EPS 2011-04

5-35

Installing and Connecting the HP Redundant / External Power Supplies

Recommended Connection Topologies

These LEDs do not indicate whether power is flowing or not. They only

indicate that the connections are good and that power is available. In a normal

operating ring, all of these LEDs should be on. These LEDs are also duplicated

on the HP 610 EPS rear panel.

Fault Conditions

A faulty backup power cable connection is indicated by an LED that goes off

for two connected HP 610 EPS units. One unit will have its “In” LED off, and

the other unit will have its “Out” LED off. These LEDs are replicated on both

the front and back of the HP 610 EPS.

A power supply failure is indicated by:

■ Blinking Internal Power Supply LED on the front and back of the

HP 610 EPS

■ EPS Backup Power “Out” LED off on the failed unit

■ EPS Backup Power “In” LED off on the next unit in line

■ Blinking Fault LED on switch connected to the failed HP 610 EPS

Replacement Procedures

In the event of a failure, this is the recommended procedure to follow to

replace a failed unit.

1. Identify the failed unit and schedule downtime for the attached PoE

devices.

2. Reduce the PoE load of the failed unit.

3. Remove the EPS cables.

4. Remove the backup power cables. Additionally, remove the cable

attached to the “Out” port of the previous unit.

5. Remove the AC power.

6. Remove the failed unit.

7. Install a new unit, then reverse this procedure.

Remember, it is the preferred procedure for connecting backup power cables

to attach the “IN” cable end before attaching the “OUT” cable end.