Enabling poe, Enabling poe for a poe interface – H3C Technologies H3C S5120 Series Switches User Manual
Page 716

1-3
Task
Remarks
them, so no
configuration is
required.
Optional
Configuring PoE Interface
through PoE Profile
Optional
Upgrading PSE Processing Software in Service
Optional
z
Before configure PoE, make sure that the PoE power supply and PSE are operating normally;
otherwise, you cannot configure PoE or the configured PoE function does not take effect.
z
Turning off the PoE power supply during the startup of the device might cause the PoE
configuration in the PoE profile invalid.
Enabling PoE
Enabling PoE for a PoE Interface
The system does not supply power to or reserve power for the PDs connected to a PoE interface if the
PoE interface is not enabled with the PoE function.
You are allowed to enable PoE for a PoE interface if the PoE interface will not result in PoE power
overload; otherwise, whether you can enable PoE for the PoE interface depends on whether the PoE
interface is enabled with the PoE power management function (for the detailed description of the PoE
interface power management function, refer to
Configuring PoE Interface Power Management
).
z
If the PoE interface is not enabled with the PoE power management function, you are not allowed
to enable PoE for the PoE interface.
z
If the PoE interface is enabled with the PoE power management function, you are allowed to
enable PoE for the PoE interface (whether the PDs can be powered depends on other factors, for
example, the power supply priority of the PoE interface).
The PSE supplies power for a PoE interface in the following two modes:
z
Over signal wires: The PSE uses the pairs (1, 2, 3, 6) for transmitting data in category 3/5 twisted
pair cables to supply DC power while transmitting data to PDs.
z
Over spare wires: The PSE uses the pairs (4, 5, 7, 8) not transmitting data in category 3/5 twisted
pair cables to supply DC power to PDs.