poe power-reserved

The default ratio is 20%.

Usage Scenario

The PSE dynamically allocates power to each interface based on the power consumption of each interface. The power consumption of each PD keeps changing. The PSE periodically calculates whether the total power required by all connected PDs exceeds the upper limit of the available PoE power. If yes, the PSE automatically cuts off the power supply to the PD connected to the interface with the lowest priority to ensure the power supply to other PDs.

Sometimes, power consumption increases abruptly, and the remaining available power of the PSE cannot support the increase. The power supply to all PDs may be cut off due to overload protection before the PSE calculates the value that exceeds the total power and cuts off the power supply to interfaces with low priorities.

To prevent such a situation, you need to run the poe power-reserved command to properly set the reserved power of the PSE. The reserved power supports sharply increasing power requirements, so that the PSE has time to power off the PDs connected to interfaces with low priorities.

Precautions

• The reserved power should not exceed 20%. A larger value affects the power supply capability of the PSE.
• You can run the poe max-power command to set the maximum output power. The reserved power is calculated using the following formula: Reserved power = Maximum output power x Reserved power ratio.