1 acoustic requirements, 2 airflow requirements, 3 temperature requirements – SSI America ERP2U User Manual
Page 10: Acoustic requirements, Airflow requirements, Temperature requirements, Figure 2 system airflow impedance, Table 1 recommended acoustic sound power levels
SSI
ERP2U Power Supply Design Guide, V2.31
- 10 -
4.1 Acoustic
Requirements
STATUS
Recommended
It is recommended the power supplies have a variable speed fan based on temperature and loading conditions.
There are three different acoustic sound power levels defined at different ambient temperatures and loading
conditions.
Table 1 Recommended Acoustic Sound Power Levels
Idle
Typical
Max
Ambient
Temperature
28ºC 28ºC 45ºC
%
Loading
30% 60% 100%
Sound Power (BA)
5.2
5.6
6.1
4.2 Airflow
Requirements
STATUS
Recommended
The air shall exit the power supply on the AC inlet face. The power supply shall meet all requirements with the
below system airflow impedance presented to the power supplies airflow path.
Figure 2 System Airflow Impedance
System Flow Impedance - 2U
0.0
0.1
0.2
0.3
0.4
0.5
0.6
0
5
10
15
20
Power Supply Airflow (CFM)
S
yst
em
P
ressur
e
(
in
H
2
O)
4.3 Temperature
Requirements
STATUS
Recommended