PoE/PoE+ Planning and Implementation Guide 2011-09

2-8

Operating Rules

Provisioning Power for PoE

All of these PoE switches support an external power supply that can provide

either redundant or extra PoE power. It is important to understand how PoE

power is provisioned in order to use these external power supplies efficiently.

The following chapters will discuss this in detail.

By connecting an external power supply you can optionally provision more

PoE wattage per port and or supply the switch with redundant 12V power to

operate should an internal power supply fail.

By installing a second power supply in the E5406zl/E8206zl or a third power

supply in a E5412zl/E8212zl chassis, depending on how many PoE ports are

being supplied with power, the switch can have redundant power if one power

supply fails. A Power Supply Shelf (external power supply) can also be

connected to the E5400zl/E8200zl switches to provide extra or redundant PoE

power.

For example, if the 5406zl has two 24-port PoE modules (J8702A) installed,

and all ports are using 15.4 watts, then the total wattage used is 739.2 watts

(48 x 15.4). To supply the necessary PoE wattage a J8713A power supply is

installed in one of the power supply slots.

To gain redundant power, a second J8713A must be installed in the second

power supply slot. If the first power supply fails, then the second power supply

can supply all necessary power.

HP ProCurve 2520-PoE Switches

Maximum PoE Power

The Switch 2520-8-PoE and the Switch 2520G-8-PoE provision 8 ports with its

PoE power supply of 67 watts for PoE applications compatible with the IEEE

802.3af standard and some pre-standard PoE devices. The Switch 2520-24-PoE

and the Switch 2520G-24-PoE provision ports 1-24 with 195 watts of power for

PoE applications compatible with the IEEE 802.3af standard.

Note There is no external power supply available for these switches.