Managing Power-over-Ethernet Devices
Configuring PoE Properties
Cisco Small Business 200 1.1 Series Smart Switch Administration Guide
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PoE Configuration Considerations
PoE Configuration Considerations
There are two factors to consider in the PoE feature:
•
The amount of power that the PSE can supply
•
The amount of power that the PD is actually attempting to consume
You can decide the following:
•
Maximum power a PSE is allowed to supply to a PD
•
During device operation, to change the mode from Class Power Limit to
Port Limit and vice versa. The power values per port that were configured
for the Port Limit mode are retained.
•
Maximum port limit allowed as a per-port numerical limit in mW (Port Limit
mode).
•
To generate a trap when a PD tries to consume too much and at what
percent of the maximum power this trap is generated.
The PoE-specific hardware automatically detects the PD class and its power limit
according to the class of the device connected to each specific port (Class Limit
mode).
If at any time during the connectivity an attached PD requires more power from the
switch than the configured allocation allows (no matter if the switch is in Class
Limit or Port Limit mode), the switch does the following:
•
Maintains the up/down status of the PoE port link
•
Turns off power delivery to the PoE port
•
Logs the reason for turning off power
•
Generates a trap to a remote log server
Configuring PoE Properties
The
PoE Properties
page
enables selecting either the Port Limit or Class Limit PoE
mode and specifying the PoE traps to be generated.
These settings are entered in advance. When the PD actually connects and is
consuming power, it might consume much less than the maximum power allowed.
