National Instruments 4065, Calibration Procedure, Page: 5 / 93

© National Instruments Corporation 5 NI 4065 Calibration Procedure
• Power on and warm up the NI PXI/PCI/PCIe-4065 for at least
30 minutes and the NI USB-4065 for at least 50 minutes before
beginning this calibration procedure.
• Maintain an ambient temperature of 23 ±1 °C.
• Maintain an ambient relative humidity of less than 60%.
• Allow the calibrator to settle fully before taking any measurements.
Consult the Fluke 5700A/5720A user documentation for instructions.
• Allow the thermal EMF enough time to stabilize when you change
connections to the calibrator or the NI 4065. The suggested time
periods are stated where necessary throughout this document.
• Keep a shorting bar connected between the V GUARD and
GROUND binding posts of the calibrator at all times.
• Clean any oxidation from the banana plugs on the Fluke 5440 cables
before plugging them into the binding posts of the calibrator or the
banana plug connectors of the NI 4065. Oxidation tarnishes the copper
banana plugs so they appear dull rather than shiny. Oxidation leads to
greater thermal EMF.
• Keep the blue banana plugs on the Fluke 5440 cables connected to the
V GUARD binding post of the calibrator at all times.
• Prevent the cables from moving or vibrating by taping or strapping
them to a nonvibrating surface. Movement or vibration causes
triboelectric effects that can result in measurement errors.
Calibration Procedures
The calibration process includes the following steps:
1. Initial Setup —Set up the test equipment.
2. Verification Procedures —Verify the existing operation of the device.
This step confirms whether the device is operating within its specified
range prior to calibration. Figure 9 shows the procedural flow for
verification.
3. Adjustment Procedures —Perform an external adjustment of the device
that adjusts the calibration constants with respect to a known voltage
source. Figure 10 shows the procedural flow for adjustment.
4. Reverification—Repeat the verification procedure to ensure the device
is operating within its specifications after adjustment.
These steps are described in more detail in the following sections and in
Appendix A: Calibration Options .
Note Throughout the procedure, refer to the C/C++ function call parameters for the
LabVIEW input values.