Hot Spare feature
Your system supports the Hot Spare feature that significantly reduces the power overhead associated with power supply redundancy.
When the Hot Spare feature is enabled, one of the redundant PSUs is switched to the sleep state. The active PSU supports 100% of the load, thus operating at higher efficiency. The PSU in the sleep state monitors output voltage of the active PSU. If the output voltage of the active PSU drops, the PSU in the sleep state returns to an active output state.
If having both PSUs active is more efficient than having one PSU in a sleep state, the active PSU can also activate a sleeping PSU.
The default PSU settings are as follows:
•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 iDRAC settings, see the Integrated Dell Remote Access Controller User’s Guide at dell.com/support/home.
Removing an AC 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 came with the product.
CAUTION: The system requires one power supply for normal operation. On
NOTE: You may have to unlatch and lift the optional cable management arm if it interferes with power supply removal. For information about the cable management arm, see the system’s rack documentation.
Steps
1.Disconnect the power cable from the power source and from the power supply unit you intend to remove and remove the cables from the strap.
2.Press the release latch and slide the power supply unit out of the chassis.
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