SSI
EPS2U Power Supply Design Guide, V2.1
3Definitions/Terms/Acronyms
Required | The status given to items within this design guide, which are required to |
| meet SSI guidelines and a large majority of system applications. |
|
|
Recommended | The status given to items within this design guide which are not required to |
| meet SSI guidelines, however, are required by many system applications. |
|
|
Optional | The status given to items within this design guide, which are not required to |
| meet SSI guidelines, however, some system applications may optionally |
| use these features. |
|
|
Autoranging | A power supply that automatically senses and adjusts itself to the proper |
| input voltage range (110 VAC or 220 VAC). No manual switches or |
| manual adjustments are needed. |
|
|
CFM | Cubic Feet per Minute (airflow). |
|
|
Dropout | A condition that allows the line voltage input to the power supply to drop to |
| below the minimum operating voltage. |
Latch Off | A power supply, after detecting a fault condition, shuts itself off. Even if the |
| fault condition disappears, the supply does not restart unless manual or |
| electronic intervention occurs. Manual intervention commonly includes |
| briefly removing and then reconnecting the supply, or it could be done |
| through a switch. Electronic intervention could be done by electronic |
| signals in the Server System. |
|
|
Monotonically | A waveform changes from one level to another in a steady fashion, without |
| intermediate retracement or oscillation. |
Noise | The periodic or random signals over frequency band of 0 Hz to 20 MHz. |
|
|
Overcurrent | A condition in which a supply attempts to provide more output current than |
| the amount for which it is rated. This commonly occurs if there is a "short |
| circuit" condition in the load attached to the supply. |
|
|
PFC | Power Factor Corrected. |
|
|
Ripple | The periodic or random signals over a frequency band of 0 Hz to 20 MHz. |
|
|
Rise Time | Rise time is defined as the time it takes any output voltage to rise from |
| 10% to 95% of its nominal voltage. |
Sag | The condition where the AC line voltage drops below the nominal voltage |
| conditions. |
Surge | The condition where the AC line voltage rises above nominal voltage. |
|
|
VSB or Standby Voltage | An output voltage that is present whenever AC power is applied to the AC |
| inputs of the supply. |
MTBF | Mean time between failure. |
|
|
PWOK | A typical logic level output signal provided by the supply that signals the |
| Server System that all DC output voltages are within their specified range. |
|
|
- 6 -