National Instruments NI 6731, Процедура калибровки

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© National Instruments Corporation 9 NI 6711/6713/6731/6733 Calibration Procedure
4. To find out the date of the last calibration, call
Get_Cal_Date
, which
is included in the
ni671x.dll
. CalDate stores the date when the
device was last calibrated.
5. Set the calibrator to output a voltage of 5.0 V.
6. Call
Calibrate_E_Series
with the following parameters set as
indicated:
• calOP set to
ND_EXTERNAL_CALIBRATE
• setOfCalConst set to
ND_USER_EEPROM_AREA
• calRefVolts set to
5.0
Note If the voltage supplied by the source does not maintain a steady 5.0 V, you receive
an error.
7. Call
Copy_Const
to copy the new calibration constants to the
factory-protected portion of the EEPROM. This function also updates
the calibration date.
8. Disconnect the calibrator from the device.
The device is now adjusted with respect to the external source. After
the device is adjusted, you can verify the AO operation by repeating the
Verifying Analog Output section.
Specifications
The following tables are accuracy specifications to use when verifying and
adjusting the NI 6711/6713/6731/6733. The tables show the specifications
for 1-year and 24-hour calibration intervals.
Using the Tables
The following definitions describe how to use the specification tables in
this section.
Range
Range refers to the maximum allowable voltage range of an input or output
signal. For example, if a device is configured in bipolar mode with a range
of 20 V, the device can sense signals b10 and –10 V.
Polarity
Polarity refers to the positive and negative voltages of the input signal that
can be read. Bipolar means the device can read both positive and negative
voltages. Unipolar means that the device can read only positive voltages.