National Instruments SCXI-1521, Руководство пользователя

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Chapter 5 Using the SCXI-1521/B
© National Instruments Corporation 5-5 SCXI-1521/B User Manual
Note This is not a complete list of NI-DAQmx properties and does not include every
property you may need to configure your application. It is a representative sample of
important properties to configure for strain measurements. For a complete list of
NI-DAQmx properties and more information about NI-DAQmx properties, refer to your
ADE help file.
Perform Offset Null Compensation
The SCXI-1521/B provides offset null compensation circuitry to adjust
signal voltages to proper levels when the strain gauge is at rest (unstrained).
You can use a strain task or global channel to perform offset null
compensation. The offset null compensation is performed during the
configuration of the global channel(s). Refer to the
Creating a Strain
Global Channel or Task section of Chapter 3, Configuring and Testing ,
for information about offset null compensation when in MAX.
For more information about offset null compensation, refer to the Offset
Null Compensation section of Chapter 4, Theory of Operation .
Analog Input»Strain»Strain Gage»
Gage Factor AI.StrainGage.GageFactor Specifies the sensitivity
of the strain gauge
Analog Input»Strain»Strain Gage»
Poisson Ration AI.StrainGage.PoissonRatio Specifies the ratio of
lateral strain to axial
strain in the specimen
material
Analog Input»General Properties»
Signal Conditioning»Bridge»
Initial Bridge Voltage AI.Bridge.InitialVoltage Specifies in volts the
output voltage of the
bridge in the unloaded
condition
Analog Input»General Properties»
Signal Conditioning»Bridge»
Balance»Fine Potentiometer
Property AI.Bridge.Balance.FinePot Specifies by how much to
compensate for offset in
the signal. This value can
be between 0 and 4,095.
Analog Input»General Properties»
Signal Conditioning»Excitation»
Source AI.Excit.Src Specifies the source of
excitation
Table 5-1. NI-DAQmx Properties (Continued)
Property Short Name Description