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Power over Ethernet
Power over Ethernet
Device with Power Source | Powered End Station |
Appendix F: Power over Ethernet (PoE)
Power over Ethernet is a technique (defined by the IEEE802.3af standard) for providing power to Ethernet enabled devices over standard Category 5e cabling. Two techniques (Alternative A and Alternative B) are defined by the standard and supported by the PES1A/PESV1A.
Alternative A implements a simplex, or ‘phantom feeding’ method for delivering power to the end device. Power is carried on the same conductors
Data Pair
Power
Sourcing
Equipment
(PSE)
Data Pair
| 3 |
| 6 |
| 7 |
Negative | 8 |
Positive(+) | 4 |
| 5 |
| 1 |
| 2 |
3 |
|
| Data Pair |
6 |
|
7 |
|
8 | Negative |
| Powered |
| Device |
| (PD) |
4 | Positive(+) |
5 |
|
1 |
|
| Data Pair |
2 |
|
as data. Cabling for standard 10BaseT and 100BaseTX Ethernet (typically Category 5 cable with
Alternative B carries power over spare wire pairs in the cable. The power sourcing equipment applies positive voltage to pins 4 and 5. Negative voltage is applied to pins 7 and 8.
Operating voltage is typically 48 volts but may vary from 44 volts to 57 volts.
Device with Power Source | Powered End Station |
Figure 24. Power over Ethernet Alternative B
Data Pair
Power
Sourcing
Equipment
(PSE)
3 | 3 |
6 | 6 |
Negative | Negative |
Positive(+) | Positive(+) |
Data Pair
Powered
Device
(PD)
1 | 1 |
Data Pair | Data Pair |
2 | 2 |
Figure 23. Power over Ethernet Alternative A
Manual Documentation Number: | 49 |
50 | Manual Documentation Number: |
B&B Electronics Mfg Co Inc – 707 Dayton Rd - PO Box 1040 - Ottawa IL 61350 - Ph | B&B Electronics Mfg Co Inc – 707 Dayton Rd - PO Box 1040 - Ottawa IL 61350 - Ph |
B&B Electronics Ltd – Westlink Commercial Park – Oranmore, Galway, Ireland – Ph +353 | B&B Electronics Ltd – Westlink Commercial Park – Oranmore, Galway, Ireland – Ph +353 |