SPOJE.NET

Tato stránka je pouze pro čtení. Můžete si pouze prohlédnout zdrojový kód, ale ne ho měnit. Zeptejte se správce, pokud si myslíte, že něco není v pořádku.

====== Gigabit PoE (802.3af) ======

  * http://en.wikipedia.org/wiki/Power_over_Ethernet#Power_capacity_limits
  * http://forum.mikrotik.com/download/file.php?id=10417&sid=6fc2e8eb2c2daca423ee4b91e19a1405
  * http://www.dipolnet.cz/poe_-_iee_802_3af_and_iee_802_3at_bib746.htm

  * **C = 100nF** (ceramic, stacked tin foil,...)
  * **L = 300uH**
    * Ferrite material 43 or 61 (toroid FT-37-61)
    * https://www.youtube.com/watch?v=t8mB6xz2NPI

{{http://www.valal.sk/upload/savefile_php/uploads/eb025411ea.png}}
{{http://www.infocellar.com/networks/new-tech/PoE/cable2.gif}}
{{http://electronicdesign.com/site-files/electronicdesign.com/files/uploads/2014/01/fig1.gif}}

===== Experiments =====

  * I've decoupled all of 8 gigabit ethernet conductors using 100nF ceramic capacitors and the link was still OK.
  * I've shorted + and - of 3 meters 100M ethernet pair through FT-50-61 toroid choke. For 4 and more windings it did not affected the link. When removing the winds the link quality was getting gradually worse.
  * I've put FT-50-61 toroid choke on + of the same pair and from 9-10 winds and up it prevented the ethernet from linking. When trying less winds the link quality was gradually better.
  * It's not good idea to use wire with 0.2mm diameter for more than 3A (too much voltage drop, too much heat). So probably 2A should be maximum.

SPOJE.NET

Uživatelské nástroje

Nástroje pro tento web

Nástroje pro stránku