PoE/PoE+ Planning and Implementation Guide 2011-09

3-1
3
Planning and Implementation for the 2520 and
2520G Switches
This chapter discusses the planning process a user should follow to
successfully implement PoE using a 2520 or 2520G Switch. After
understanding what PoE is and its operating rules, the next step to
implementation is planning. See “General Considerations” page A-1, for an
example list of considerations during the planning phase.
Planning the PoE Configuration
This section assists you in building a PoE configuration. Using the following
examples you can plan, build, and connect PoE devices quickly and easily.
There are four configurations:
■ HP ProCurve 2520-8-PoE Switch with Gigabit Uplink
■ HP ProCurve 2520-24-PoE Switch with Gigabit Uplink
■ HP ProCurve 2520G-8-PoE Switch
■ HP ProCurve 2520G-24-PoE Switch
Each example shows a complete configuration. A table shows the PoE power
available to connected PoE devices.
Once you have selected your specific configuration and the PoE power
provided, you then add up the maximum amount of power each of your IEEE
802.3af-compliant devices require (use maximum power in watts, usually
found on a product’s data sheet). Adjust this total maximum power figure by
adding 16% to account for possible line loss. This value must be less than the
maximum power available shown in the table for your configuration.
The following examples only show the EPS connections, however, remember
these switches use a single internal power supply which provides two isolated
output voltages for switch and PoE functionality. One supply voltage provides
power for the switch functionality while the isolated voltage provides power
for the PoE functionality. If either voltage fails, the entire power supply shuts
down disconnecting all switch and PoE connections.