HP ProCurve 2520 Planning And Implementation Manual page 132

Planning and Implementation for the 5400zl/8200zl Switches
Configuration Examples
Figure 10-5. Example of a 5406zl with two power supplies, J8713A
This configuration (Figure 10-5) is an example of two power supplies
supplying 900 watts each for a maximum of 1800 watts to a fully loaded chassis
of 144 ports. Therefore out of the total 144 available ports, 116 can be powered
at 15.4 watts each.
Source of Power Watts Available
Two Internal PoE 1800 (without
Power Supplies redundancy)
(J8713A)
Two External Additional 1800
Power Supplies
(J8713A)
Alternatively, one power supply could be used to supply PoE power at 900
watts and the other power supply could be used as a secondary power supply.
If both power supplies are connected to different power sources, one could
backup the other in case of failure. With this option the user must manage the
PoE usage in order to maintain redundancy.
In this example the threshold command could be set at 50%, and if the switch
begins to use more than 900 watts an event message would be logged, allowing
you to adjust the PoE load or add a Power Supply Shelf for additional power
as required to obtain the best power balance for your operation.
Connecting a fully loaded external power supply can double the available PoE
power. See
10-12
Front
# of Ports Powered and Average
watts/Port
116 @ average 15.4 W each
144 @ average 7.5 W each
144 @ average 4.0 W each
144 @ average 15.4 W each
144 @ average 7.5 W each
144 @ average 4.0 W each
page 10-14.
900 watts 900 watts
for PoE for PoE
Power Supply
J8713A
Redundant # of Ports Powered and
Average watts/Port
58 @ average 15.4 W each
116 @ average 7.5 W each
144 @ average 4.0 W each
116 @ average 15.4 W each
144 @ average 7.5 W each
144 @ average 4.0 W each