PoE in different flavours

PoE, PoE+, PoE++, 4PPoE … read on to find out which PoE versions are recognized by the standard.

With Power over Ethernet (PoE) devices can be powered remotely via the data cable. IEEE 802.3 specifies three different PoE versions:

• PoE according to IEEE 802.3af provides up to 13 W of electrical power at the powered device
• PoE+ according to IEEE 802.3at provides up to 25.5 W of electrical power at the powered device
• 4PPoE according to IEEE 802.3bt provides up to 71.3 W of electrical power at the powered device
  (4PPoE is also called PoE++).

IEEE 802.3af and IEEE 802.3at have been integrated into the IEEE 802.3 main standard, but people still refer to them with the suffixes “af” and “at” to easily tell them apart.

Telegärtner has published a comprehensive white paper “Remote Powering“ on Power over Ethernet which can be downloaded from the Telegärtner website at www.telegaertner.com/whitepaper