Power over Ethernet (PoE) products use network cables to deliver direct current (DC) power and data to network devices. PoE products use registered jack (RJ) connectors instead of AC-DC adapters and eliminate the need for separate power cables. PoE systems have three main parts: the power source, the devices to power, and network cables. Ethernet, a popular local area network (LAN) standard, uses a bus or star typology and lengths of Category 3 (Cat 3), Category 5 (Cat 5), Category 6 (Cat 6), coaxial, fiber optic, RG6/11, triaxial, Type 1 or twisted-pair cable. There are many Ethernet versions. Examples include 10Base-T or twisted pair Ethernet, 10Base-2 or thinnet, 10/100 Ethernet, 100Base-T or Fast Ethernet, and Gigabit Ethernet. In general power over Ethernet (PoE) products use Cat 3 or Cat 5 cables terminated with RJ-45 connectors, eight-wire devices that resemble modular telephone connectors.
Power over Ethernet (PoE) products comply with IEEE 802.3af, a power distribution standard from the Institute of Electrical and Electronics Engineers (IEEE). IEEE 802.3af provides for 48 VDC over 2 of the 4 available pairs on Cat 3 and Cat 5 network cables with a maximum current of 400 mA for a maximum load power of 15.4 W. The IEEE 802.3af standard also defines two types of PoE products: power sourcing equipment (PSE) and powered devices (PD). There are two basic types of PSEs: endspans and midspans. POE endspans (endspan hubs, PoE switches) are Ethernet switches with built-in transmission circuitry. PoE midspans (midspan hubs, PoE injectors) are power over Ethernet (PoE) products that stand between a regular Ethernet switch and the powered device (PD). There are many different types of PDs, including wireless fidelity (WiFi) amplifiers and antennas, voice over Internet protocol (VoIP) telephones, and web surveillance cameras.
Power over Ethernet (PoE) products use network cables to deliver direct current (DC) power and data to network devices. PoE products use registered jack (RJ) connectors instead of AC-DC adapters and eliminate the need for separate power cables. PoE systems have three main parts: the power source, the devices to power, and network cables. Ethernet, a popular local area network (LAN) standard, uses a bus or star typology and lengths of Category 3 (Cat 3), Category 5 (Cat 5), Category 6 (Cat 6), coaxial, fiber optic, RG6/11, triaxial, Type 1 or twisted-pair cable. There are many Ethernet versions. Examples include 10Base-T or twisted pair Ethernet, 10Base-2 or thinnet, 10/100 Ethernet, 100Base-T or Fast Ethernet, and Gigabit Ethernet. In general power over Ethernet (PoE) products use Cat 3 or Cat 5 cables terminated with RJ-45 connectors, eight-wire devices that resemble modular telephone connectors.
Power over Ethernet (PoE) products comply with IEEE 802.3af, a power distribution standard from the Institute of Electrical and Electronics Engineers (IEEE). IEEE 802.3af provides for 48 VDC over 2 of the 4 available pairs on Cat 3 and Cat 5 network cables with a maximum current of 400 mA for a maximum load power of 15.4 W. The IEEE 802.3af standard also defines two types of PoE products: power sourcing equipment (PSE) and powered devices (PD). There are two basic types of PSEs: endspans and midspans. POE endspans (endspan hubs, PoE switches) are Ethernet switches with built-in transmission circuitry. PoE midspans (midspan hubs, PoE injectors) are power over Ethernet (PoE) products that stand between a regular Ethernet switch and the powered device (PD). There are many different types of PDs, including wireless fidelity (WiFi) amplifiers and antennas, voice over Internet protocol (VoIP) telephones, and web surveillance cameras.
Suppliers of power over Ethernet (PoE) products provide PoE injectors, PoE splitters, and PoE controllers. Power over Ethernet (PoE) injectors or midspan hubs are POE products that supply the DC power. They carry numerous mechanical, electrical, environmental, and interface specifications. Power over Ethernet (PoE) splitters are PoE products that receive a unified PoE signal (data and power), and then separate the data and power onto two different lines for non-PoE devices. These power over Ethernet (PoE) products can also transform a nominal DC input from a PoE injector or other PSE to the required voltage for a non-PoE device. Power over Ethernet (PoE) controllers are PoE devices that detect the presence of LAN devices and transmit data and power accordingly. They have two main parts: a PoE switch and a PoE adapter.
