Power Over Ethernet Interoperability Guide

Book excerpt: A Complete Guide to Transmitting Electrical Power and Data over Ethernet Cables Power over Ethernet Interoperability explains how to safely transmit DC power over an existing data network cabling structure so that separate AC electrical wiring is not needed to power up devices connected to the network. With a focus on cost-effective unshielded twisted pair (UTP) cables, this book provides proven methods for designing reliable Power over Ethernet (PoE) equipment and ensuring that it functions effectively. Details on the IEEE 802.3af/at standards and how various devices can operate from PoE are also contained in this practical resource. Coverage includes: The evolution of PoE Overview of PoE implementations Detection Classification Inrush and power-up Operation Maintain power and disconnect PoE state-machine diagrams Magnetics Isolation, PCB design, and safety Surge testing and protection Lab skills, thermal management, and decoupling N-pair power delivery systems Auxiliary power and flyback design