Hot spare feature
Your system supports the hot spare feature that significantly reduces the power overhead associated with power supply unit (PSU)
redundancy.
When the hot spare feature is enabled, one of the redundant PSUs is switched to the sleep state. The active PSU supports 100
percent 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 the sleep state, the active PSU can also activate the sleeping
PSU.
The default PSU settings are as follows:
•
If the load on the active PSU is more than 50 percent, then the redundant PSU is switched to the active state.
•
If the load on the active PSU falls below 20 percent, 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 about iDRAC settings, see the
Integrated
Dell Remote Access Controller User’s Guide
available at
Dell.com/idracmanuals
.
Removing the power supply unit blank
Install the power supply unit (PSU) blank only in the second PSU bay.
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 are shipped with your product.
Follow the safety guidelines listed in the Safety instructions section.
Steps
If you are installing a second power supply unit (PSU), remove the PSU blank in the bay by pulling the blank outward.
CAUTION: Remove the PSU blank only if you are installing a second PSU.
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