Power Supply Units; Hot Spare Feature; Removing A Power Supply Unit Blank - Dell EMC PowerEdge R940xa Installation And Service Manual

3. Insert the replacement USB memory key into the USB port.
Next steps
1. Install the air shrouds.
2. Follow the procedure listed in
3. While booting, press F2 to enter System Setup and verify that the system detects the USB memory key.

Power supply units

The power supply unit (PSU) is an internal hardware component which supplies power to the components in the system.
Your system supports one of the following:
• Four 2400 W, 2000 W, 1600 W, or 1100 W, 750 W AC PSUs
• Four 750 W DC PSUs (for China only)
• Four 1100 W DC PSUs
• Four 1100 W or 750 W (for China only) Mixed Mode HVDC PSUs
For more information, see Technical
CAUTION: If multiple 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 PowerEdge 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: Titanium PSU is nominally rated for 200 V AC to 240 V AC input only.
NOTE: When identical PSUs are installed, power supply redundancy (2+2 – with redundancy or 4+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 multiple PSUs are used, they must be of the same maximum output power.

Hot spare feature

NOTE: Before removing the power supply, ensure that your system is configured with a hot spare power supply.
NOTE: Ensure to check, if the system has multiple hot spare power supplies installed in it.

Removing a power supply unit blank

Prerequisites
Follow the safety guidelines listed in
Steps
If you are installing an additional PSU, remove the PSU blank in the bay by pulling the blank outward.
CAUTION: To ensure proper system cooling, the PSU blank must be installed in the empty PSU bays in a non-redundant
configuration. Remove the PSU blank only if you are installing a PSU.
after working inside your system.
specifications.
Safety Instructions.
Installing and removing system components 139