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NI PXIe-4480//4481 Calibration Procedure
It is possible to adjust the PXIe-4480 in either of two methods. The Minimum Time method
adjusts the voltage gain of all channels in parallel, utilizing the cable connections shown in
Figure 2. Alternatively, the Minimum Cabling method adjusts the voltage gain of each channel
sequentially, utilizing the cable connections shown in Figure 3. Performance is not affected by
the choice. The trade-off is simply between adjustment time and cabling complexity.
Note
In normal measurement applications, the input configuration of the
PXIe-4480 is controlled using the
range
parameter. However, during adjustment, the
input configuration is controlled using the
gain
parameter. This is a result of
employing an existing adjustment VI that is common across all DSA devices.
Minimum Time Method
Complete the following performance adjustment procedures to adjust the PXIe-4480 using the
“minimum time” method. To view a programming block diagram that provides an overview of
this adjustment procedure, go to
and enter the Info Code
PXIe448x
.
Initialization
1.
Call
DAQmxInitExtCal
(DAQmx Initialize External Calibration VI) to initialize the
calibration, using the following parameters:
deviceName:
Dev_name
password:
NI
calHandle:
&myCalHandle
Timebase Adjustment
2.
Using the equipment described in Table 1, connect the output of the function generator to
device input channel 0, as shown in Figure 6. Connect a BNC shorting cap to the other
device input channels.
3.
Configure the function generator to output a sine wave of 6.3 V
rms
(8.9 V
pk
) signal, no
offset, at a frequency of 90.000 kHz.
4.
Call
D
AQmxAdjustDSATimebaseCal
(DAQmx Adjust DSA Timebase Calibration VI)
with the following parameters:
calHandle
:
myCalHandle
referenceFrequency
:
90000.0
Voltage Offset Adjustment
5.
Using the equipment described in Table 1, connect a BNC shorting cap to each device input
channel, as shown in Figure 1.
6.
Call
DAQmxAdjustDSAAICalWithGainAndCoupling
(DAQmx Adjust DSA AI
Calibration With Gain and Coupling VI from the DAQmx Adjust DSA AI Calibration
Polymorphic VI), using the following parameters:
calHandle
:
myCalHandle
coupling
:
DAQmx_Val_DC
gain:
0
referenceVoltage:
0.0