Glossary
G-8
©
National Instruments Corporation
N
NC
normally closed, or not connected
NIST
National Institute of Standards and Technology
noise
an undesirable electrical signal—Noise comes from external sources such
as the AC power line, motors, generators, transformers, fluorescent lights,
soldering irons, CRT displays, computers, electrical storms, welders, radio
transmitters, and internal sources such as semiconductors, resistors, and
capacitors. Noise corrupts signals you are trying to send or receive.
nonreferenced signal
sources
signal sources with voltage signals that are not connected to an absolute
reference or system ground. Also called floating signal sources. Some
common example of nonreferenced signal sources are batteries,
transformers, or thermocouples.
NRSE
nonreferenced single-ended mode—all measurements are made with
respect to a common (NRSE) measurement system reference, but the
voltage at this reference can vary with respect to the measurement system
ground
O
onboard channels
channels provided by the plug-in data acquisition board
output settling time
the amount of time required for the analog output voltage to reach its final
value within specified limits
output slew rate
the maximum rate of change of analog output voltage from one level to
another
P
passband
the range of frequencies which a device can properly propagate or measure
PCI
Peripheral Component Interconnect—a high-performance expansion bus
architecture originally developed by Intel to replace ISA and EISA. It is
achieving widespread acceptance as a standard for PCs and work-stations;
it offers a theoretical maximum transfer rate of 132 Mbytes/s.
UM.book Page 8 Tuesday, July 14, 1998 10:37 AM
