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Power, thermal, and acoustics
Power supply units
Energy Smart power supplies have intelligent features, such as the ability to dynamically optimize efficiency while maintaining
availability and redundancy. Also featured are enhanced power- consumption reduction technologies, such as high- efficiency power
conversion and advanced thermal- management techniques, and embedded power- management features, including high- accuracy
power monitoring.
The following table shows the available power supplies for the PowerEdge R740xd2:
Wattage
Frequency
Voltage
Class
Heat dissipation
750W- WRAC
50/60Hz
115/230 VAC
Platinum
2891 BTU/hr
750W HVDC/WRAC
240VDC
Platinum
2902 BTU/hr
1100W WRAC
50/60Hz
115/230 VAC
Platinum
4100 BTU/hr
1100W HVDC/WRAC
380V
Platinum
4100 BTU/hr
The PowerEdge R740xd2 supports up to 2 AC or DC power supplies with 1+1 redundancy, auto sensing, and auto-switching
capability.
If two PSUs are present during POST, a comparison is made between the wattage capacities of the PSUs. In the event that the PSU
wattages don't match, the larger of the two PSU's is enabled. Also, there is a PSU mismatch warning displayed in BIOS, iDRAC, or on
the System LCD.
If a second PSU is added at run-time, in order for that particular PSU to be enabled, the wattage capacity of the first PSU must
equal the second PSU. Otherwise, the PSU will be flagged as unmatched in iDRAC and the second PSU will not be enabled.
Power supply efficiency
Dell EMC power supplies have achieved Platinum and Titanium efficiency levels as shown in the table below:
Table 6. PSU efficiency levels
Form factor
Output
Class
10%
20%
50%
100%
Redundant 86
mm
750W AC
Platinum
82.00%
90.00%
94.00%
91.00%
1100W AC
Platinum
89.00%
93.00%
94.50%
92.00%
1100W AC
380V
Platinum
90.00%
93.50%
95.00%
93.00%
750W
HVDC
Platinum
82.00%
90.00%
94.00%
91.00%
NOTE: 750W & 1100W HVDC power supplies are only available in China
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