Intel EPS1U User Manual
Page 12

SSI
EPS1U Power Supply Design Guide, V1.1
STATUS
Recommended
An additional inrush current limit is recommended for some system applications that require multiple systems on a
single AC circuit. AC line inrush current shall not exceed 30 A peak for one-quarter of the AC cycle, after which,
the input current should be no more than the specified maximum input current from Table 3.
5.8 AC Line Transient Specification
STATUS
Recommended
AC line transient conditions shall be defined as “sag” and “surge” conditions. Sag conditions (also referred to as
“brownout” conditions) will be defined as the AC line voltage dropping below nominal voltage. Surge will be
defined as the AC line voltage rising above nominal voltage.
The power supply shall meet the requirements under the following AC line sag and surge conditions.
Table 4: AC Line Sag Transient Performance
Duration
Sag
Operating AC Voltage
Line Frequency Performance Criteria
Continuous
10%
Nominal AC Voltage ranges
50/60 Hz
No loss of function or performance
0 to 1 AC cycle
100%
Nominal AC Voltage ranges
50/60 Hz
No loss of function or performance
> 1 AC cycle
>10%
Nominal AC Voltage ranges
50/60 Hz
Loss of function acceptable, self-
recoverable
Table 5: AC Line Surge Transient Performance
Duration
Surge
Operating AC Voltage
Line Frequency
Performance Criteria
Continuous
10%
Nominal AC Voltages
50/60 Hz
No loss of function or performance
0 to ½ AC cycle
30%
Mid-point of nominal AC
Voltages
50/60 Hz
No loss of function or performance
5.9 AC Line Fast Transient Specification
STATUS
Recommended
The power supply shall meet the EN61000-4-5 directive and any additional requirements in IEC1000-4-5:1995
and the Level 3 requirements for surge-withstand capability, with the following conditions and exceptions:
•
These input transients must not cause any out-of-regulation conditions, such as overshoot and
undershoot, nor must it cause any nuisance trips of any of the power supply protection circuits.
•
The surge-withstand test must not produce damage to the power supply.
•
The supply must meet surge-withstand test conditions under maximum and minimum DC-output load
conditions.