National Instruments 9212 Manual

CALIBRATION PROCEDURE
NI 9212
This document contains the verification and adjustment procedures for the NI 9212. For more
information about calibration solutions, visit ni.com/calibration.
Note Refer to the NI TB-9212 Calibration Procedure on ni.com/manuals for
instructions on calibrating the NI TB-9212.
Contents
Software.................................................................................................................................... 2
Documentation.......................................................................................................................... 2
Test Equipment......................................................................................................................... 3
Connecting the NI 9212.................................................................................................... 4
Test Conditions......................................................................................................................... 5
Initial Setup............................................................................................................................... 5
Verification ............................................................................................................................... 6
Voltage Verification ......................................................................................................... 6
CJC Verification ............................................................................................................... 8
Adjustment................................................................................................................................ 11
Voltage Adjustment .......................................................................................................... 11
CJC Adjustment................................................................................................................ 12
EEPROM Update ..................................................................................................................... 14
Reverification ........................................................................................................................... 14
Accuracy Under Calibration Conditions .................................................................................. 14
Worldwide Support and Services ............................................................................................. 15

2|ni.com |NI 9212 Calibration Procedure
Software
Calibrating the NI 9212 requires the installation of NI-DAQmx 15.1 or later on the calibration
system. You can download NI-DAQmx from ni.com/downloads. NI-DAQmx supports
LabVIEW, LabWindows™/CVI™, ANSI C, and .NET. When you install NI-DAQmx, you only
need to install support for the application software that you intend to use.
Documentation
Consult the following documents for information about the NI 9212, NI-DAQmx, and your
application software. All documents are available on ni.com and help files install with the
software.
NI cDAQ-9174/9178 Quick Start
NI-DAQmx installation and hardware setup
NI 9212 with NI TB-9212 Getting Started Guide
NI 9212 with NI TB-9212 specific information
NI 9212 with NI TB-9212 Datasheet
NI 9212 with NI TB-9212 specifications and calibration interval
NI-DAQmx Readme
Operating system and application software support in NI-DAQmx
LabVIEW Help
LabVIEW programming concepts and reference information about NI-DAQmx
VIs and functions
NI-DAQmx C Reference Help
Reference information for NI-DAQmx C functions and NI-DAQmx C properties
NI-DAQmx .NET Help Support for Visual Studio
Reference information for NI-DAQmx .NET methods and NI-DAQmx .NET
properties, key concepts, and a C enum to .NET enum mapping table

NI 9212 Calibration Procedure |© National Instruments |3
Test Equipment
Table 1 lists the equipment recommended for the performance verification and adjustment
procedures. If the recommended equipment is not available, select a substitute using the
requirements listed in Table 1.
Table 1. Recommended Equipment
Equipment
Recommended
Model Where Used Requirements
Calibrator Fluke 5522A
locked in the
3.3 V range
Vo l t a g e
Verification,
Vo l t a g e
Adjustment,
CJC
Adjustment
A high-precision voltage source with
an accuracy of ≤70 ppm when
sourcing up to 50 µA.
Fluke 5522A CJC
Verification
A high-precision resistance source
with 2-wire compensation and an
accuracy of at least
• 660 ppm at 1,099.999 Ωrange,
• 18 ppm at 32,999.99 Ωrange,
• 30 ppm at 109,999.9 Ωrange.
If the resistance source does not have
2-wire compensation, the leadwire
resistance must be included in the
total resistance source accuracy.
Chassis NI cDAQ-9178 All —
Connection
Accessory
NI CAL-9212 All —
Digital
Multimeter
NI PXI-4071 CJC
Adjustment
A multiranging 7.5 digit digital
multimeter with an accuracy of at
least
• 8 ppm at 100 mV range
• 6 ppm at 10 V range

4|ni.com |NI 9212 Calibration Procedure
Connecting the NI 9212
The NI CAL-9212 eases the calibration process by providing a thermocouple connection that is
internally routed to all eight thermocouple channels, as well as input and sense connections to
two CJC channels. Refer to Figure 1 for a pinout of the NI CAL-9212.
Caution Do not connect voltages greater than 10 VDC to the NI CAL-9212.
Figure 1. NI CAL-9212 Pinout
Connect the NI CAL-9212 to the NI 9212 front connector as shown in Figure 2. Tighten the
two jackscrews on the NI CAL-9212 to hold it securely in place. Do not overtighten the
jackscrews.
Figure 2. Installing the NI CAL-9212
1 Ground Lug (on the bottom side of the NI CAL-9212 enclosure)
1 Jackscrews 2 NI CAL-9212 3 NI 9212
10VDC MAX
Low Voltage Only
C16
NI CAL-9212
A1
C1
CJC0 INPUT +
CJC0 INPUT –
CJC1 INPUT +
CJC1 INPUT –
CJC1 SENSE +
CJC1 SENSE –
CJC0 SENSE +
CJC0 SENSE –
TC –
TC +
J1
J6 J4J3
J5 J2
1
2
1
1
3

NI 9212 Calibration Procedure |© National Instruments |5
Test Conditions
The following setup and environmental conditions are required to ensure the NI 9212 meets
published specifications.
• Keep connections to the NI 9212 as short as possible. Long cables and wires act as
antennas, picking up extra noise that can affect measurements.
• Verify that all connections to the NI 9212 are secure.
• Use shielded copper wire for all cable connections to the NI 9212. Use twisted-pairs wire
to eliminate noise and thermal offsets.
• Maintain an ambient temperature of 23 °C ±5 °C. The NI 9212 temperature will be greater
than the ambient temperature.
• Keep relative humidity below 80%.
• Allow a warm-up time of at least 15 minutes to ensure that the NI 9212 measurement
circuitry is at a stable operating temperature.
Initial Setup
Refer to the NI cDAQ-9174/9178 Quick Start for information about how to install the software
and hardware and how to configure the device in Measurement & Automation Explorer (MAX).
Complete the following steps to set up the NI 9212.
1. Install NI-DAQmx.
Note Ensure that you install NI-DAQmx 15.1 or later. Calibrating the NI 9212
using NI-DAQmx 14.5 or earlier may result in inaccurate readings.
2. Make sure the NI cDAQ-9178 power source is not connected.
3. Connect the NI cDAQ-9178 to the system safety ground.
a. Attach a ring lug to a 14 AWG (1.6 mm) wire.
b. Connect the ring lug to the ground terminal on the side of the NI cDAQ-9178 using
the ground screw.
c. Attach the other end of the wire to the system safety ground.
4. Install the module in slot 8 of the NI cDAQ-9178 chassis. Leave slots 1 through 7 of the
NI cDAQ-9178 chassis empty.
5. Connect the NI cDAQ-9178 chassis to your host computer.
6. Connect the power source to the NI cDAQ-9178 chassis.
7. Launch Measurement & Automation Explorer (MAX).
8. Right-click the device name and select Self-Test to ensure that the module is working
properly.

6|ni.com |NI 9212 Calibration Procedure
Verification
The following performance verification procedures describe the sequence of operation and test
points required to verify the NI 9212. The verification procedures assume that adequate
traceable uncertainties are available for the calibration references.
Voltage Verification
Complete the following procedure to determine the As-Found status of the NI 9212.
1. Loosen the captive screws and remove the top cover from the NI CAL-9212.
2. Connect the calibrator to the NI CAL-9212, as shown in Figure 3.
Figure 3. Voltage Channel Verification Connections
3. Reinstall the top cover on the NI CAL-9212.
4. Connect the NI CAL-9212 to the NI 9212, as shown in Figure 2.
5. On the Fluke 5522A calibrator, lock the voltage range to 3.3 V to reduce loading error.
a. Set the output voltage to 2.0 V.
b. Press the 3.3 V auto button to lock the 3.3 V range.
6. Set the calibrator output to a Test Point value indicated in Table 4.
7. Set the calibrator to Operate mode (OPR).
8. Acquire and average samples.
a. Create and configure an AI voltage channel on the NI 9212 according to Table 2.
Table 2. NI 9212 Voltage Channel Configuration
Physical Channels
Input Range (mV) Scaled
Units
Terminal
Configuration
Min Max
cDAQ1Mod8/ai0:7 -78.125 78.125 Vo l t s Differential
Calibrator NI CAL-9212
TC –
LO
GROUND LUG
TC +
HI

NI 9212 Calibration Procedure |© National Instruments |7
b. Configure the AI voltage channel timing according to Table 3.
c. Start the task.
d. Average the readings.
e. Clear the task.
9. Set the calibrator to Standby mode (STBY).
10. Compare the average to the limits in Table 4.
11. Repeat steps 6 through 10 for each test point.
12. Repeat steps 6 through 11 for each ADC timing mode on the NI 9212.
Note The test limits listed in Table 4 are derived using the values in Table 11.
Table 3. NI 9212 Voltage Channel Timing Configuration
ADC Timing Mode
Sample
Mode
Samples to
Read Rate (S/s) Timeout (s)
High Resolution Finite 20 1.8 30
Best 50 Hz Rejection 80 7.1
Best 60 Hz Rejection 100 8.3
High Speed 1,000 95
Table 4. NI 9212 Voltage Verification Test Limits for Positive and Negative Test Points
ADC
Timing
Mode
Range (mV) Test Point 1-Year Limits
Min Max Location
Value
(mV)
Lower
Limit (mV)
Upper
Limit (mV)
High
Resolution,
Best
50/60 Hz
Rejection
-78.125 78.125 Negative FS -70 -70.020 -69.980
Negative Mid -35 -35.013 -34.987
Positive Mid 35 34.987 35.013
Positive FS 70 69.980 70.020
High Speed Negative FS -70 -70.022 -69.978
Negative Mid -35 -35.014 -34.986
Positive Mid 35 34.986 35.014
Positive FS 70 69.978 70.022

8|ni.com |NI 9212 Calibration Procedure
13. Loosen the captive screws and remove the top cover from the NI CAL-9212.
14. Disconnect the calibrator from the NI CAL-9212.
15. Short the TC+ and TC- terminals on the NI CAL-9212 together.
16. Reinstall the top cover on the NI CAL-9212.
17. Acquire and average samples.
a. Create and configure an AI voltage channel on the NI 9212 according to Table 2.
b. Configure the AI voltage channel timing according to Table 3.
c. Start the task.
d. Average the readings.
e. Clear the task.
18. Compare the average to the limits in Table 5.
Note The test limits listed in Table 5 are derived using the values in Table 11.
19. Repeat steps 17 through 18 for each ADC timing mode on the NI 9212.
20. Remove the NI CAL-9212 from the NI 9212.
21. Loosen the captive screws and remove the top cover from the NI CAL-9212.
22. Disconnect the short from the NI CAL-9212.
CJC Verification
Complete the following procedure to determine the As-Found status of the NI 9212.
1. Loosen the captive screws and remove the top cover from the NI CAL-9212.
2. Connect the calibrator to the NI CAL-9212, as shown in Figure 4.
Table 5. NI 9212 Voltage Verification Test Limits for Zero Test Points
ADC Timing
Mode
Range (mV) Test Point 1-Year Limits
Min Max Location
Value
(mV)
Lower
Limit (mV)
Upper
Limit (mV)
High
Resolution
-78.125 78.125 Zero 0-0.0051 0.0051
Best 50/60 Hz
Rejection
-0.0052 0.0052
High Speed -0.0056 0.0056

NI 9212 Calibration Procedure |© National Instruments |9
Figure 4. CJC Channel Verification Connections
3. Reinstall the top cover on the NI CAL-9212.
4. Connect the NI CAL-9212 to the NI 9212, as shown in Figure 2.
5. Set the calibrator to 2-Wire Compensation mode.
6. Set the calibrator output to a Test Point value indicated in Table 8.
7. Set the calibrator to Operate mode (OPR).
8. Wait at least 15 seconds for the NI 9212 to settle before proceeding to the next step.
9. Acquire and average samples.
a. Create and configure an AI voltage channel on the NI 9212 according to Table 6.
b. Configure the AI voltage channel timing according to Table 7.
Table 6. NI 9212 CJC Channel Configuration
Physical Channels
Input Range (V) Scaled
Units
Terminal
Configuration
Min Max
cDAQ1Mod8/_cjtempx-2.5 2.5 Vo l t s RSE
Table 7. NI 9212 CJC Channel Timing Configuration
ADC Timing Mode
Sample
Mode
Samples to
Read Rate (S/s) Timeout (s)
High Resolution Finite 20 1.8 30
Best 50 Hz Rejection 80 7.1
Best 60 Hz Rejection 100 8.3
High Speed 1,000 95
Calibrator
LO
HI SENSE
LO SENSE
HI
NI CAL-9212
CJC
x Input –
CJC x SENSE +
CJC x SENSE –
GROUND LUG
CJCxInput +

10 |ni.com |NI 9212 Calibration Procedure
c. Start the task.
d. Average the readings.
e. Clear the task.
10. Perform the following calculation to scale the voltage average to resistance.
11. Compare the calculated resistance to the limits in Table 8.
12. Repeat steps 9 through 11 for each ADC timing mode on the NI 9212.
13. Repeat steps 6 through 12 for each test point.
14. Set the calibrator to Standby mode (STBY).
15. Remove the NI CAL-9212 from the NI 9212.
16. Loosen the captive screws and remove the top cover from the NI CAL-9212.
17. Disconnect the calibrator from the NI CAL-9212.
18. Repeat steps 2 through 17 for the other CJC channel on the NI 9212.
Note The test limits in Table 8 are derived using the values in Tables 6 and 12.
Table 8. NI 9212 CJC Verification Test Limits
ADC
Timing
Mode
Test Point 1-Year Limits
Location Value (Ω)Lower Limit (Ω)Upper Limit (Ω)
High
Resolution
Offset 1,000 998.31 1,001.69
Gain 1 19,000 18,983.26 19,016.74
Gain 2 100,000 99,870.09 100,129.91
Best
50/60 Hz
Rejection
Offset 1,000 998.2 1,001.8
Gain 1 19,000 18,982.76 19,017.24
Gain 2 100,000 99,864.75 100,135.25
High Speed Offset 1,000 997.37 1,002.63
Gain 1 19,000 18,908.53 19,091.47
Gain 2 100,000 99,125.27 100,874.73
Resistance 28000 Voltage
2.5 Voltage–
-------------------------------------=