NI 6110/6111/6115/6120 Calibration Procedure
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straightforward, as many of the VIs have the same names as the listed
function calls. Refer to the
Creating Verification and Calibration Code
section for flowcharts detailing the code used at each step of the calibration
procedure.
You must follow a number of compiler-specific steps to create an
application using NI-DAQ. The
NI-DAQ User Manual for PC Compatibles
details the required steps for each of the supported compilers.
Many of the functions listed in the calibration procedure use variables that
are defined in the
nidaqcns.h
file. To use these variables, you must
include the
nidaqcns.h
file in your code. If you do not wish to use these
variable definitions, you can examine the function call listings in NI-DAQ
documentation and the
nidaqcns.h
file to determine what input values
are required.
Test Conditions
To optimize connections and test conditions during calibration, use the
following guidelines:
•
Keep connections to the device as short as possible. Long cables and
wires can act as antennae, picking up extra noise that can affect
calibration.
•
Use shielded copper wire for all cable connections to the device.
Use twisted-pair wire to eliminate noise and thermal offsets.
•
Maintain a temperature between 18 and 28 °C. To operate the device
at a specific temperature outside this range, calibrate the module at that
temperature.
•
Keep relative humidity below 80%.
•
Allow a warm-up time of at least 15 minutes for PXI/PCI/AT bus
devices and 30 minutes for PCMCIA devices to ensure that the
measurement circuitry is at a stable operating temperature.
Calibration Process
The calibration process consists of four main steps.
1.
Creating Verification and Calibration Code
2.
Verifying the Performance of the NI 6110/6111/6115/6120
—This step
determines whether the device is in specification prior to calibration.
3.
—This step adjusts the calibration constants with
respect to a known voltage source.
