NonStop NS-Series Servers Site Preparation (H06.03+)

Glossary
HP Integrity NonStop NS-Series Site Preparation Guide—527836-005
Glossary-2
conduit
conduit. A tubular raceway, usually constructed of rigid or flexible metal, through which
insulated power and ground conductors or data cables are run. Nonmetallic conduits,
although available, are not recommended.
configuration. (1) The arrangement of enclosures, system components, and peripheral
devices into a working unit. (2) The definition or alteration of characteristics of an
object.
CPU. See central processing unit (CPU).
current. The flow of electrons in a conductor.
customer engineer (CE). See service provider.
dB. See decibel (dB).
dBm. Decibels as referenced to a milliwatt. A unit of measure that establishes 0 dBm equal
to 1 milliwatt. A negative value represents a decrease in power, and a positive value
represents an increase in power. See also decibel (dB).
DC. See direct current (DC).
decibel (dB). A unit of measure used to express a relative difference in power. A negative
value represents a decrease in power, and a positive value represents an increase in
power.
delta. A method for connecting a 3-phase power source (or load) in a closed series loop
with input (or output) connections made to each of the three junctions. The delta’s
physical arrangement resembles the delta character from the Greek alphabet.
direct current (DC). Electric current that flows in only one direction. Contrast with
alternating current (AC).
disk drive. A device that stores and accesses data on a magnetic disk. Random access to
addressable locations on a magnetic disk is provided by magnetic read/write heads.
drive. See disk drive.
dropout. A voltage loss of very short duration (that is, milliseconds).
duplex. Having two active processor elements, each contained in a separate slice, per
logical processor. Also called dual-modular redundancy (DMR).
earth ground. The connection of the electrical-grounding conductors to a dependable, low-
resistance contact with the soil.
EIA. Electronic Industries Association.
electric utility. The local utility service that, for a fee, supplies alternating-current (AC)
power to businesses and residences.