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Chapter 2
Using the NI PXIe-4357
Measuring Temperature with LabVIEW or
LabWindows/CVI
The following procedure assumes you have already installed NI-DAQmx and connected
the RTD sensors to your device. Refer to the
NI PXIe-4357 and TB-4357 Installation Guide and Terminal Block Specifications
document for
pinouts and additional signal connection content.
To measure temperature using LabVIEW or LabWindows/CVI, do the following:
1.
Call the AI Temp RTD instance of the DAQmx Create Virtual Channel VI in LabVIEW
(
DAQmxCreateTask
and
DAQmxCreateAIRTDChan
functions in LabWindows/CVI).
2.
Specify the physical channel for the device connected to the RTD signal. The physical
channel is the terminal at which you measure an analog signal.
3.
Specify a name, such as
myRTDChannel
, to assign.
4.
Select the appropriate values for the RTD type, resistance configuration, excitation
(internal), excitation value (0.9 mA), and range inputs.
Note
You have now created a task. A task is a software entity that encapsulates the
physical channels—the terminals at which you measure an analog signal—along
with other channel-specific information such as the range, terminal configuration,
and custom scaling. A task also includes timing and triggering.
5.
Call the DAQmx Start Task VI (
DAQmxStartTask
in LabWindows/CVI).
6.
Call the Analog 1D DBL 1Chan NSamp instance of DAQmx Read VI, select the number
of samples to acquire (
DAQmxReadAnalogF64
in LabWindows/CVI).
7.
Call the DAQmx Stop Task VI (
DAQmxStopTask
function in LabWindows/CVI) after the
desired number of samples have been acquired.
8.
Call the DAQmx Clear Task VI (
DAQmxClearTask
function in LabWindows/CVI).
