:PROPERTIES:
:ID:       6de2329b-bdba-45ff-bfda-d4df5c2879c8
:ROAM_ALIASES: PoE
:END:
#+title: Power Over Ethernet

#+caption: Standard Types and Power Levels
| Name  | IEEE Standard         | Maximum PSE Power | PD Available Power |
|-------+-----------------------+-------------------+--------------------|
| PoE   | IEEE 802.3af (Type 1) | 15.4 W            | 12.95 W            |
| PoE+  | IEEE 802.3at (Type 2) | 30 W              | 25.50 W            |
| PoE++ | IEEE 802.3bt (Type 3) | 60 W              | 51 W               |
| PoE++ | IEEE 802.3bt (Type 4) | 90 W              | 71.3 W             |

#+caption: PoE Classes
| Class | Usage                                    | Classification current (mA) | Power range at PD (W) | Max power from PSE (W) |
|-------+------------------------------------------+-----------------------------+-----------------------+------------------------|
|     0 | Default                                  | 0–5                        | 0.44–12.94           |                   15.4 |
|     1 | Optional                                 | 8–13                       | 0.44–3.84            |                   4.00 |
|     2 | Optional                                 | 16–21                      | 3.84–6.49            |                   7.00 |
|     3 | Optional                                 | 25–31                      | 6.49–12.95           |                   15.4 |
|     4 | Valid for Type 2 (802.3at) devices[fn:1] | 35–45                      | 12.95–25.50          |                     30 |
|     5 | Valid for Type 3 (802.3bt) devices       | 36–44 & 1–4                | 40 (4-pair)           |                     45 |
|     6 | 36–44 & 9–12                            | 51 (4-pair)                 | 60                    |                        |
|     7 | Valid for Type 4 (802.3bt) devices       | 36–44 & 17–20              | 62 (4-pair)           |                     75 |
|     8 | 36–44 & 26–30                           | 71.3 (4-pair)               | 90                    |                        |


* Footnotes

[fn:1] Class 4 is not allowed for 802.3af devices