6703/6704 Calibration Procedure
10
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3.
Place the DMM in voltage mode.
4.
Run
AO_VWrite
with
chan
set to 0 and
voltage
set to 0.0. This will
output 0.0 V on voltage channel 0.
5.
Run
AO_VWrite
with the channel set to the voltage offset channel.
Adjust the
voltage
parameter until the DMM reads as close to 0.0 V as
possible. The value you write to the voltage offset channel will be close
to 0.0 V. Increasing the voltage value will lower the magnitude of the
voltage seen on voltage channel 0. Decreasing the voltage value will
increase the magnitude of the voltage seen on voltage channel 0.
6.
Run
AO_VWrite
with
chan
set to 0 and
voltage
set to 10.0. This will
output 10.0 V on voltage channel 0.
7.
Run
AO_VWrite
with the channel set to the voltage gain channel.
Adjust the
voltage
parameter until the DMM reads as close to 10.0 V
as possible. The value you write to the voltage gain channel will be
close to 10.0 V. Increasing the voltage value will lower the magnitude
of the voltage on voltage channel 0. Decreasing the voltage value will
increase the magnitude of the voltage on voltage channel 0.
You have now calibrated the voltage output.
Calibrating Current Output (6704 Only)
For the current outputs, you need to make offset and gain adjustments. You
perform offset adjustment first, followed by gain adjustment. You will then
perform both offset and gain adjustment again to ensure proper 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.
You will need a DMM to measure the current output. Make sure that you
have read the
Equipment and Other Test Requirements
section covered
previously, and follow these steps to adjust current output:
1.
Run
Set_DAQ_Device_Info
with
infoType
set to
ND_CALIBRATION_ENABLE
and
infoValue
set to
ND_YES
. This step
configures the board so you can access the calibration channels.
2.
Connect the DMM to the board as shown in the following table.
Calibration Channel
6704 Channel Numbers
Current Offset
33
Current Gain
35
