National Instruments SCXI-1121 Calibration Procedure page 16

SCXI-1121 Calibration Procedure
4. Set the calibrator to output 0.0 V.
5. Adjust the output null potentiometer of the channel until the DMM
reading is 0.0 ±3.0 mV. Refer to Figure 3 for the potentiometer
location and Table 10 for the potentiometer reference designator.
Table 10. Calibration Potentiometers Reference Designators
Input Channel Number
0
1
2
3
6. Set the channel gain to a gain of 1000.0 on the channel you are
adjusting. Refer to Tables 2, 3, and 4 for more information.
7. Adjust the input null potentiometer of channel 0 until the DMM
reading is 0.0 ±6.0 mV. Refer to Figure 3 for the potentiometer
location and Table 10 for the potentiometer reference designator.
8. Repeat steps 1 through 7 for the remaining analog inputs.
You have completed adjusting the analog input offsets.
Adjusting Voltage Excitation
When you adjust the excitation channels, you should always start with the
voltage excitation and then proceed to the current excitation. Use the
voltage excitation reference as the voltage reference for the current
excitation.
Complete the following steps to adjust the voltage excitation:
Connect the 120 Ω resistor across the output of the excitation channel
1.
you are adjusting.
2. Configure the excitation channel to 3.333 V excitation level.
3. Connect the DMM leads to the excitation outputs as closely as possible
to the resistor body.
4. Adjust the excitation voltage potentiometer until the voltage reading
falls between 3.337 and 3.329 V. Refer to Figure 3 for the
potentiometer location and Table 11 for the potentiometer reference
designator.
Input Null
R02
R16
R26
R36
16
Output Null
R03
R04
R05
R06
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