Power over Ethernet (PoE) injectors supply or inject direct current (DC) power through network cables to power network devices. They are sometimes called midspans or midspan hubs. Power over Ethernet (PoE) injectors comply with IEEE 802.3af, a power distribution standard from the Institute of Electrical and Electronics Engineers (IEEE). PoE injectors allow Ethernet, a common LAN protocol, to carry DC power along with data packets. PoE powered devices (PD) do not require separate power cables for local alternating current (AC). Instead, they use a standard RJ-45 jack and can be positioned away from wall outlets. PD power consumption is limited to 12.95 W. Power source equipment (PSE) outputs are limited to 15.4 W per RJ-45 port. Because longer Ethernet links exhibit a significant drop, voltages as high as 57 VDC may be used with PoE injectors.

Power over Ethernet (PoE) injectors carry mechanical, electrical, environmental, and interface specifications. Enclosure material, weight, length, height and width are basic parameters to consider. Electrical specifications for PoE injectors include inlet type, input voltage, data line pin-out, category 3 (CAT-5) cable pin-out, supply voltage, maximum current, nominal available output power, and nominal output voltage. Input currents may be specified at 110 VDC and 220 VDC, or over 100 – 250 VAC. Operating temperature and humidity are important environmental parameters to consider when selecting power over Ethernet (PoE) injectors for demanding applications. Interface specifications describe information about the input and output sockets. For example, the input for an Ethernet 10/100 Base-T connection may use an RJ-45 female socket. The data and power output may also use a RJ-45 socket, but with DC voltage on wire pairs 7-8 and 4-5. Some power over Ethernet (PoE) injectors are bundled with an integral power supply. Others are sold with accessories such as conversion cables for proprietary access points.

Power over Ethernet (PoE) injectors supply or inject direct current (DC) power through network cables to power network devices. They are sometimes called midspans or midspan hubs. Power over Ethernet (PoE) injectors comply with IEEE 802.3af, a power distribution standard from the Institute of Electrical and Electronics Engineers (IEEE). PoE injectors allow Ethernet, a common LAN protocol, to carry DC power along with data packets. PoE powered devices (PD) do not require separate power cables for local alternating current (AC). Instead, they use a standard RJ-45 jack and can be positioned away from wall outlets. PD power consumption is limited to 12.95 W. Power source equipment (PSE) outputs are limited to 15.4 W per RJ-45 port. Because longer Ethernet links exhibit a significant drop, voltages as high as 57 VDC may be used with PoE injectors.

Power over Ethernet (PoE) injectors carry mechanical, electrical, environmental, and interface specifications. Enclosure material, weight, length, height and width are basic parameters to consider. Electrical specifications for PoE injectors include inlet type, input voltage, data line pin-out, category 3 (CAT-5) cable pin-out, supply voltage, maximum current, nominal available output power, and nominal output voltage. Input currents may be specified at 110 VDC and 220 VDC, or over 100 – 250 VAC. Operating temperature and humidity are important environmental parameters to consider when selecting power over Ethernet (PoE) injectors for demanding applications. Interface specifications describe information about the input and output sockets. For example, the input for an Ethernet 10/100 Base-T connection may use an RJ-45 female socket. The data and power output may also use a RJ-45 socket, but with DC voltage on wire pairs 7-8 and 4-5. Some power over Ethernet (PoE) injectors are bundled with an integral power supply. Others are sold with accessories such as conversion cables for proprietary access points.

Power over Ethernet (PoE) injectors may comply with regulations and safety standards from organizations such as the U.S. Federal Communications Commission (FCC) and Underwriters Laboratories (PoE). FCC compliance may be specified as FCC Part 15, Sub Part B, Class B. Power over Ethernet (PoE) injectors that are sold in Europe should comply with the Restriction of Hazardous Substances (RoHS) and Waste Electric and Electronic Equipment (WEEE) directives from the European Union (EU).