2 Follow the procedure listed in After working inside your system.Power supply unitsThe 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:• Two 550 W AC PSUs• One 450 W cabled AC PSUNOTE: For more information, see the Technical specificationssection.CAUTION: If two PSUs are installed, both the PSUs must have the same type of label. For example, Extended PowerPerformance (EPP) label. Mixing PSUs from previous generations of PowerEdge servers is not supported, even if the PSUs havethe 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 two identical PSUs are installed, power supply redundancy (1+1 – with redundancy or 2+0 – without redundancy) isconfigured in system BIOS. In redundant mode, power is supplied to the system equally from both PSUs when Hot Spare isdisabled. When Hot Spare is enabled, one of the PSUs is put into the sleep mode when system utilization is low in order tomaximize efficiency.NOTE: If two PSUs are used, they must be of the same maximum output power.Removing a power supply unit blankPrerequisiteFollow the safety guidelines listed in Safety instructions.StepIf you are installing a second 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 second PSU bay in a non-redundantconfiguration. Remove the PSU blank only if you are installing a second PSU.Figure 83. Removing a power supply unit blankNext stepInstall the second PSU.Installing and removing system components 93
