• If the load on the active PSU is more than 50%, then the redundant PSU is switched to the active state.• If the load on the active PSU falls below 20%, 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 on iDRACsettings, see the Integrated Dell Remote Access Controller User’s Guide at dell.com/support/home.Removing the power supply unit blankIf you are installing a second power supply unit, remove the power supply unit blank in the bay bypulling the blank outward.CAUTION: To ensure proper system cooling, the power supply blank must be installed in thesecond power supply bay in a non-redundant configuration. Remove the power supply blankonly if you are installing a second power supply.Figure 43. Removing and installing the power supply blank1. power supply blank 2. power supply bayInstalling the power supply unit blankInstall the power supply unit blank only in the second power supply unit bay.To install the power supply unit blank, align the blank with the power supply unit bay and push it intothe chassis until it clicks into place.Removing an AC power supply unitPrerequisitesCAUTION: Many repairs may only be done by a certified service technician. You should onlyperform troubleshooting and simple repairs as authorized in your product documentation, or asdirected by the online or telephone service and support team. Damage due to servicing that isnot authorized by Dell is not covered by your warranty. Read and follow the safety instructionsthat came with the product.101
