Glossary
G-12
ni.com
power so
u
rce
An instr
u
ment that provides one or more so
u
rces of AC or DC power. Also
known as power s
u
pply.
ppm
Parts per million.
pretriggering
The techniq
u
e
u
sed on a DAQ device to keep a contin
u
o
u
s b
u
ffer filled with
data, so that when the trigger conditions are met, the sample incl
u
des the
data leading
u
p to the trigger condition.
p
u
lse
A signal whose amplit
u
de deviates from zero for a short period of time.
p
u
lse width
The time from the rising to the falling slope of a p
u
lse (at 50% amplit
u
de).
Q
q
u
adrat
u
re encoder
An encoding techniq
u
e for a rotating device where two tracks of
information are placed on the device, with the signals on the tracks offset
by 90° from each other. This makes it possible to detect the direction of the
motion.
R
range
The maxim
u
m and minim
u
m parameters between which a sensor,
instr
u
ment, or device operates with a specified set of characteristics. This
may be a voltage range or a freq
u
ency range.
real time
1. Displays as it comes in; no delays.
2. A property of an event or system in which data is processed and acted
u
pon as it is acq
u
ired instead of being acc
u
m
u
lated and processed at a
later time.
3. Pertaining to the performance of a comp
u
tation d
u
ring the act
u
al
time that the related physical process transpires so res
u
lts of the
comp
u
tation can be
u
sed in g
u
iding the physical process.
RSE
Referenced Single-Ended mode—All meas
u
rements are made with respect
to a common reference meas
u
rement system or a gro
u
nd. Also called a
gro
u
nded meas
u
rement system.
