National Instruments Welding System 321645c-01 Manual De Usuario

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 National Instruments Corporation
G-11
NI-DAQ FRM for PC Compatibles)
Glossary
S
s
seconds
S
samples
sample counter
the clock that counts the output of the channel clock, in other words, the 
number of samples taken. On boards with simultaneous sampling, this 
counter counts the output of the scan clock and hence the number of scans.
scan
one or more analog or digital input samples. Typically, the number of input 
samples in a scan is equal to the number of channels in the input group. For 
example, one pulse from the scan clock produces one scan which acquires 
one new sample from every analog input channel in the group.
scan clock
the clock controlling the time interval between scans. On boards with 
interval scanning support (for example, the AT-MIO-16F-5), this clock 
gates the channel clock on and off. On boards with simultaneous sampling 
(for example, the EISA-A2000), this clock clocks the track-and-hold 
circuitry.
scan rate
the number of scans per second. For example, a scan rate of 10 Hz means 
sampling each channel 10 times per second.
SCXI
Signal Conditioning eXtensions for Instrumentation
SDK
Software Development Kit
SE
single-ended—a term used to describe an analog input that is measured 
with respect to a common ground
self-calibrating
a property of a DAQ board that has an extremely stable onboard reference 
and calibrates its own A/D and D/A circuits without manual adjustments by 
the user
shared memory
See dual-access memory
signal conditioning
the manipulation of signals to prepare them for digitizing
software trigger
a programmed event that triggers an event such as data acquisition
software triggering
a method of triggering in which you simulate an analog trigger using 
software. Also called conditional retrieval.