Dell PowerEdge R520 Technical Manual page 28

Figure 7 shows a 750W power supply unit extended from the R520 chassis.
Dell PSUs have achieved Platinum efficiency levels as shown in Table 16.
Form factor Output
495W AC
750W AC
Redundant 86mm
1100W AC
1100W DC
Cabled 550W AC
Optimized thermal management makes the PowerEdge R520 cool and quiet. Benefiting from smart
cooling fan speed control, the R520 can keep both high performance and good acoustics across a
wide range of ambient temperatures from 10°C to 35°C (50°F to 95°F) and to extended ambient
temperature ranges (see Table 25). Operating environments for the R520 can vary from the data
center to general-use spaces. In a typical configuration, the R520 is suitable for an open office
environment.
The thermal design of the PowerEdge R520 reflects the following:

Multiple sensors are monitored for thermal feedback control: The PowerEdge R520
dynamically controls system cooling fan speed based on responses from all component
temperature sensors, including processors, hard disk drives, DIMMs, storage cards, and the inlet
ambient temperature. Thermal control detects and responds to hardware configuration. Thermal
management adjusts cooling according to what the system really needs, and draws lower fan
power draw and generates lower acoustical noise levels than servers without such controls.
Class
10%
Platinum 82.0%
Platinum 82.0%
Platinum 89.0%
N/A 80.0%
Silver N/A
Efficiency targets by load
20% 50%
90.0% 94.0%
90.0% 94.0%
93.0% 94.5%
88.0% 91.0%
85.0% 88.0%
100%
91.0%
91.0%
92.0%
88.0%
85.0%