Power Supply Controls - IBM TotalStorage DS4300 Installation, User's, And Maintenance Manual

The power supply CRUs provide power to the internal components by converting
incoming ac voltage to dc voltage. One power supply CRU can maintain electrical
power to the unit if the other power supply is turned off or malfunctions. The power
supply CRUs are interchangeable (by reversing the locking levers).
Each power supply CRU has a built-in sensor that detects the following conditions:
v Over-voltage
v Over-current
v Overheated power supply
If any of these conditions occurs, one or both power supplies will shut down. All
power remains off until you cycle the power switches (turn the power switches off,
wait at least 30 seconds, then turn the power switches on). For more information,
see "Restoring power after an unexpected shutdown" on page 94 and "Restoring
power after an over-temperature shutdown" on page 96.
The power supplies are customer replaceable units (CRUs) and do not require
preventive maintenance.
v Always keep the power supplies in their proper places to maintain proper
controller-unit cooling.
v Use only the supported power supplies for your specific storage subsystem.
Lever
Power LED
AC power
connector
Fault LED
Strain-
AC power
relief clamp
switch
Figure 93. Power supply controls
The following power-supply controls on the rear of the storage subsystem are
shown in Figure 93:
Levers
Use these locking handles to remove or install a power supply.
Power LED
These green LEDs light when the storage subsystem is turned on and
receiving ac power.
Fault LEDs
These amber LEDs light if a power supply failure occurs or if the power
supply is turned off.
Hot-swap power
supplies
AC power
Strain-
connector
relief clamp
Chapter 5. Installing and replacing components
Lever
Power LED
Fault LED
AC power
switch
131