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NI PXIe-4464 Calibration Procedure
Adjustment
If the NI PXIe-4464 successfully passed each of the verification procedures within the As Left
test limits
without adjustment
, then an adjustment is recommended, but not required, to warrant
the published specifications for the next calibration interval. If the device was not within the As
Left test limits, you can perform the adjustment procedure to improve the device accuracy and
reset the calibration interval.
In order to update the calibration date without performing adjustment, see the instructions in the
Updating the Calibration Date without Performing Adjustment
section.
The external calibration interval is listed in the
NI PXIe-4464 Specifications
. An adjustment is
required at least once within this interval. Performing the adjustment procedure automatically
updates the calibration constants, date, and temperature in the device EEPROM.
The following performance adjustment procedures describe the sequence of operation required
to adjust the NI PXIe-4464.
Initialization
1.
Call
DAQmxInitExtCal
(DAQmx Initialize External Calibration VI) to initialize the
calibration, using the following parameters:
deviceName:
Dev_name
password:
NI
calHandle:
&myCalHandle
Offset Adjustment
2.
Using the equipment described in Table 1, connect a BNC shorting cap to each device input
channel.
3.
Call
D
AQmxAdjustDSAAICalWithGainAndCoupling
(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
Note
Set the
gain
parameter to the value of the device gain setting being calibrated,
where 0, for example, represents 0 dB.
4.
Repeat step 3 for each of the remaining gain ranges, sequentially substituting the
gain
parameter with 10, 20, 30, -10, and -20.
Note
All ranges must be adjusted for offset for the calibration to be valid.
