National Instruments NI 4070/4072 6 1/2-Digit FlexDMM - page 12

NI 4070/4072 Calibration Procedure 12 ni.com

34. Set the input resistance of the NI 4070/4072 to >10 GΩ by calling

niDMM_SetAttributeViReal64 with the following parameters:

•Attribute_ID = NIDMM_ATTR_INPUT_RESISTANCE

•Attribute_Value = NIDMM_VAL_GREATER_THAN_10_GIGAOHM

35. Call niDMM_Read. Subtract the previously stored 100mV >10 GΩ

mode offset from this measurement, and verify that the result falls

between the limits listed in Table15.

36. Set the input resistance of the NI 4070/4072 to 10 MΩ by calling

niDMM_SetAttributeViReal64 with the following parameters:

•Attribute_ID = NIDMM_ATTR_INPUT_RESISTANCE

•Attribute_Value = NIDMM_VAL_10_MEGAOHM

37. Call niDMM_Read. Subtract the previously stored 100mV 10 MΩ

mode offset from this measurement and verify that the result falls

between the limits listed in Table15.

38. Output –100 mV on the calibrator with the range locked to 2.2 V.

This range prevents a 50Ω calibrator output resistance from creating

avoltage divider with the internal resistance of the NI 4070/4072.

39. Set the input resistance of the NI 4070/4072 to >10 GΩ by calling

niDMM_SetAttributeViReal64 with the following parameters:

•Attribute_ID = NIDMM_ATTR_INPUT_RESISTANCE

•Attribute_Value = NIDMM_VAL_GREATER_THAN_10_GIGAOHM

40. Call niDMM_Read. Subtract the previously stored 100mV >10 GΩ

mode offset from this measurement, and verify that the result falls

between the limits listed in Table15.

41. Set the input resistance of the NI 4070/4072 to 10 MΩ by calling

niDMM_SetAttributeViReal64 with the following parameters:

•Attribute_ID = NIDMM_ATTR_INPUT_RESISTANCE

•Attribute_Value = NIDMM_VAL_10_MEGAOHM

42. Call niDMM_Read. Subtract the previously stored 100mV 10 MΩ

mode offset from this measurement and verify that the result falls

between the limits listed in Table15.

43. Output 1 V on the calibrator.

44. Call niDMM_ConfigureMeasurement with the following

parameters:

•Function = NIDMM_VAL_DC_VOLTS

•Range = 1

•Resolution = 1e–6

Contents

Main CALIBRATION PROCEDURE NI 4070/4072 6-Digit FlexDMM Contents Conventions Software Requirements Documentation Requirements Calibration Function Reference Password Calibration Interval Test Equipment Required Test Equipment Requirements for All NI 4070/4072 Devices Additional Requirements for the NI 4072 Optional Test Equipment Test Conditions Calibration Procedures Initial Setup Verification Procedures Verifying DC Voltage Page NI 4070/4072 Calibration Procedure 10 ni.com Figure 1. Cable Connections for Voltage and 2-Wire Resistance niDMM_SetAttributeViReal64 with the following parameters: Attribute_ID = Attribute_Value = NIDMM_VAL_GREATER_THAN_10_GIGAOHM 1 NI4070/4072 2 Fluke 5700A/5720A Calibrator 3 Fluke 5440 Cable Table 1. Fluke 5440 Cable Connections BananaPlug Connector (NI4070/4072) Banana Plug Color (Fluke 5440Cable) Page Page Page Page Verifying AC Voltage Page Page Page Page Page Page Verifying 4-Wire Resistance Page Verifying 2-Wire Resistance Page Page Page Page Page Verifying DC Current Page Page Verifying AC Current Verifying Frequency Page Page Verifying Capacitance and Inductance (NI 4072 Only) Page Page Page Adjustment Procedures Setting Up the Test Equipment Adjusting DC Voltage and Resistance Page Page Page Page Page Adjusting AC Voltage (AC- and DC-Coupled) Modes Page Page Page Table 13. niDMM_CalAdjustACFilter Parameters (Continued) Adjusting Current Modes Page Page Adjusting Capacitance and Inductance (NI 4072 Only) Page Completing the Adjustment Procedures Verification Limits DC Voltage AC Voltage Table 16. NI 4070/4072 AC Voltage Verification Limits Table 15. NI 4070/4072 DC Voltage Verification Limits (Continued) Table 16. NI 4070/4072 AC Voltage Verification Limits (Continued) 4-Wire Resistance Note Tolerances are provided for 4-wire resistance instead of absolute limits because the limits depend on the actual resistance value output by your calibrator. 2-Wire Resistance Note Tolerances are provided for 2-wire resistance instead of absolute limits because the DC Current AC Current Table 19. NI 4070/4072 DC Current Verification Limits Table 20. NI 4070/4072 AC Current Verification Limits Table 18. NI 4070/4072 2-Wire Resistance Verification Tolerances (Continued) Frequency Capacitance and Inductance Note Because the actual capacitance verification values can differ from the following values, Table22 provides tolerances that correspond to the NI 4072 accuracy specifications Table 21. Frequency Limits Appendix A: Calibration Options Page Figure 4. Verification Procedures Flowchart NI 4070/4072 Calibration Procedure 66 ni.com Figure 5. Adjustment Procedures Flowchart National Instruments Corporation 67 NI 4070/4072 Calibration Procedure Where to Go for Support