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.


  1. Tomi Engdahl says:

    How ANSI/TIA-1179-A supports PoE LED lighting in healthcare

    – 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

  2. Tomi Engdahl says:

    How ANSI/TIA-1179-A supports PoE LED lighting in healthcare

    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.

  3. Tomi Engdahl says:

    Eliminating the blame game: How to test and certify your network for IoT readiness

    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.

  4. Tomi Engdahl says:

    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.

  5. Tomi Engdahl says:

    Has PoE for lighting finally arrived?

    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.

  6. Tomi Engdahl says:

    How to introduce intelligent lighting into construction projects with IP/Power over Ethernet

    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.

  7. Tomi Engdahl says:

    Has PoE for lighting finally arrived?

    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.

  8. Tomi Engdahl says:

    3 tips for successfully deploying 28 AWG patch cords for PoE

    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.

  9. Tomi Engdahl says:

    Proposed legislation in Texas would classify some PoE cabling as electrical work

    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.”

  10. Tomi Engdahl says:

    Eight-port switch supports new IEEE 802.3bt PoE standard to create cost-effective smart lighting systems

    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.

  11. Tomi Engdahl says:

    Compact RJ45 F/F coupler eases 10G Cat 6A connectivity

    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.

  12. Tomi Engdahl says:

    Home> Community > Blogs > Power Points
    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.


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