SCXI-1141/1142/1143 Calibration Procedure
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Test Conditions
Follow these guidelines to optimize the connections and the environment
during calibration:
•
Keep connections to the SCXI terminal block and the rear connector of
the SCXI module short. Long cables and wires act as antennae, picking
up extra noise and thermal offsets that can affect measurements.
•
Use shielded copper wire for all cable connections to the
SCXI-1141/1142/1143. Use twisted-pair wire to reduce noise.
•
Maintain the temperature between 18 and 28 °C.
•
Keep relative humidity below 80%.
•
Allow a warm-up time of at least 15 minutes for the SCXI module and
30 minutes for the DAQ device to ensure the measurement circuitry is
at a stable operating temperature.
Calibration Procedure
This section provides step-by-step instructions for calling the appropriate
calibration functions.
The steps used in the calibration procedure are as follows:
1.
Setting up the SCXI-1141/1142/1143 for testing.
2.
Verifying the existing operation of the SCXI-1141/1142/1143 to
determine whether it is operating within its test limits.
3.
Adjusting the offset and gain errors using a known external voltage
source.
4.
Verifying that the SCXI-1141/1142/1143 is operating within its test
limits after adjustments.
Setting up the SCXI-1141/1142/1143 for Calibration
Complete the following steps, while referring to Figure 1 to set up the
SCXI-1141/1142/1143 for calibration.
1.
Make sure all components involved in the calibration procedure are
powered-off.
2.
Assemble the SCXI-1141/1142/1143, chassis, terminal block, and
DAQ device as shown in Figure 1. The SCXI module you are
calibrating must be connected directly to the DAQ device.
3.
Power on the SCXI chassis and the external computer.
4.
Make sure that all the appropriate driver and application software is
installed.
