Basic Administration Protocols
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Instruction Manual - NXA-ENET8-POE+
Setting the Port PoE Power Budget
Use the Administration > PoE > PSE page to set the maximum power provided to a port.
Command Usage
This switch supports both the IEEE 802.3af PoE and IEEE 802.3at-2009 PoE Plus standards. To ensure that the correct
power is supplied to powered devices (PD) compliant with these standards, the first detection pulse from the switch is
based on 802.3af to which the 802.3af PDs will respond normally. It then sends a second PoE Plus pulse that causes an
802.3at PD to respond as a Class 4 device and draw Class 4 current. Afterwards, the switch exchanges information with the
PD such as duty-cycle, peak and average power needs.
All the RJ-45 ports support both the IEEE 802.3af and IEEE 802.3at standards. For the NXA-ENET8-POE+, the total PoE
power delivered by all ports cannot exceed the maximum power budget of 160W.
The number of ports which can supply maximum power simultaneously to connected devices is listed in the following bullet
points:
30W (802.3at): 4
15.4W (802.3af): 8
7.5W (802.3af): 8
If a device is connected to a switch port and the switch detects that it requires more than the power budget set for the port
or to the overall switch, no power is supplied to the device (i.e., port power remains off).
If the power demand from devices connected to all switch ports exceeds the power budget set for the switch, the port
power priority settings are used to control the supplied power. For example:
If a device is connected to a low-priority port and causes the switch to exceed its budget, power to this port is not
turned on.
If a device is connected to a critical or high-priority port and would cause the switch to exceed its power budget as
determined during bootup, power is provided to the port only if the switch can drop power to one or more lower-priority
ports and thereby remain within its overall budget.
If a device is connected to a port after the switch has finished booting up and would cause the switch to exceed its
budget, power will not be provided to that port regardless of its priority setting.
If priority is not set for any ports, and there is not sufficient power to supply all of the ports, port priority defaults to
Port 1, Port 2, Port 3...Port 24, with available power being supplied in that sequence.
If priority is not set for any ports, and PoE consumption exceeds the maximum power provided by the switch, power is
shut down in the reverse sequence, starting from Port 24.
The following table lists the options on this page:
Administration - PoE (PSE) Options
Port
The port number on the switch. (Range: 1-8/22/24/48)
Admin Status
Enables PoE power on a port. Power is automatically supplied when a device is detected on a port,
providing that the power demanded does not exceed the switch or port power budget. (Default:
Enabled)
Mode
Shows whether or not PoE power is being supplied to a port.
Time Range Time
Name of a time range. If a time range is set, then PoE will be provided to an interface during the
specified period.
Time Range Status
Indicates if a time range has been applied to an interface, and whether it is currently active or
inactive.
Priority
Sets the power priority for a port. (Options: Low, High or Critical; Default: Low)
Power Allocation
Sets the power budget for a port. (Range: 3000-30000 milliwatts; Default: 30000 milliwatts)
Power Consumption
Current power consumption on a port