Setting the Power Class for a PoE Power-Consuming Device
A power class specifies the maximum amount of power that a RUCKUS PoE+ or PoH device supplies to a power-consuming device. The following table shows the different power classes and their respective maximum power allocations.
Power Classes for PDs
Refer to Considerations for Setting Power Levels for essential information. Consider the following points when setting the power class for a PoE power-consuming device:
- The power class includes any power loss through the cables. For example, a PoE port with a power class of 3 (15.4 watts) receives a maximum of 12.95 watts of power after 2.45 watts of power loss through the cables. This is compliant with the IEEE 802.3af and 802.3at specifications for delivering inline power. Devices that are configured to receive less PoE power, for example, Class 1 devices (4 watts), experience a lower rate of power loss through the cables.
- The
RUCKUS PoE+ or PoH device adjusts the power on a port only if there are available power
resources. If power resources are not available, the following message is displayed
on the console and in the syslog:
PoE: Failed power allocation of 30000 mwatts on port 1/1/21. Will retry when more power budget.