PoE classification lets a power sourcing equipment (PSE) assess a powered device’s (PD’s) requirements before allocating power. It follows detection, classification, startup, and normal operation, reducing the risk of damaging unsuitable devices or supplying excessive power. section 10.1.2
The operational sequence is:
- Detection applies low voltage to determine whether the connected device supports PoE. section 10.1.2
- Classification assesses the PD’s power needs and allocates power from the switch’s available budget. section 10.1.2
- Startup supplies the appropriate voltage; normal operation supplies power while monitoring current. section 10.1.2
Verify classification and allocation
Run show power inline. The output reports the available, used, and remaining power budget, plus each port’s device, class, and maximum allocation. A class 3 access point receives 15.4 watts in the example; class 1 and class 2 devices commonly receive 4 and 7 watts. section 10.1.2
