bt-2018 and PoE++) is official

    Note that PoE++ with its higher-power rating is not a simple drop-in upgrade to existing Ethernet cabling. First, you have to use the new Category 6A Ethernet cabling and there are classes 1 through 8 of available power it can deliver. The new cabling is identified by certification logos

    Despite their efforts, I worry that there will be counterfeit Cat-6A cables with those logos, promising performance they really can’t provide.

    Even with the genuine cable, there are serious thermal issues, and this may be especially troublesome as we don’t associate data cables with dissipation.

    As a result, the actual power rating will be far less than 100 W since significant temperature rise can occur,

    My concern is that PoE++ is transforming a simple loop consisting of source, on/off switch, copper cable, and load into yet another protocol-driven system where a complex sequence of queries, responses, and validations are needed to get it working the first time, and then keep it working.

    There’s a lot to be said in favor of the simple-to-connect, simple-to-troubleshoot direct-connect approach.

    So, where will PoE++ go? Will it become widespread and commonplace? Or will its use be limited to highly-specialized applications such as commercial building lighting and control? Will it become another “could have been a contender” that just didn’t catch on as anticipated? Check back in five years or so, it will be interesting to see.

    Reply
  13. Tomi Engdahl says:

    IEEE standard compliant PoE uses power supplies in swiches that supply around 48V power to line only when they detect valid standard compliant device connected.

    Then there are proprietary “passive PoE” systems that supply whatever voltage (12, 24, 48 V) all the time to line. If you plug non-poe device to such port depending your device design nothing happens or you can smell small terminating resistors burning… (but can even work after burning smell accident).

    Reply
  14. Tomi Engdahl says:

    How Power Over Ethernet (PoE) Works
    https://hackaday.com/2019/10/24/how-power-over-ethernet-poe-works/

    A remote Ethernet device needs two things: power and Ethernet. You might think that this also means two cables, a beefy one to carry the current needed to run the thing, and thin little twisted pairs for the data. But no!

    Power over Ethernet (PoE) allows you to transmit power and data over to network devices. It does this through a twisted pair Ethernet cabling, which allows a single cable to drive the two connections.

    PoE can also be an advantage in cases where power is not easily accessible or where additional wiring simply is not an option.

    Historically, PoE was implemented by simply hooking extra lines up to a DC power supply. Early power injectors did not provide any intelligent protocol, simply injecting power into a system. The most common method was to power a pair of wires not utilized by 100Base-TX Ethernet. This could easily destroy devices not designed to accept power, however. The IEEE 802.3 working group started their first official PoE project in 1999, titled the IEE 802.3af.

    This standard delivered up to 13 W

    In 2009, the IEEE 802.3 working group released the second PoE standard, IEEE 802.3at. This added a power class that could deliver up to 25.5 W, allowing for pan and tilt cameras to use the technology.

    IEEE 802.3bt standard that utilizes all four twisted pairs to deliver up to 71 W to a powered device

    But this power comes at a cost: Ethernet cables simply don’t have the conductive cross-section that power cables do, and resistive losses are higher.

    The proposed 70 W IEEE 802.3bt standard can put as much as 30 W of heat into the wires.

    Reply
  15. Tomi Engdahl says:

    Combining a DPS5005 DC-DC module with a TPS2378 PoE controller results in a compact, flexible, and extremely handy power supply.

    Power Over Ethernet to Your Workbench: Dr. Scott M. Baker’s DPS5005 PoE Benchtop PSU Build
    https://www.hackster.io/news/power-over-ethernet-to-your-workbench-dr-scott-m-baker-s-dps5005-poe-benchtop-psu-build-647732b55795

    Combining a DPS5005 DC-DC module with a TI TPS2378 PoE controller results in a compact, flexible, and extremely handy power supply.

    Reply
  16. Tomi Engdahl says:

    Panduit’s connectors certified to IEEE 802.3bt 90W PoE
    https://www.cablinginstall.com/connectivity/article/14072357/panduit-panduits-connectors-certified-to-ieee-8023bt-90w-poe

    Product manager Frank Straka says the company was two-and-a-half years ahead of the 802.3bt standard, as Panduit’s connectors were third-party verified to 90 watts that long before the standard was published.

    Reply
  17. Tomi Engdahl says:

    Webinar asks: Should licenses be necessary for PoE cabling installation?
    https://www.cablinginstall.com/connectivity/article/14073651/webinar-asks-should-licenses-be-necessary-for-poe-cabling-installation?utm_source=CIM+Weekly&utm_medium=email&utm_campaign=CPS191213017&o_eid=7211D2691390C9R&rdx.ident%5Bpull%5D=omeda%7C7211D2691390C9R&oly_enc_id=7211D2691390C9R

    Belden and the National Systems Contractors Association will present a seminar on December 17 exploring recent legislative activities that would have required licenses for PoE-cabling work.

    On Tuesday, December 17 at 2:00pm EST/11:00am PST, Belden and the National Systems Contractors Association (NSCA) will jointly present an online seminar addressing the prospect that an electrician’s license will be required to install cabling that will support remote power delivery via Power over Ethernet.

    “Recent proposed state legislation would require integrators and low-voltage installers to have an electrical license to plug in PoE ports or pull and install PoE cable,” Belden said in an announcement of the upcoming seminar. “Why is this happening?” the company asked.

    “Some people incorrectly believe that PoE is dangerous,” Belden continued. “Others believe that new technology should be handled by someone with a license. But most people already, and safely, come into contact with PoE cables every day. This webinar will look at the delivery of remote power using PoE from a safety standpoint and what can be done to mitigate legislation that could exclude certain installers from installing PoE cable.”

    Reply
  18. Tomi Engdahl says:

    PoE Texas unveils Power Over Ethernet ‘lid’ for Intel mini-PC
    https://www.cablinginstall.com/connectivity/article/14073768/poe-texas-unveils-power-over-ethernet-lid-for-intel-minipc?utm_source=CIM+Weekly&utm_medium=email&utm_campaign=CPS191219013&o_eid=7211D2691390C9R&rdx.ident%5Bpull%5D=omeda%7C7211D2691390C9R&oly_enc_id=7211D2691390C9R

    The GBT-NUC lid accepts uPoE or IEEE 802.3bt dual signature Power over Ethernet and delivers power and data for Intel NUC mini PCs wherever users need it.

    Reply
  19. Tomi Engdahl says:

    The Lightkraken supports ArtNet and E1.13 protocols, can drive most programmable LED strips, has a built-in web configurator, and more.

    Obtainium Consulting’s Lightkraken Is a PoE++ LED Strip Driver That Can Handle 70W of Power
    https://www.hackster.io/news/obtainium-consulting-s-lightkraken-is-a-poe-led-strip-driver-that-can-handle-70w-of-power-2d4e0603b8f0

    The Lightkraken supports ArtNet and E1.13 protocols, can drive most programmable LED strips, has a built-in web configurator, and more.

    San Francisco-based Obtainium Consulting is offering a first-of-its-kind LED strip driver that draws power via a PoE++ (802.3bt Type 4) connection, which allows it to consume up to 70W of power and data through a Cat5 network cable. According to Obtainiumm, the Lightkraken supports ArtNet and E1.13 protocols, as well as the most common programmable LED strips (WS2812b, APA102 etc.). It can also be hardwired to drive analog RGB(W) strips using PWM at 16-bit resolution, offers 5V/12V/24V outputs via the selector switch, and has a built-in web configurator.

    The Lightkraken is compatible with switches that support all PoE standards (Type 1/2/3/4 up to 70W max) and uses a 100/10Mbit Ethernet connection with a DHCP or static IP address.

    it can handle up to 1,020 LEDs per output for RGB strips

    Obtainium Consulting is currently selling the Lightkraken on Tindie for $69 and up

    https://www.tindie.com/products/tinicuro/lightkraken/#specs

    Reply
  20. Tomi Engdahl says:

    Why understanding PoE now is crucial for electricians
    https://www.cablinginstall.com/testing/article/14074743/why-an-understanding-of-poe-is-now-crucial-for-electricians?utm_source=CIM+Weekly&utm_medium=email&utm_campaign=CPS200117025&o_eid=7211D2691390C9R&rdx.ident%5Bpull%5D=omeda%7C7211D2691390C9R&oly_enc_id=7211D2691390C9R

    To ring in the new decade, IDEAL Networks is urging today’s electricians to master new skills and equipment to cope with the growing use of PoE in intelligent lighting applications.

    “In just a few short years the use of PoE has migrated from IT devices into building systems like lighting, HVAC and access control,” observes Tim Widdershoven, marketing director for IDEAL Networks, who adds, “However, the growth of PoE presents issues for electricians, who may have never had cause to work on anything other than traditional electrical cable infrastructure.”

    As is commonly known, in 2018 a new industry standard, IEEE 802.3bt, was ratified and provides the specifications for PoE equipment to provide up to 90 watts of power to devices over twisted-pair Ethernet cabling. This amount of power combined with high-efficiency LED light fixtures makes PoE lighting practical.

    “PoE offers clear benefits in many applications, not least that installing just one set of cabling infrastructure is less disruptive and generally more cost effective,” continues Ideal’s Widdershoven. “So to stay ahead of clients’ demands, it’s crucial for electricians to learn the necessary PoE testing and troubleshooting skills now.”

    “Electricians installing or servicing PoE lighting systems need to be familiar with the components of PoE lighting systems to ensure proper operation and easily troubleshoot any problems that arise,” asserts Widdershoven. “Even when live, a PoE system is not always energized — so this means that familiar, standard electrical testing tools cannot be used to test PoE systems.”

    Instead, a range of PoE testers is now available on the market, from simple LED voltage detectors (like a neon electrical outlet checker) to testers which measure voltage and power available to the Powered Devices (PD) on a circuit.

    “The rise of PoE presents electrical contractors with a fantastic opportunity to confidently expand their service offering,” concludes Ideal’s Widdershoven. “Electricians who are equipped with the right testing tools and a functional knowledge of PoE systems will be able to both ensure that new installations deliver the expected performance and quickly identify faults when troubleshooting.”

    Reply
  21. Tomi Engdahl says:

    PoE lighting market projected to 33.6% CAGR through 2027
    https://www.cablinginstall.com/design-install/article/14092816/poe-lighting-market-projected-to-336-cagr-through-2027?utm_source=CIM+Weekly&utm_medium=email&utm_campaign=CPS200131038&o_eid=7211D2691390C9R&rdx.ident%5Bpull%5D=omeda%7C7211D2691390C9R&oly_enc_id=7211D2691390C9R

    Rising organizational need for cost-effective lighting solutions, plus the increasing penetration and decreasing cost of LEDs, are seen by technology industry analyst Research and Markets as major factors driving the growth of the market.

    The “Power Over Ethernet Lighting – Global Market Outlook (2018-2027)” report has been added to the offering of ResearchAndMarkets.com (Dublin, Ireland). According to the researcher, the global Power over Ethernet lighting market accounted for $191.61 million in 2018 and is expected to reach $2,598.31 million by 2027 growing at a CAGR of 33.6% during the forecast period.

    “The utilization of PoE can improve the execution of a smart lighting system in an office or industrial application,” notes the report’s summary. The analyst adds, “Industries and factories are now concentrating on energy-efficient lighting solutions attributable to the government regulations for energy saving. Along these lines, PoE lighting is among the favored solutions being adopted by them.”

    Reply
  22. Tomi Engdahl says:

    With up to 4W of power coming down the same cable as network connectivity, the PoE FeatherWing aims to make Adafruit Industries Feather deployment even easier.

    Silicognition Prepares a Crowdfunder for the PoE
    FeatherWing, Ethernet and 4W of Power for Feathers

    https://www.hackster.io/news/silicognition-prepares-a-crowdfunder-for-the-poe-featherwing-ethernet-and-4w-of-power-for-feathers-41f34dc71247

    With up to 4W of power coming down the same cable as network connectivity, the PoE FeatherWing aims to make Feather deployment easier.

    “Adafruit provides an Ethernet FeatherWing for its popular Feather ecosystem — a valuable option for IoT and automation projects. But it has its limitations. The Feather still needs to be powered separately, and no globally unique MAC address is provided for the user, making deployment hard,” the company explains of then inspiration behind its latest design.

    “What if we could fix these issues? What if there was a drop-in replacement that would not only provide Ethernet, but also power your Feather, and give you a globally unique MAC? And still be 100% compatible in size, connections and software support? Enter the PoE-FeatherWing!”

    The PoE FeatherWing supports IEEE 802.3at Class 1, Mode A and Mode B Power over Ethernet (PoE) with up to 4W available to connected devices. The Ethernet connectivity itself is provided by a WIZnet W5500 Ethernet controller,

    https://www.crowdsupply.com/silicognition

    Reply
  23. Tomi Engdahl says:

    PoE Powers Christmas Lights, But Opens Up So Much More
    https://hackaday.com/2019/12/31/poe-powers-christmas-lights-but-opens-up-so-much-more/

    The decoration is powered exclusively from power-over-Ethernet, with a PIC microcontroller translating Art-Net DMX-over-Ethernet packets into commands for the LED string. The control board is designed from the ground up and includes all the PoE circuitry

    Reply
  24. Tomi Engdahl says:

    Glen Akins’ Latest PoE Build Saves Costs, BOM with a Silvertel Ag5300 Module
    https://www.hackster.io/news/glen-akins-latest-poe-build-saves-costs-bom-with-a-silvertel-ag5300-module-5f755be72fd2

    A clever bit of circuit design and some smart software turns an RGB LED floodlight into a PoE powerhouse — complete with tablet control.

    Glen Akins is back with yet another Power-over-Ethernet (PoE) project — but this time he’s using a Silvertel Ag5300 PoE+ with integrated DC/DC converter, which can offer “big cost savings and help to reduce the overall parts count.”

    Usually, Akins builds his projects around a TI TPS2378 PoE+ classification IC – “the lowest cost solution, [but] requires quite a few other components to operate” — or a Molex Ethernet jack with built-in magnetics and PoE+ support — “the highest cost solution but requires very few external components to operate.”

    This time Akins has opted for a Silvertel Ag5300 PoE+ module, which “sits somewhere in the middle,” requiring a jack, magnetics, two bridge rectifiers, and a transient suppressor, but including an isolated 12V or 24V DC/DC converter

    “I’m going to replace the PDS-150e with a small power/control board that can directly power and control a single 10 watt ColorBurst 4 fixture from any 802.3at/PoE+ capable switch and an industry-standard Art-Net controller sitting anywhere on the network. I’ll use Synthe-FX’s Luminair 3 software running on an iPad Mini to send Art-Net packets to the board and control the light.

    https://bikerglen.com/blog/poe-powered-led-floodlight/

    Reply
  25. Tomi Engdahl says:

    The “Interoperability Inside” Logo
    The Ethernet Alliance’s Gen2 Certification Program delivers Power over Ethernet standards and interoperability, and ultimately helps improve ROI.
    https://www.electronicdesign.com/power-management/article/21122636/the-interoperability-inside-logo?utm_source=EG+ED+Analog+%26+Power+Source&utm_medium=email&utm_campaign=CPS200204030&o_eid=7211D2691390C9R&rdx.ident%5Bpull%5D=omeda%7C7211D2691390C9R&oly_enc_id=7211D2691390C9R

    With exponential growth in the Internet of Things and the countless number of sensors, cameras, controllers, and other remote devices being widely deployed around the world, Power over Ethernet (PoE) has become a leading solution for more streamlined deployments and greater cost savings. What’s more, as power demands increase for such things as wireless access points needed to serve an increasingly mobile-connected public, the issues of standards conformance and assured interoperability of equipment have come to the forefront.

    a readily available testing suite that delivers on the interoperability promise of IEEE 802.3 PoE standards.

    Much like the renowned “Intel inside” branding associated with personal computers, the certification program is based on marking equipment with “EA Certified” PoE logos to identify port attributes. It brings a multitude of benefits across the entire ecosystem—all of which have a positive impact on ROI. The logo delivers an “Interoperability Inside” promise to the various stakeholders in a PoE-deployed system.

    The logo itself is visually straightforward, simply showing “arrow out, power out” and “arrow in, power in.” Clearly, the number on the load needs to be less than or equal to the number on the switch. This was a key issue in Gen1 of the certification program.

    Now, however, instead of switches primarily sending the same type of power across all ports (Type 2 for example), a more likely future scenario on a 24-port chassis might be having four ports rated to send Type 4 power, four to eight of Type 3, and the rest being Type 2. For installers, that’s going to be a lot more challenging as PoE installations become increasingly complicated. The “EA Certified” solution allows for installers to just quickly look at the switch port labeling instead of having to open an instruction manual and identify exactly which ports are set at a particular power level.

    Overall, equipment manufacturers with the “EA Certified” PoE logo can not only expect fewer calls, but they can also achieve lower support costs for customer calls by deferring those from non-certified suppliers, particularly in an environment where there’s diminishing support from system vendors.

    Improved End-Customer Perception

    Because the logo signifies a range of benefits, having it increases the value proposition of PoE for the end customer. This is very much in line with the aforementioned “Interoperability inside” model and can positively impact everyone in the channel.

    Many working in the PoE space share an opinion that one of the top things hindering PoE adoption at a higher percentage, other than its power limitations, is that there’s no one broadly defined and accepted vision of PoE. Too much confusion exists in the market. Despite having a standard for decades, no one recognized test suite translates the standard into certification tests and an easily identified mark.

    Reduced Evaluation Costs, Faster Time to Market

    Consider a smaller end-equipment manufacturer that might only ship 100,000 switches, and maybe only one model that integrates the PoE feature. Hypothetically, the company may only be shipping 5,000 PoE models. Even if you already have an existing validation suite to test for PoE functionality under the IEEE 802.3at standard, there’s still a whole lot of work to get ready for the latest standard and to validate your switch at a black-box level.

    By trusting in the Ethernet Alliance PoE certification and logo, you needn’t worry about the nuts and bolts of incorporating a PoE feature. Providing end-equipment manufacturers with this level of confidence ultimately saves on evaluation costs and allows them to significantly reduce equipment cycle timelines in order to bring products to market faster and cheaper.

    An affordable official third-party test suite alleviates companies from having to develop a program in-house thats confirm its equipment is IEEE 802.3bt-compatible.

    To learn more about the Ethernet Alliance PoE Certification Program, visit https://ethernetalliance.org/poecert/

    Reply
  26. Tomi Engdahl says:

    PixPoE: Putting Plenty of Pixels Wherever You Can Plumb Some Cat5!
    Glen Akins’ project is a solid reference for anyone looking to implement a PoE+-powered device.

    https://www.hackster.io/news/pixpoe-putting-plenty-of-pixels-wherever-you-can-plumb-some-cat5-9a8f24c3b485

    Reply
  27. Tomi Engdahl says:

    Ethernet extender kit deploys PoE up to 1000 meters
    https://www.cablinginstall.com/connectivity/article/14172892/ethernet-extender-kit-deploys-poe-up-to-1000-meters?utm_source=CIM+Weekly&utm_medium=email&utm_campaign=CPS200327045&o_eid=7211D2691390C9R&rdx.ident%5Bpull%5D=omeda%7C7211D2691390C9R&oly_enc_id=7211D2691390C9R

    Antaira Technologies’ LEP-301M-KIT Ethernet extender kit is designed to overcome the 100 meter limitation of copper Ethernet technology.

    Antaira Technologies has announced the expansion of its industrial networking infrastructure family with the introduction of its rugged LEP-301M-KIT Ethernet extender kit, designed to overcome the 100 meter limitation of copper Ethernet technology.

    The LEP-301M-KIT goes beyond simply extending Ethernet by also extending Power over Ethernet (PoE) to distances up to 1000 meters.

    Extending PoE long distances for safety’s sake
    https://www.cablinginstall.com/standards/network-protocols/article/16465985/extending-poe-long-distances-for-safetys-sake

    Hudson Valley Community College used a rugged system to power cameras in its new parking garage.

    Reply
  28. Tomi Engdahl says:

    Power over Ethernet Gets Stronger
    https://www.electronicdesign.com/power-management/article/21808849/power-over-ethernet-gets-stronger

    Sponsored by Digi-Key and ON Semiconductor: The latest PoE standard—802.3bt—pushes available power for PDs to the highest levels yet, unleashing a new torrent of components and devices to meet those guidelines.

    Reply
  29. Tomi Engdahl says:

    Siemon joins HDBaseT Alliance
    https://www.cablinginstall.com/ip-security-av/article/14175555/siemon-joins-hdbaset-alliance?utm_source=CIM+Weekly&utm_medium=email&utm_campaign=CPS200508040&o_eid=7211D2691390C9R&rdx.ident%5Bpull%5D=omeda%7C7211D2691390C9R&oly_enc_id=7211D2691390C9R

    The global network infrastructure specialist has joined the HDBaseT Alliance as an Adopter member.

    The HDBaseT Alliance advances and promotes the adoption of HDBaseT technology as the global standard for ultra-high-definition, digital connectivity. Since its founding in 2010 by LG Electronics, Samsung Electronics, Sony Pictures Entertainment, and Valens, the Alliance has brought together leading names in the consumer electronics, professional AV, industrial and automotive sectors, and has today more than 200 members and thousands of products.

    Reply
  30. Tomi Engdahl says:

    Ethernet Alliance ‘PoE Survey’ infographic reveals deployment insights
    https://www.cablinginstall.com/standards/article/14175938/ethernet-alliance-poe-survey-infographic-reveals-deployment-insights?utm_source=CIM+Weekly&utm_medium=email&utm_campaign=CPS200515030&o_eid=7211D2691390C9R&rdx.ident%5Bpull%5D=omeda%7C7211D2691390C9R&oly_enc_id=7211D2691390C9R

    Survey reveals four of five users experience challenges with PoE deployments; majority of responses affirm integration process noticeably improves with Ethernet Alliance-certified products and solutions.

    The Ethernet Alliance, the global consortium dedicated to the continued success and advancement of Ethernet technologies, has announced results of its recent Power over Ethernet (PoE) product certification survey.

    The data reveals some 78 percent of respondents experienced difficulties with PoE deployments — but that 72 percent expect noticeable improvement with products certified through the Ethernet Alliance’s PoE Certification Program.

    The Ethernet Alliance notes that, lacking a registered trademark, the use of the term “PoE” is not formally regulated, allowing any vendor to freely describe products and solutions as PoE-enabled. Additionally, the survey reveals that terminologies such as “PoE+”, as well as non-standard PoE implementations, are causing confusion with device interoperability among technicians, designers, and end users.

    Further findings from the survey are available in a newly released infographic, available at: https://bit.ly/EA-PoEInfographic2020.

    Reply
  31. Tomi Engdahl says:

    Power Up Your Feather Projects with the PoE FeatherWing!
    https://www.hackster.io/news/power-up-your-feather-projects-with-the-poe-featherwing-cfe6e23dc0e3

    Patrick Van Oosterwijck’s board takes that PoE we all know and love and fits it into the footprint of a Feather!

    Reply
  32. Tomi Engdahl says:

    Understanding Power-over-Ethernet Deployments
    A survey conducted by the Ethernet Alliance reveals how those working with and installing PoE devices feel about the murky interoperability climate and the impact of product certification.
    https://www.electronicdesign.com/power-management/whitepaper/21136438/understanding-poweroverethernet-deployments?utm_source=EG+ED+Analog+%26+Power+Source&utm_medium=email&utm_campaign=CPS200710081&o_eid=7211D2691390C9R&rdx.ident%5Bpull%5D=omeda%7C7211D2691390C9R&oly_enc_id=7211D2691390C9R

    Power over Ethernet (PoE) has become nearly ubiquitous for powering IoT devices, such as access points, phones, and cameras, and this may be a prelude to the next wave of growth. The Dell’Oro Group forecasts annual shipments of PoE ports to grow from 130 million in 2020 to 168 million in 2024.

    As PoE proliferates, so have the range of PoE capable devices using different brand names and terminology, with no visible way to distinguish between standardized and non-standardized solutions. As a result, interoperability issues and market confusion have increased.

    The newly adopted IEEE 802.3bt Power over Ethernet standard extends the offered power up to 90 W, opening the door to a new generation of devices that include large displays, advanced cameras, and computing devices. Respondents are expecting to deploy devices based on this standard in the coming year, with 27% planning to deploy devices supplying or using more than 60 W as defined in the standard

    78% of respondents reported one or more of the problems as outlined in the chart, with 29% reporting that one or more of these problems had been significant. And while many are planning to add high-power IEEE 802.3bt devices to their mix, 59% felt the problems with those devices would be about the same or worse.

    What’s the reason for these difficulties? The term “PoE” isn’t registered, and any vendor can claim PoE capabilities. Currently, there are three published IEEE 802.3 PoE standards, and they’re designed to be interoperable. These standards define eight different wattage levels or classes, which can be delivered via four configurations: Type 1 and 2 that use two pairs, and Types 3 and 4 that use four pairs. Further, vendors have created additional terms, such as PoE+ and PoE++ as well as Cisco’s Universal PoE (UPOE), which are “add-ons” to the standards.

    Finally, some PoE implementations exist outside of the standards. For example, “passive” PoE implementations provide “always on” power, which isn’t negotiated between the PSE and PD. Techs in the field, and even designers, can become quickly confused about what will work with what.

    the Ethernet Alliance PoE Certification Program. This program provides a methodology for certifying products so that they’re interoperable with other IEEE-802.3-based PoE solutions, and providing simple labeling of such products.

    The rigorous test regimen of the Ethernet Alliance PoE Certification validates that the PoE devices strictly adhere to IEEE 802.3 PoE standards. Customers who purchase Ethernet Alliance PoE Certified products can expect effortless integration and operation as a result.

    A strong claim, but what does the market think of the program? The Ethernet Alliance PoE certification program is in its infancy, with the first testing completed in Q1 of 2020. So it’s not surprising only 37% of the respondents were aware of the program. Once the program was explained in the survey, though, their expectations were strongly positive—72% expected certified products would be vastly or noticeably better in one of the four problem areas discussed earlier

    Customers also indicated they would prefer a certified product. Given two similarly featured and priced products, 22% said they would definitely choose the certified product and 95% said they would be influenced by the certification status

    How much would customers be willing to pay for certified products? Half of the respondents stated they would pay a premium of 30% or greater for a certified product. This represents a major competitive advantage, especially for suppliers who are early adopters of this process.

    The combination of simplicity and cost savings provided by PoE assures this technology will see continued growth. The opportunity for manufacturers, installers, and users will grow even faster if customers are confident that their solutions can be implemented quickly and reliably.

    Reply
  33. Tomi Engdahl says:

    90-W Power over Ethernet Explained
    https://www.electronicdesign.com/power-management/whitepaper/21137799/90w-power-over-ethernet-explained

    Learn how the new 90-W 802.3bt Power over Ethernet (PoE) standard can open the door to powering almost any Ethernet device with a single Ethernet cable.

    The PoE Connection

    “Being powerful is like being a lady. If you have to tell people you are, you aren’t.” —Margaret Thatcher

    On the surface, PoE sounds complex: Inject high power onto a cable designed for data without disrupting the high-speed traffic the cable is carrying. Fortunately, the Ethernet standard and the cable design greatly simplify this technology. As shown in Figure 1, inside the Ethernet cable itself are four twisted pairs of wires. Ethernet is an isolated network, so each twisted pair connects to a transformer. All PoE does is inject a dc voltage (~54 V) onto the twisted pairs of the Ethernet cable through center taps on the transformers.

    In a two-pair power configuration (802.3af, 802.3at), one twisted pair is positive and the other is negative. In a four-pair power configuration (802.3bt), two twisted pairs are positive and two are negative. The power-sourcing equipment (PSE) is the device putting power onto the cable, and the powered device (PD) is the device taking power off of the cable.

    Finally, the PoE standards enable the PSE to power the twisted pairs in either polarity. Therefore, the PD must have input bridges (diodes or FETs) to set the polarity of the incoming power.

    Detection

    “Eighty percent of success is showing up.” —Woody Allen

    Now we know how to put power onto the Ethernet cable, so the PSE can just blast power down the cable whenever something is connected, right? Wrong! Applying power to a non-PoE device can damage it. PoE starts with a detection phase in which the PSE determines if the connected device is a PD requesting power. The PSE applies two voltages between 2.7 and 10.1 V onto the Ethernet cable, and the PD presents a 25-kΩ resistance, signaling to the PSE that a valid PD is connected

    Classification

    “Never sacrifice your class to someone who has none.” —Unknown

    Once a valid PD is detected, the PSE and PD then do an analog handshake known as “classification,” in which the PD requests a power “class” and the PSE then tells the PD what class is granted. PoE technology uses the terms type and class when discussing power. Type simply denotes the kind of analog handshake from the PSE. Class defines the maximum power the PSE will put onto the cable and the maximum power the PD can draw from the cable. Because PoE follows the Ethernet standard, the cable can be up to 100 meters in length, so a fair amount of power is lost in the cable.

    The amount of current drawn by the PD during classification is, confusingly enough, referred to as the classification signature or classification current. 802.3bt defines five classification signatures the PD can draw during classification.

    Reply
  34. Tomi Engdahl says:

    FuN
    This new power over Ethernet wiring scheme promises to provide more power than the current 90-100W PoE standard, is simpler and cheaper. There are still some safety issues that maybe cannot be solved?

    https://m.facebook.com/groups/2204579521?view=permalink&id=10160643849499522

    Don’t underestimate power of a IT Dept. guy
    #OTW

    https://www.facebook.com/124628051515678/posts/640123283299483/

    Reply
  35. Tomi Engdahl says:

    Conductors easily pass through the RJ45 connector for fast and easy verification of wire sequence. Operating temperature -40ᴼ to 70ᴼC Current rating 1.5Amps Dielectric withstanding voltage 1000Volts AC RMS 60Hz, 1 minute Contact resistance ≤ 20mΩ @ 100mA max. 50mV max.

    https://static1.squarespace.com/static/56029752e4b0763e15c4e7ca/t/5e2040e64293956c31b5381f/1579172075188/ONE-RJ45+Connectors+Datasheet.pdf

    Voltage rating: 125 VAC RMS. Dielectric strength: 1000 VAC … RJ.
    http://52ebad10ee97eea25d5e-d7d40819259e7d3022d9ad53e3694148.r84.cf3.rackcdn.com/UK_ACA_RJA66-H1100-GFH-4_DS.pdf

    RJ45 Connectors – Farnell
    VOLTAGE RATING 50V DC / 35V AC.
    http://www.farnell.com/datasheets/1581551.pdf

    Ethernet media 300V
    https://www.ideadigitalcontent.com/files/11994/1585-td001_-en-p.pdf

    Reply
  36. Tomi Engdahl says:

    Yhä useammin laite saa virtansa Ethernetin kautta
    https://etn.fi/index.php/13-news/11248-yha-useammin-laite-saa-virtansa-ethernetin-kautta

    Modernit pk-yritykset kohtaavat yhä enemmän haasteita liiketoiminnassa tarvittavien PoE-laitteiden (Power over Ethernet) määrän kasvaessa. Yhä useammin erilaiset IoT-laitteet, reitittimet, valvontakamerat tai valaisimet on liitetty verkkoon vain Ethernetillä.

    Vastatakseen tähän kehitykseen verkkolaitteista tunnettu NETGEAR laajentaa PoE-mallistoaan uusilla hallinnoimattomilla PoE+ -kytkimillä, jotka antavat käyttöön suuremman tehon Ethernetin kautta. Lisksi tarjolle tuodaan PoE+/PoE++ -kytkimet, joiden Ultra60 PoE++ -portin kautta saadaan käyttöön jopa 60 wattia porttia kohti.

    https://www.netgear.com/landings/poe/

    Reply
  37. Tomi Engdahl says:

    Ethernet Alliance teams with UL to expand PoE Certification program’s reach
    https://www.cablinginstall.com/testing/article/14198126/ethernet-alliance-ethernet-alliance-teams-with-ul-to-expand-poe-certification-testing-programs-reach?oly_enc_id=7211D2691390C9R

    Approving UL as an additional third-party testing lab expands the worldwide coverage of the Ethernet Alliance PoE Certification program.

    Reply

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