National Instruments NI 4050 用户手册

ISA

industry standard architecture

isolation

a type of signal conditioning in which you isolate the transducer signals 
from the computer for safety purposes. This protects you and your 
computer from large voltage spikes and makes sure the measurements from 
the DAQ device are not affected by differences in ground potentials.

isolation voltage

the voltage that an isolated circuit can normally withstand, usually 
specified from input to input and/or from any input to the amplifier output, 
or to the computer bus

m

meters

MB

megabytes of memory

NI-DAQ

National Instruments driver software for DAQ hardware.

NMRR

normal mode rejection ratio—a measure of an instrument’s ability to reject 
a signal applied directly to the differential inputs of the instrument

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.

Ohm’s Law

(R=V/I)—the relationship of voltage to current in a resistance

overrange

a segment of the input range of an instrument outside of the normal 
measuring range. Measurements can still be made, usually with a 
degradation in specifications.