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Glossary
shunt calibration
The method of calibrating the gain of a strain-gauge data acquisition
channel by placing a resistor of known value in parallel with a bridge
element.
signal conditioning
The manipulation of signals to prepare them for digitizing.
simulated strain
A strain measurement where the change in bridge output voltage is not
caused by deformation of the specimen being measured; rather, it is caused
by temporarily connecting a known resistance in parallel with one of the
bridge elements while all the strain gauges in the bridge remain unstrained.
simultaneous sample
and hold
A series of sample-and-hold circuits that are connected in a matter so as to
switch modes in unison.
Slot 0
Refers to the power supply and control circuitry in the SCXI chassis.
SLOT0SEL
Slot 0 select signal
SPICLK
serial peripheral interface clock signal
spot noise
The rms noise voltage or rms noise current in a frequency band 1 Hz wide
at the specified frequency.
STC strain gauge
self-temperature compensating strain gauge—Has a resistive temperature
coefficient that counteracts the thermal expansion coefficient of the
material to which the gauge is bonded; thus, makes the system insensitive
to changes in temperature.
strain
The fractional deformation of a body under an applied force; is usually
given in the units of microstrain, where one microstrain represents a
deformation of 10–6, or 0.0001%.
SX–
negative signal input terminal for channel X
SX+
positive signal input terminal for channel X
SYNC
Synchronization pulse for scanning (only used with modules featuring
simultaneous sample and hold).
system noise
A measure of the amount of noise seen by an analog circuit or an ADC
when the analog inputs are grounded.
© National Instruments Corporation
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SCXI-1520 User Manual