SSI America ERP2U manual Definitions/Terms/Acronyms, Required

SSI

ERP2U Power Supply Design Guide, V2.31

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.

- 8 -