Owners Manual

2. Follow the procedure listed in After working inside your system.
3. While booting, press F2 to enter System Setup and verify that the system detects the USB memory key.
Power supply units
NOTE: For more information, see the Technical specifications section.
CAUTION: If two PSUs are installed, both the PSUs must have the same type of label. For example, Extended Power
Performance (EPP) label. Mixing PSUs from previous generations of XC XR2 servers is not supported, even if the PSUs
have the same power rating. Mixing PSUs will result in mismatch condition or failure to turn the system on.
NOTE: When two identical PSUs are installed, power supply redundancy (1+1 – with redundancy or 2+0 – without
redundancy) is configured in system BIOS. In redundant mode, power is supplied to the system equally from both PSUs
when Hot Spare is disabled. When Hot Spare is enabled, one of the PSUs is put into the sleep mode when system
utilization is low in order to maximize efficiency.
NOTE: If two PSUs are used, they must be of the same maximum output power.
Removing a power supply unit
Prerequisites
CAUTION:
The system needs one power supply unit (PSU) for normal operation. On power-redundant system, remove
and replace only one PSU at a time in a system that is powered on.
1. Follow the safety guidelines listed in Safety instructions.
2. Follow the procedure listed in Before working inside your system.
3. Disconnect the power cable from the power source, and then remove the cable from the strap on the PSU handle.
4. Unlatch and lift the optional cable management arm if it interferes with the PSU removal.
For information about the cable management arm, see the system’s rack documentation at For additional information about
environmental certifications, please refer to the Product Environmental Datasheet located with the Manuals & Documents on
www.dell.com/poweredgemanuals.
Steps
Press the release latch and slide the PSU out of the system by using the PSU handle.
Figure 82. Removing a power supply unit
Installing and removing system components
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