Poe plus enabling ip convergance over twisted pair cabling
1 / 28

PoE Plus Enabling IP convergance over twisted pair cabling - PowerPoint PPT Presentation

  • Uploaded on

PoE Plus Enabling IP convergance over twisted pair cabling. PoE Plus. Definition Standards Advantages/Drawbacks Modelling Cabling Options Benefits of higher graded Cabling. PoE : what is it?.

I am the owner, or an agent authorized to act on behalf of the owner, of the copyrighted work described.
Download Presentation

PowerPoint Slideshow about 'PoE Plus Enabling IP convergance over twisted pair cabling' - sanam

An Image/Link below is provided (as is) to download presentation

Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author.While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server.

- - - - - - - - - - - - - - - - - - - - - - - - - - E N D - - - - - - - - - - - - - - - - - - - - - - - - - -
Presentation Transcript
Poe plus enabling ip convergance over twisted pair cabling

PoE PlusEnabling IP convergance over twisted pair cabling

Poe plus
PoE Plus

  • Definition

  • Standards

  • Advantages/Drawbacks

  • Modelling

  • Cabling Options

  • Benefits of higher graded Cabling

Poe what is it
PoE : what is it?

  • Power over Ethernet describes any system to transmit electrical power along with data over standard twisted-pair cable in an Ethernet network.

  • The IEEE802.3af standard provides the capability to deliver both power (max 12.95W) and data over standard ethernet Cat.3/Cat.5 cabling.

Actual applications
Actual applications

  • Power supply <13W

    • IP phone

    • Webcam

    • Wifi Accesspoint

Future applications
Future applications?

  • Charge of a laptop

  • Providing both power supply and internet connection in trains and planes

  • Peripheral devices : screen, printer, home theatre…

  • Power backup for PC

  • Power supply for specific PC


  • Advantages :

    • Only one cable to carry datas and power

    • Up to 100m

    • Ethernet connector standard (RJ45) is widespread

    • Compatible with Gigabit Ethernet (1000BASE-T)

    • centralized backup power

Challenges and answers
Challenges and Answers

  • Learnfrom the challenges at the beginning and how they have been answered

    • Data cables are not made for this use (copperconductors are toothin,

      • 24 AWG = diameter of 0.5106 mm)

    • Higher power levels over thincoppercableslead to temperaturerise in cables

      • What are the limits ?

      • Do weneed new cables?

Nexans thermal modell
Nexans Thermal Modell

  • 3D Modelling Project in Nexans Research Center, France

Nexans modelling results 1
Nexans Modelling Results (1)

  • Heating of Ethernet cable depending on the category

Nexans modelling results 2
Nexans Modelling Results (2)

  • Heating of a bundle of cat5e ethernet cables

Nexans modelling results 3
Nexans Modelling Results (3)

  • Power of 1A results in ~10° temperature rise in a bundle of 19 cables

Results for cat5e utp cable worst case
Results for Cat5e UTP cable (Worst Case)

  • Cat5e UTP usable if bundle size <100

Isc sc25 poe ad hoc result
ISC SC25 / POE Ad Hoc Result

  • ISO SC25 Temp. Rise Data provided to IEEE

    • For 100 cable bundles Cat5 UTP minimum: all pairs energised

Ieee choice
IEEE Choice

  • Maximum acceptable Temperature Rise = 10°

    • Max maximum rating for cable = 60°

    • Max temp for equipment / ambient temperature = 45 ° = 15° Max.

    • Including some tolerance finally 10° Temperature Rise accepted

  • Leads to limitation to 25 Watts

    • 10° TR equals 600 mA

    • using 57 Volts  24/25 Watts Limitation (using 2-pairs only)

  • 50 Watts target only achievable with 4 pairs but this is patented technology

    • No licenses available (PowerDesign)

  • Ieee standards
    IEEE Standards

    • The existing standard : IEEE802.3af (PoE)

      • 48V DC over two pairs of cat3/cat5 ethernet cable

      • 400mA per pair

      • 12.95W (with losses)

    • The future standard : IEEE 802.3at (PoE Plus)

      • Uses the up to four pairs of cat5e cable

      • 57V DC

      • 600mA per pair

      • Up to 25.5W


    • FINALLY:

      • POE PLUS is possible with ALL Copper LAN Cables !!

        • IEEE Standard based on worst case CAT5e UTP

        • No need for ‚thick‘ cables

    • Big Achievement:

      • Run POE PLUS and IP Convergance over existing LAN cabling

    • ..but some cabling can support it better than others.....

      • Get around some limitations and compromises made to enable worst case

    Benefits of better cable
    Benefits of better cable

    • Let us look into benefits of better cabling. This would potentially allow

      • Limit the temperature rise (and save energy for cooling(?))

      • Tolerate higher power levels (some equipment oversubscribes)

      • To use larger bundles than 100 cables or even “bundles of bundles”

      • Tolerate environments at higher temperature without reaching the 60° limit when using PoE+

      • Keep maximum distances (100m)

    Poe p 2 pairs
    POE /P 2 pairs

    Temperature Rise per cable grade remember to double temperature rise due to 4 pairs (IEEE) instead of 2 pair (used in comparison these chart) Almost linear behaviour from 2-4 pair!!!

    Temp rise per cable grade
    Temp Rise per Cable Grade

    Difference between AWG 23 and AWG 22 cables is 1° !!

    Tolerate higher power levels
    Tolerate higher power levels

    Cat7A cable would allow to run ~ double power level

    Larger bundle size
    Larger Bundle Size

    AWG 23

    10 bundels = 331 cables

    AWG 22

    10 bundels = 331 cables

    Impact on distance
    Impact on distance

    • All International Standards specify insertion loss requirements at 20° C and have quantified a small increase of attenuation of less than 0.2%/degree C for shielded cable and up to 0.6%/degree C for unshielded cable.

    • UTP Insertion Loss

      • Reduces by -0.6%/degree C

      • Example: +10° for UTP

        • 90m - 6% = 84,6 m link length

      • Example: 60° for UTP

        • 90m - 24% = 68,4 m link length

    • FTP Insertion Loss

      • Reduces by -0.2%/degree C

      • Example: +10° for FTP

        • 90m - 2% = 88,2m link length

      • Example: 60° for FTP

        • 90m - 8% = 82,8 m link length

    In High Temp envronments use higher cable grade to ensure 100m distance (application dependend f.ex. Cat5 app over Cat6 cabling)

    Impact for office cabling
    Impact for Office Cabling

    • High Impact estimated for Office Cabling where a frequent use of POE/P can be expected

      • Devices like VoIP Telephones, Sensors, Printers, thin clients, new generation laptops require pontially fully energised large bundles of cabling

  • Bundles Size in horizontal cabling = typically 100 FD, often larger than 100 cables

    • 1 Floor of 50 users equals 150 cables at 3 drops /users

  • Summary

    • POE/P is a key technology to enable IP Convergence

    • Cat5e UTP cabling is required as a minimum

      • 10° temperature rise at 600mA per pair

      • Max. bundle size = 100

    • Better cabling Higher Grade (Cat 6 and Cat7) or shielded cable allows to

      • Lowering the expected temperture rise

      • Use larger bundles sizes

      • Tolerate higher power level

      • Save energy for cooling in comms rooms

      • Enable full distance of 100m