Verifying Voltage Excitation Limits - National Instruments SCXI-1121 Calibration Procedure

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2. Set the channel gain on all channels to the gain you want to test,
starting with the smallest gain available for the SCXI-1121. Refer to
Table 12 for available gains.
3. Set the channel filter for all channels on the SCXI-1121 to 10 kHz.
4. Connect the calibrator to the analog input channel you are testing,
starting with channel 0. If you do not have an SCXI terminal block
such as the SCXI-1320, refer to Table 13 to determine the pins on the
96-pin front connector that correspond to the positive and negative
inputs of the specified channel. For example, the positive input for
channel 0 is pin A32, which is labeled CH0+. The negative input for
channel 0 is pin C32, which is labeled CH0–.
5. Set the DMM to voltage mode, and connect it to the output of the same
channel to which the calibrator was connected in step 4. Refer to
Table 14 to determine the pins on the 50-pin rear connector that
correspond to the positive and negative outputs for the specified
channel. For example, the positive output for channel 0 is pin 3, which
is labeled CH 0+. The negative output for channel 0 is pin 4, which is
labeled CH 0–.
6. Set the calibrator voltage to the value specified by the Test Point entry
listed in Table 12.
7. Read the resulting output voltage on the DMM. If the output voltage
result falls between the Upper Limit and the Lower Limit values, the
SCXI-1121 passed the test.
8. Repeat steps 4 through 7 for the remaining test points.
9. Repeat steps 4 through 8 for the remaining analog input channels.
10. Repeat steps 2 through 9 for the remaining gain and filter values
specified in Table 12.
You have completed verifying the analog input offsets. If any of your
measurements fall outside the test limits listed in Table 12, adjust the
SCXI-1121 as described in the

Verifying Voltage Excitation Limits

Complete the following steps to verify the voltage excitation limits:
Connect a 120 Ω resistor to the output of the excitation channel you are
1.
testing, starting with excitation channel 0.
If you have a terminal block such as the SCXI-1320, the excitation
channel connections are marked on the terminal block. If you do not
have a terminal block, refer to Table 13 for connection information.
2. Configure the excitation channel to the 3.333 V level.
3. Set the DMM to voltage mode, and connect the DMM leads to the
excitation output as closely as possible to the resistor body.
Adjusting Analog Input Offsets
11
section.
SCXI-1121 Calibration Procedure