National Instruments BNC -2140 - Manual (Page 28)

Glossary
BNC-2140 User Manual G-4 ni.com
instrumentation
amplifier a circuit whose output voltage with respect to ground is proportional to the
difference between the voltages at its two inputs
I/O input/output—the transfer of data to/from a computer system involving
communications channels, operator interface devices, and/or data
acquisition and control interfaces
M
m meters
N
NC normally closed, or not connected
noise an undesirable electrical signal—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; 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; common
examples are batteries, transformers, or thermocouples
P
PCI Peripheral Component Interconnect—a high-performance expansion bus
architecture originally developed by Intel to replace ISA and EISA; offers
a theoretical maximum transfer rate of 132 Mbytes/s and is achieving
widespread acceptance as a standard for PCs and work-stations
pF picofarad—one-trillionth of a farad
ppm parts per million
R
rms root mean square—the square root of the average value of the square of the
instantaneous signal amplitude; a measure of signal amplitude