National Instruments NI-9219 Calibration Procedure
  1. Manuals
  2. Brands
  3. National Instruments Manuals
  4. Measuring Instruments
  5. NI 9219
  6. Calibration procedure

National Instruments NI-9219 Calibration Procedure

Hide thumbs Also See for NI-9219:
Table of Contents

Advertisement

Quick Links

Download this manual
NI-9219

Advertisement

Table of Contents
loading
Need help?

Need help?

Do you have a question about the NI-9219 and is the answer not in the manual?

Questions and answers

Subscribe to Our Youtube Channel

Related Manuals for National Instruments NI-9219

Summary of Contents for National Instruments NI-9219

  • Page 1 NI-9219...

  • Page 2: Table Of Contents

    CALIBRATION PROCEDURE NI 9219 Français Deutsch ni.com/manuals This document contains information for calibrating the National Instruments 9219. For more information on calibration, visit ni.com/calibration Contents Software Requirements........................1 Documentation Requirements......................2 Calibration Interval ..........................2 Test Equipment ............................ 2 Test Conditions ............................ 4 Calibration Procedures.........................

  • Page 3: Documentation Requirements

    NI-DAQmx C Reference Help—This help file contains C reference and general information about measurement concepts. Calibration Interval National Instruments recommends a calibration interval of one year for the NI 9219. You should adjust the recommended calibration interval based on the measurement accuracy demands of your application. Test Equipment National Instruments recommends that you use the equipment in Table 1 for calibrating the NI 9219.
  • Page 4 TCR: 10 ppm/°C Half-Bridge Accuracy Resistor values: 1 k ± 1% (x2) TCR: 10 ppm/°C Full-Bridge Accuracy Resistor values: 10 k ± 1% (x2) cDAQ NI cDAQ-9178 — Chassis Connection NI 9972 — Accessory © National Instruments Corporation NI 9219 Calibration Procedure...

  • Page 5: Test Conditions

    Test Conditions The following setup and environmental conditions are required to ensure the NI 9219 meets published specifications. • Keep connections to the device as short as possible. Long cables and wires act as antennae, picking up extra noise that can affect measurements. •...

  • Page 6: Verification

    Positive excitation or input signal Positive input signal EX–/LO Negative excitation or input signal Negative input signal Depending on the mode, terminals 3 and 5 are either the excitation signals or the input signals. © National Instruments Corporation NI 9219 Calibration Procedure...

  • Page 7: Voltage Accuracy Verification

    Table 3. NI 9219 Terminal Assignments by Mode Terminal Mode Voltage T– — — Current T– — — 4-Wire Resistance T– EX– 2-Wire Resistance T– — — Thermocouple T– — — 4-Wire RTD T– EX– 3-Wire RTD T– — EX– Quarter-Bridge T–...
  • Page 8 Maximum Lower Limit Upper Limit Location Value (V) –60 –0.03670 0.03670 –0.00100 0.00100 –48 –0.03670 0.03670 –15 –0.00980 0.00980 –0.00080 0.00080 –12 –0.00980 0.00980 –4 –0.00300 0.00300 –0.00060 0.00060 –3.2 –0.00300 0.00300 © National Instruments Corporation NI 9219 Calibration Procedure...

  • Page 9: Thermocouple Accuracy Verification

    Table 5. NI 9219 Verification Test Limits for Voltage Accuracy (Continued) Range Test Point 1–Year Limits Minimum Maximum Lower Limit Upper Limit Location Value (V) –1 0.80 –0.000260 0.000260 0.00 –0.000014 0.000014 –0.80 –0.000260 0.000260 –0.125 0.125 0.10 –0.000041 0.000041 0.00 –0.000010 0.000010...
  • Page 10 Table 7 for each channel, but you can save time by verifying only the values and channels used in your application. 13. Disconnect the source and the DMM from the device. © National Instruments Corporation NI 9219 Calibration Procedure...

  • Page 11: Current Accuracy Verification

    Current Accuracy Verification Complete the following steps to verify the current accuracy of an NI 9219. Connect the NI 9219 to the DMM and source as shown in Figure 4. AMPS I– Source HI (3) Ch 0 LO (5) HI (3) Ch 1 LO (5) HI (3)

  • Page 12: 2-Wire Resistance Accuracy Verification

    Configure the DMM for a 4-wire resistance measurement in the appropriate range according to the appropriate test point from Table 11. Enable Auto Zero on the DMM. Acquire a resistance reading with the DMM. Record this measurement as  © National Instruments Corporation NI 9219 Calibration Procedure...

  • Page 13: Quarter-Bridge Accuracy Verification

    Disconnect the DMM from the resistor to ensure that the terminals on the DMM do not interfere with the resistor while the NI 9219 makes measurements. Clear the task. Create an AI resistance channel on the NI 9219. Configure the channel according to Table 10. Table 10.
  • Page 14 Table 13. 12. Perform the following calculation using the recorded  and  values. channel   Accuracy – channel © National Instruments Corporation NI 9219 Calibration Procedure...

  • Page 15: 4-Wire Resistance Accuracy Verification

    13. Compare the calculation result to the Upper Limit and Lower Limit values in Table 13. Table 13. NI 9219 Verification Test Limits for Quarter-Bridge Accuracy Range Test Point 1–Year Limits Lower Limit Upper Limit Mode Min () Max () Location Value ()

  • Page 16: 4-Wire Rtd Accuracy Verification

    DMM as close as possible to the same point that the sense leads of the NI 9219 (HI and LO) connect to the resistor to ensure that the DMM reference measurements include the same lead wire resistance as the NI 9219 4-wire measurements. © National Instruments Corporation NI 9219 Calibration Procedure...
  • Page 17 EX+ (3) Ω HI (4) Ch x TestPoint EX– (5) Ω SENSE LO (6) NI 9219 Figure 8. 4-Wire RTD Accuracy Verification Connections to the NI 9219 Create an AI voltage channel in the 1 V range on the NI 9219. Commit the task to place the NI 9219 in voltage mode.

  • Page 18: 3-Wire Rtd Accuracy Verification

    Configure the DMM for a 4-wire resistance measurement in the appropriate range according to the test point from Table 19. Enable Auto Zero on the DMM. Acquire a resistance reading with the DMM. Record this measurement as  TopHalfDMM © National Instruments Corporation NI 9219 Calibration Procedure...
  • Page 19 Reconnect the DMM as shown in Figure 10. To minimize mismatch between the NI 9219 and the DMM, connect the  and  leads of the DMM as close as possible to the same point where senseHI the LO lead from the NI 9219 connects to the resistor and the  and the ...

  • Page 20: Half-Bridge Accuracy Verification

    Connect the NI 9219 to DMM1 as shown in Figure 11. DMM1 EX+ (3) HI (4) Ch x EX– (5) NI 9219 Figure 11. Half-Bridge Accuracy Verification Connections to the NI 9219 (Configuration 1) © National Instruments Corporation NI 9219 Calibration Procedure...
  • Page 21 Create an AI bridge V/V channel on the NI 9219. Configure the channel according to Table 20. Table 20. NI 9219 Configuration for Half-Bridge Accuracy Verification Measurement Excitation Excitation Bridge ADC Timing Sample Type Source Value Config Mode Timing Type Half-Bridge –0.5 Internal...
  • Page 22 Configure DMM1 for a voltage measurement in the 10 V range. 10. Enable Auto Zero on DMM1. 11. Configure DMM2 for a voltage measurement in the 10 V range. 12. Enable Auto Zero on DMM2. © National Instruments Corporation NI 9219 Calibration Procedure...
  • Page 23 13. Acquire voltage measurements with both DMMs. Perform the following calculation using the two DMM measurements. DMM2 Ratio ---------------- DMM1 14. Acquire 20 bridge readings with the NI 9219. Record the average of the readings as Ratio channel Note Perform the DMM measurements and the NI 9219 measurements as simultaneously as possible in order to reduce error from drift in the resistors.

  • Page 24: Full-Bridge Accuracy Verification

    Connect the leads of DMM1 as close as possible to the terminals on the NI 9219. • Connect the HI lead of DMM2 as close as possible to the same point that the HI lead of the NI 9219 connects to the resistor network. © National Instruments Corporation NI 9219 Calibration Procedure...
  • Page 25 • Connect the LO lead of DMM2 as close as possible to the same point that the LO lead of the NI 9219 connects to the resistor network. V– Source 10 kΩ ± 1% DMM1 TestPoint DMM2 10 kΩ ± 1% EX+ (3) HI (4) Ch x...

  • Page 26: Adjustment

    EEPROM of the NI 9219. Note National Instruments recommends a complete adjustment of your device to renew the calibration interval. However, if you do not want to perform an adjustment, you can update the calibration date and onboard calibration temperature without making any adjustments by calling only DAQmx Initialize External Calibration VI, DAQmx Set Temperature C Series Calibration, and DAQmx Close External Calibration VI.

  • Page 27: Voltage And Thermocouple Accuracy Adjustment

    Voltage and Thermocouple Accuracy Adjustment Complete the following steps to adjust the voltage accuracy and thermocouple accuracy of the NI 9219. Connect the NI 9219 to the DMM and source as shown in Figure 2. Open a calibration session to your device using the DAQmx Initialize External Calibration VI. The default password is LabVIEW Block Diagram NI-DAQmx Function Call...
  • Page 28 Set the source to a reference value determined by the array of adjustment points. Configure the DMM for a voltage measurement. Enable Auto Zero on the DMM. Acquire a voltage reading with the DMM. © National Instruments Corporation NI 9219 Calibration Procedure...
  • Page 29 10. Acquire a voltage reading with the NI 9219 using the NI 9219 instance of the DAQmx Adjust C Series Calibration VI. LabVIEW Block Diagram NI-DAQmx Function Call Call with the following DAQmxAdjust9219Cal parameters: calHandle: calHandle channelName: cDAQ1Mod8/aix value: The DMM reading. *x refers to the channel number 11.

  • Page 30: Current Accuracy Adjustment

    Place all channels on the NI 9219 in current mode using the NI 9219 instance of the DAQmx Setup C Series Calibration VI. LabVIEW Block Diagram NI-DAQmx Function Call Call with the following DAQmxSetup9219Cal parameters: rangeMin: –0.025 rangeMax: 0.025 calHandle: calHandle channelName: i0:3 cDAQ1Mod8/a measType: DAQmx_Val_Current bridgeConfig: DAQmx_Val_NoBridge © National Instruments Corporation NI 9219 Calibration Procedure...
  • Page 31 Set up the signal acquisition using the NI 9219 instance of the DAQmx Setup C Series Calibration VI. LabVIEW Block Diagram NI-DAQmx Function Call Call with the following DAQmxSetup9219Cal parameters: rangeMin: –0.025 rangeMax: 0.025 calHandle: calHandle channelName: cDAQ1Mod8/a measType: DAQmx_Val_Current bridgeConfig: DAQmx_Val_NoBridge * x refers to the channel number...
  • Page 32 Call with the following DAQmxAdjust9219Cal parameters: calHandle: calHandle channelName: cDAQ1Mod8/a value: The DMM reading. *x refers to the channel number 12. Repeat steps 7 through 11 for every value in the array. © National Instruments Corporation NI 9219 Calibration Procedure...

  • Page 33: 4-Wire And 2-Wire Resistance Accuracy Adjustment

    13. Compute and save the adjustment to the EEPROM using the DAQmx Close External Calibration VI. This VI also saves the date, time, and temperature of the adjustment to the EEPROM. LabVIEW Block Diagram NI-DAQmx Function Call Call with the following DAQmxCloseExtCal parameters: calHandle:...
  • Page 34 Input the external temperature using the DAQmx Set Temperature C Series Calibration VI. LabVIEW Block Diagram NI-DAQmx Function Call Call with the DAQmxCSeriesSetCalTemp following parameters: calHandle: calHandle temperature: The external temperature value in degrees Celsius. © National Instruments Corporation NI 9219 Calibration Procedure...
  • Page 35 Obtain an array of the recommended calibration resistances for your device using the NI 9219 instance of the DAQmx Get C Series Calibration Adjustment Points VI. LabVIEW Block Diagram NI-DAQmx Function Call Call with DAQmxGet9219CalAdjustPoints the following parameters: calHandle: calHandle adjustmentPoints: An array of reference values for the DAQmx Adjust Calibration VI.
  • Page 36 Calibration VI. LabVIEW Block Diagram NI-DAQmx Function Call Call with the following DAQmxSetup9219Cal parameters: rangeMin: rangeMax: 1050, 10500 calHandle: calHandle channelName: cDAQ1Mod8/a measType: DAQmx_Val_Resistance bridgeConfig: DAQmx_Val_NoBridge x refers to the channel number © National Instruments Corporation NI 9219 Calibration Procedure...
  • Page 37 12. Acquire a 4-wire resistance reading with the NI 9219 using the NI 9219 instance of the DAQmx Adjust C Series Calibration VI. LabVIEW Block Diagram NI-DAQmx Function Call Call with the following DAQmxAdjust9219Cal parameters: calHandle: calHandle channelName: cDAQ1Mod8/a value: The DMM reading. x refers to the channel number 13.

  • Page 38: 4-Wire Rtd, 3-Wire Rtd, And Quarter-Bridge Accuracy Adjustment

    DAQmxInitExtCal parameters: deviceName: The name of the device you want to calibrate. This name can be found under Devices and Interfaces in Measurements & Automation Explorer. password: calHandle: &calHandle © National Instruments Corporation NI 9219 Calibration Procedure...
  • Page 39 Place the NI 9219 channel in RTD mode using the NI 9219 instance of the DAQmx Setup C Series Calibration VI. LabVIEW Block Diagram NI-DAQmx Function Call Call with the following DAQmxSetup9219Cal parameters: rangeMin: rangeMax: 505, 5050 calHandle: calHandle channelName: cDAQ1Mod8/a measType: DAQmx_Val_Temp_RTD...
  • Page 40 NI-DAQmx Function Call Call with the following DAQmxSetup9219Cal parameters: rangeMin: –1 rangeMax: calHandle: calHandle channelNames: cDAQ1Mod8/aix measType: DAQmx_Val_Voltage bridgeConfig: DAQmx_Val_NoBridge x refers to the channel number Configure the DMM for a 4-wire resistance measurement. © National Instruments Corporation NI 9219 Calibration Procedure...
  • Page 41 Enable Auto Zero on the DMM. Acquire a resistance reading with the DMM. 10. Disconnect the DMM from the resistors and NI 9219. 11. Set up the signal acquisition using the NI 9219 instance of the DAQmx Setup C Series Calibration VI.
  • Page 42 DAQmxCloseExtCal parameters: calHandle: calHandle action: DAQmx_Val_Action_Commit 16. Disconnect the resistor and the DMM from the device. 17. Repeat steps 1 through 16 for each channel on the NI 9219. © National Instruments Corporation NI 9219 Calibration Procedure...

  • Page 43: Half-Bridge Accuracy Adjustment

    Half-Bridge Accuracy Adjustment Complete the following steps to adjust the half-bridge accuracy of the NI 9219. Connect the NI 9219 to DMM1 as shown in Figure 11. Open a calibration session to your device using the DAQmx Initialize External Calibration VI. The default password is LabVIEW Block Diagram NI-DAQmx Function Call...
  • Page 44 11. Configure DMM1 for a voltage measurement in the 10 V range. 12. Enable Auto Zero on DMM1. 13. Configure DMM2 for a voltage measurement in the 10 V range. 14. Enable Auto Zero on DMM2. © National Instruments Corporation NI 9219 Calibration Procedure...
  • Page 45 15. Acquire voltage measurements with both DMMs. Perform the following calculation using the two DMM measurements. DMM2 Ratio ---------------- DMM1 16. Acquire a bridge reading with the NI 9219 using the NI 9219 instance of the DAQmx Adjust C Series Calibration VI. LabVIEW Block Diagram NI-DAQmx Function Call Call...

  • Page 46: Full-Bridge Accuracy Adjustment

    LabVIEW Block Diagram NI-DAQmx Function Call Call with the following DAQmxSetup9219Cal parameters: rangeMin: –0.0078125, –0.0625 rangeMax: 0.0078125, 0.0625 calHandle: calHandle channelName: cDAQ1Mod8/a measType: DAQmx_Val_Bridge bridgeConfig: DAQmx_Val_FullBridge x refers to the channel number © National Instruments Corporation NI 9219 Calibration Procedure...
  • Page 47 Input the external temperature using the DAQmx Set Temperature C Series Calibration VI. LabVIEW Block Diagram NI-DAQmx Function Call Call with the DAQmxCSeriesSetCalTemp following parameters: calHandle: calHandle temperature: The external temperature value in degrees Celsius. Obtain an array of the recommended calibration voltages for your device using the NI 9219 instance of the DAQmx Get C Series Calibration Adjustment Points VI.
  • Page 48 19. Repeat steps 10 through 18 for each full-bridge mode on the NI 9219. 20. Disconnect the DMMs and the resistors from the device. 21. Repeat steps 1 through 20 for each channel on the NI 9219. © National Instruments Corporation NI 9219 Calibration Procedure...

  • Page 49: Accuracy Under Calibration Conditions

    The NI 9219 is now calibrated with respect to your external source. After performing the Adjustment Procedure, repeat the Verification Procedure to re-verify the accuracy of the module. Accuracy Under Calibration Conditions The following accuracy table is valid for calibration under the following conditions: •...

  • Page 50: Where To Go For Support

    National Instruments corporate headquarters is located at 11500 North Mopac Expressway, Austin, Texas, 78759-3504. National Instruments also has offices located around the world to help address your support needs. For telephone support in the United States, create your service request at ni.com/...

Table of Contents