What is the maximum power output for POE++ per port?

The maximum power output per port for PoE++ (also known as IEEE 802.3bt standard) depends on the type of PoE++ used:

--- Type 3 (60W): Delivers up to 60 watts per port.

--- Type 4 (100W): Delivers up to 100 watts per port.

How PoE++ Achieves High Power Levels

PoE++ (IEEE 802.3bt) uses four-pair power transmission to achieve these higher power levels. This differs from earlier PoE standards (PoE and PoE+), which use only two pairs of wires within the Ethernet cable. Here’s how the different types of PoE compare in terms of power output:

Detailed Breakdown of PoE++ Power Output

1. Type 3 PoE++ (60W):

--- Switch Output: Supplies up to 60 watts per port.

--- Power at Device: Provides up to 51 watts at the device, factoring in cable loss (which can vary based on the length and quality of the Ethernet cable).

--- Applications: Type 3 PoE++ is suitable for moderately high-power devices like Wi-Fi 6 access points, PTZ IP cameras with advanced sensors, and multi-sensor devices.

2. Type 4 PoE++ (100W):

--- Switch Output: Delivers a maximum of 100 watts per port.

--- Power at Device: Depending on cable length, 71 to 90 watts are available at the device.

--- Applications: Type 4 is designed for very high-power devices, such as digital signage, LED lighting systems, and industrial IoT equipment that require robust power.

Cable Quality and Length Considerations

The power available at the device end (Powered Device, or PD) is always slightly less than what is supplied at the switch port (Power Sourcing Equipment, or PSE) due to power loss in the Ethernet cable. Factors that impact power loss include:

--- Cable Type: Higher-quality cables like Cat6 or Cat6a experience less power loss compared to Cat5e cables.

--- Cable Length: Longer cables experience more power loss, which can reduce the wattage available at the device end.

Using Cat6 or Cat6a cables helps minimize this loss and enables efficient delivery of power, especially for high-power PoE++ applications.

Safety and Power Management in PoE++

PoE++ incorporates several safety and power management features to ensure safe and efficient delivery of high power:

--- Device Detection and Classification: PoE++ switches use advanced classification to detect a connected device's power requirements and supply only the necessary power. Devices are classified into classes 5 to 8, with higher classes receiving more power.

--- Overload Protection: If a device tries to draw more power than the switch can provide, the port will shut down to prevent overheating or damage.

--- Temperature Control: High power output generates more heat, so PoE++ switches often include temperature sensors to monitor and manage heat levels.

Summary of PoE++ Power Output Benefits

The high power levels offered by PoE++ (up to 100 watts per port) enable it to support advanced devices without the need for additional power infrastructure, making it ideal for applications in smart buildings, industrial automation, IoT, and high-power network devices. The IEEE 802.3bt standard's intelligent power management and safety features further ensure that devices receive the right amount of power safely and efficiently.