Port Management
PoE
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Cisco 350, 350X and 550X Series Managed Switches, Firmware Release 2.4, ver 0.4
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The following can be configured:
•
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 configured for the Port Limit mode are
retained.
NOTE
Changing the mode from Class Limit to Port limit and vice versa when the
device is operational forces the PD to reboot.
•
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 device
than the configured allocation allows (no matter if the device is in Class Limit or Port Limit
mode), the device 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 an SNMP trap
PoE Properties
NOTE
This section is only relevant for devices supporting PoE.
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.
Output power is disabled during power-on reboot, initialization, and system configuration to
ensure that PDs are not damaged.
