National Instruments PXIe-4480, Calibration Procedure, Page: 30 / 34

30 | ni.com | NI PXIe-4480//4481 Calibration Procedure
Note
Set the gain parameter to the value of the device gain setting being calibrated,
where 0, for example, represents 0 dB.
11. Configure the calibrator to output a 3.15 V
rms
signal at 1 kHz.
12. Repeat step 10 for the 6 dB gain range, substituting the gain parameter with 6 and the
referenceVoltage parameter with 3.15.
13. Configure the calibrator to output a 630 mV
rms
signal at 1 kHz.
14. Repeat step 10 for the 20 dB gain range, substituting the gain parameter with 20 and the
referenceVoltage parameter with 0.63.
15. Configure the calibrator to output a 315 mV
rms
signal at 1 kHz.
16. Repeat step 10 for the 26 dB gain range, substituting the gain parameter with 26 and the
referenceVoltage parameter with 0.315.
Note
All ranges must be adjusted for gain for the calibration to be valid.
Committal
17. Call
DAQmxCloseExtCal
(DAQmx Close External Calibration VI) with the following
parameters to finish the calibration adjustment:
calHandle:
myCalHandle
action:
DAQmx_Val_Action_Commit
or
DAQmx_Val_Action_Cancel
Use the action
cancel
if there has been any error during the calibration or if you do not
want to save the new calibration constants in the device EEPROM.
Use the action
commit
if you want to save the new calibration constants in the device
EEPROM.
The device is now calibrated with respect to the external sources.
Minimum Cabling Method
Complete the following performance adjustment procedures to adjust the PXIe-4481 using the
“minimum cabling” method. To view a programming block diagram that provides an overview
of this adjustment procedure, go to
ni.com/info
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