Eps Backup Power - HP ProCurve J8161A Installation And Getting Started Manual

Installing and Connecting the HP 600/610 External Power Supplies

EPS Backup Power

The purpose of the backup power is to provide redundancy to the PoE power
provided by the HP 610 EPS. Redundancy in PoE power can prevent loss of
power to PoE devices in the event of AC power failure or a power supply
failure on a connected HP 610 EPS.
Each HP 610 EPS incorporates a PoE power supply that is connected so it can
provide power to itself or another HP 610 EPS connected by a cable. The back
of the HP 610 EPS has backup power input and output connectors for
connecting multiple units together to back up each other. There are two
supported configurations for connectivity:
Daisy chain, sometimes referred to as a string. Used when incorporating
an unloaded unit as the backup unit for any failed unit in the string.
Therefore, this backup unit must be the first unit in the string.
Closed loop, sometimes referred to as a ring. This allows for distributing
loads across all units. See Limitations. HP recommends the closed-loop
configuration.
For example, in the closed loop, the first HP 610 EPS uses the output
connector to connect to the second or next HP 610 EPS input connector, and
so forth until the final HP 610 EPS output connector connects to the input
connector of the first HP 610 EPS. This then completes the connectivity and
closes the loop.
The main difference between the closed loop and the daisy chain is in the daisy
chain the output of the final HP 610 EPS does not connect to anything.
Recommended Connection Topologies
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