PoE – Power Over Ethernet

PoE, PoE+, and Passive PoE are different implementations of Power over Ethernet (PoE) technology, which allows electrical power to be transmitted along with data over Ethernet cables. This eliminates the need for separate power cables and simplifies the installation of network devices.

1. PoE (Power over Ethernet): PoE is a standard that enables power to be transmitted over Ethernet cables. With PoE, both power and data are carried over the same network cable, typically using Cat5e or Cat6 cables. This technology allows devices such as IP cameras, VoIP phones, and wireless access points to be powered directly from the network switch or PoE injector. The original PoE standard provides up to 15.4 watts of power (known as PoE Type 1 or 802.3af), which is sufficient for many low-power devices.
2. PoE+ (Power over Ethernet Plus): PoE+ is an enhanced version of PoE that provides higher power delivery. It is also known as PoE Type 2 or 802.3at. PoE+ can deliver up to 30 watts of power per port, which is useful for powering devices that require more power, such as pan-tilt-zoom (PTZ) cameras, video conferencing systems, and access points with multiple radios. PoE+ is backward compatible with PoE, so PoE+ devices can be powered by PoE switches, but PoE devices cannot be powered by PoE+ switches.
3. Passive PoE: Passive PoE is a non-standardized method of delivering power over Ethernet. Unlike PoE and PoE+, which use a negotiation process between the power sourcing equipment (PSE) and the powered device (PD), passive PoE simply applies a voltage to the Ethernet cable. Passive PoE does not adhere to any specific power standards, and the power levels and pin assignments can vary between devices and manufacturers. It is typically used with older or non-standard equipment that doesn’t support the standardized PoE standards.

It’s important to note that when using PoE or PoE+, you need compatible network devices (both the switch and the powered device) that support the respective PoE standard to ensure proper power delivery and device operation.