National Instruments SC Express PXIe-4309, Процедура калибровки

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PXIe-4309 Calibration Procedure | © National Instruments | 13
Adjustment
An adjustment is required at least once every two years to warrant the published specifications
for the next calibration interval. An adjustment is recommended even if the PXIe-4309
successfully passed each verification procedures within the
As-Left Limits (V) without
adjustment . Performing an adjustment procedure improves the device accuracy and resets the
calibration interval.
Upon successful completion of an adjustment procedure, the calibration constants, date, and
temperature in the device EEPROM are automatically updated.
To update the calibration date without performing an adjustment, refer to the instructions in the
EEPROM Update section.
The following procedure describes the sequence of operations required to adjust the PXIe-4309.
Depending on the terminal block used for verification, refer to step a or b for specifics about how
to connect the calibrator output to the PXIe-4309 input.
1.
Measure the PXIe-4309 Internal Reference.
Note Keep the test lead set loop area as small as possible.
a. CAL-4309 — Use a low thermal EMF banana-to-banana test lead set to connect the
internal reference of the PXIe-4309 to the DMM input as shown in Figure 5.
i.
Attach the CAL-4309 terminal block to the PXIe-4309 module.
ii. Tighten the mounting screw at the top of the terminal block to secure the terminal
block to the module.
iii. Wait ten minutes for the thermal EMF to stabilize.
Table 5. AI Setup for DC Voltage Verification
Configuration Value
Physical Channels
dev1/aix
, where
x
refers to the channel number.
Input Range Input range from Table 4
Input Terminal Configuration Differential
Rate 10 S/s
Sample Mode Finite
Samples per Channel 11
Auto Zero Every Sample
Chopping Disabled