If having both PSUs active is more efficient than having one PSU in the sleep state, the active PSU can
also activate the sleeping PSU.
The default PSU settings are as follows:
• If the load on the active PSU is more than 50 percent, then the redundant PSU is switched to the
active state.
• If the load on the active PSU falls below 20 percent, then the redundant PSU is switched to the sleep
state.
You can configure the hot spare feature by using the iDRAC settings. For more information about iDRAC
settings, see the
Integrated Dell Remote Access Controller User’s Guide
available at
Dell.com/
idracmanuals
.
Removing a redundant power supply unit
Prerequisites
CAUTION: Many repairs may only be done by a certified service technician. You should only
perform troubleshooting and simple repairs as authorized in your product documentation, or as
directed by the online or telephone service and support team. Damage due to servicing that is
not authorized by Dell is not covered by your warranty. Read and follow the safety instructions
that are shipped with your product.
CAUTION: The system requires one power supply unit (PSU) for normal operation. On power-
redundant systems, remove and replace only one PSU at a time in a system that is powered on.
1.
Follow the safety guidelines listed in the Safety instructions section.
2.
Disconnect the power cable from the power source.
3.
Disconnect the power cable from the PSU and remove the straps that bundle and secure the system
cables.
4.
Unlatch and lift the optional cable management arm if it interferes with PSU removal. For
information about the cable management arm, see the system’s rack documentation.
Steps
Press the release latch and pull the PSU out of the chassis.
104
