National Instruments NI 6703, Процедура калибровки

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© National Instruments Corporation 7 NI 6703/6704 Calibration Procedure for Traditional NI-DAQ
3. Place the DMM in current mode.
4. Call
AO_VWrite
to generate 0.1 mA on current channel 16. Set the
following parameters:
• chan : 16
• voltage : 0.1
5. Compare the resulting value shown by the DMM to the upper and
lower limits listed in Table 2 in the
Specifications section. If the value
is between these limits, the device passes the test.
6. Call
AO_VWrite
to generate 20.0 mA on current channel 16. Set the
following parameters:
• chan : 16
• voltage : 20.0
7. Compare the resulting value shown by the DMM to the upper and
lower limits listed in Table 2 in the
Specifications section. If the value
is between these limits, the device passes current verification.
8. Disconnect the DMM from the NI 6704.
You have now verified the current output of the NI 6704.
Adjusting the NI 6703/6704
At the end of each calibration procedure, new constants are stored in
the user calibration area of the NI 6703/6704, ensuring that the device
stores a permanent record of the calibration constants. Storing the
calibration constants here also ensures that the constants automatically load
when the NI 6703/6704 is powered on.
Adjusting Voltage Output
For the voltage outputs, you need to make offset and gain adjustments.
Adjust offsets first, followed by gains. Adjust offset and gain again to
ensure accuracy. This second set of offset and gain adjustments is
necessary because a large initial change in one of the calibration channels
can affect the accuracy of the other calibration channel.
The following table lists the offset and gain channel numbers.
Calibration Channel NI 6703 Channel Numbers NI 6704 Channel Numbers
Voltage Offset 16 32
Voltage Gain 17 34