National Instruments NI 6703, Процедура калибровки

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© National Instruments Corporation 9 NI 6703/6704 Calibration Procedure for Traditional NI-DAQ
because a large initial change in one of the calibration channels can affect
the accuracy of the other calibration channel. Refer to the offset and gain
channel numbers in the following table.
To adjust current output, complete the following steps:
1. Call
Set_DAQ_Device_Info
to configure the NI 6704 so you can
access the calibration channels. Set the following parameters:
• infoType :
ND_CALIBRATION_ENABLE
• infoValue :
ND_YES
2. Connect the DMM to the NI 6704 as shown in the following table.
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. Call
AO_VWrite
with the channel set to the current offset channel.
Adjust the voltage parameter until the DMM reads as close to 0.1 mA
as possible. The value you write to the current offset channel is close
to 0.01 mA. Increasing the voltage value lowers the magnitude of the
current on current channel 16. Decreasing the voltage value increases
the magnitude of the current on current channel 16.
6. Call
AO_VWrite
to generate 20.0 mA on current channel 16. Set the
following parameters:
• chan : 16
• voltage : 20.0
Calibration Channel NI 6704 Channel Numbers
Current Offset 33
Current Gain 35
Signal Name Description NI 6704 Output DMM Input
ICH16 Current Channel 16 Pin 67 High
AGND16 Analog Ground 16 Pin 68 Low