National Instruments NI 9226 Manual

NI-9226

CALIBRATION PROCEDURE
NI 9216/9226
8-Channel, 400 S/s Aggregate, 0 Ωto 400 Ω/4000 Ω,
PT100 RTD/PT1000 RTD C Series Temperature Input Module
This document contains the verification and adjustment procedures for the NI 9216 and NI 9226.
In this document, the NI 9216 and NI 9226 are inclusively referred to as NI 9216/9226. For more
information about calibration solutions, visit ni.com/calibration.
Contents
Software.................................................................................................................................... 1
Documentation.......................................................................................................................... 2
Test Equipment......................................................................................................................... 3
Test Conditions......................................................................................................................... 3
Initial Setup............................................................................................................................... 3
Verification ............................................................................................................................... 4
Accuracy Verification....................................................................................................... 4
Adjustments .............................................................................................................................. 6
Accuracy Adjustment ....................................................................................................... 6
EEPROM Update ..................................................................................................................... 7
Reverification ........................................................................................................................... 7
Accuracy Under Calibration Conditions .................................................................................. 7
Worldwide Support and Services ............................................................................................. 8
Software
Calibrating the NI 9216/9226 requires the installation of NI-DAQmx 14.5 or later on the
calibration system. You can download NI-DAQmx from ni.com/downloads. NI-DAQmx
supports LabVIEW, LabWindows™/CVI™, ANSI C, Microsoft Visual C++, Microsoft Visual
Basic .NET, and Microsoft Visual C#. When you install NI-DAQmx you only need to install
support for the application software that you intend to use.

2|ni.com |NI 9216/9226 Calibration Procedure
Documentation
Consult the following documents for information about the NI 9216/9226, 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 Guide
NI-DAQmx installation and hardware setup
NI 9216 Getting Started Guide
NI 9216 connection information
NI 9216 Datasheet
NI 9216 circuitry and specifications
NI 9226 Getting Started Guide
NI 9226 connection information
NI 9226 Datasheet
NI 9226 circuitry and specifications
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 9216/9226 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.
Test Conditions
The following setup and environmental conditions are required to ensure the NI 9216/9226
meets published specifications.
• Keep connections to the device 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 device are secure.
• Use shielded copper wire for all cable connections to the device. Use twisted-pairs wire to
eliminate noise and thermal offsets.
• Maintain an ambient temperature of 20 °C to 28 °C.
• Keep relative humidity below 80%.
• Allow a warm-up time of at least 10 minutes to ensure that the NI 9216/9226 measurement
circuitry is at a stable operating temperature.
Initial Setup
Complete the following steps to set up the NI 9216/9226.
1. Install NI-DAQmx.
2. Make sure the cDAQ-9178 power source is not connected to the chassis.
3. Connect the cDAQ-9178 chassis 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 cDAQ-9178 chassis
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 cDAQ-9178 chassis. Leave slots 1 through 7 of the
cDAQ-9178 chassis empty.
5. Connect the cDAQ-9178 chassis to your host computer.
Table 1. Recommended Equipment
Equipment
Recommended
Models Requirements
Calibrator Fluke 5522A Use a high-precision resistance source with gain
accuracy ≤40 ppm and offset error ≤2 mΩ for the
NI 9216 and offset error ≤20 mΩ for the NI 9226.
Chassis cDAQ-9178 —

4|ni.com |NI 9216/9226 Calibration Procedure
6. Connect the power source to the 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.
Verification
The following performance verification procedure describes the sequence of operation and test
points required to verify the NI 9216/9226. The verification procedure assumes that adequate
traceable uncertainties are available for the calibration references.
Accuracy Verification
Complete the following procedure to determine the As-Found status of the NI 9216/9226.
1. Set the calibrator to Standby mode (STBY).
2. Connect the desired channel of the NI 9216/9226 to the calibrator as shown in Figure 1.
Connect only one channel at a time.
Figure 1. 4-Wire Resistance Connections
3. Set the calibrator as a resistance source to a Test Point value indicated in Table 2.
4. Set calibrator COMP to 4-wire.
Table 2. NI 9216/9226 Accuracy Verification Test Limits
Module
Range Test Point 1-Year Limits
Minimum
(Ω)
Maximum
(Ω)Value (Ω)
Upper
Limit (Ω)
Lower
Limit (Ω)
NI 9216 0 400
00.03 -0.03
100 100.042 99.958
320 320.0684 319.9316
NI 9226 0 4000
00.3 -0.3
1000 1000.43 999.57
3200 3200.72 3199.28
EX+
HI
LO
AUX LO
AUX HI
EX–
RTD–
RTD+
NI 9216/9226
CALIBRATOR 4-Wire Connection

NI 9216/9226 Calibration Procedure |© National Instruments |5
Note The limits are only based on the NI 9216/9226 accuracy. The uncertainty of
calibration standard is not included.
Note The test limits listed in Table 2 are derived using the values in Table 6.
5. Set the calibrator to Operate mode (OPR).
6. Acquire and average samples from one channel.
a. Create and configure a 4-wire AI resistance task on the NI 9216/9226 according to
Table 3.
b. Configure the ADC Timing Mode to High Resolution.
Note Use appropriate channel number in place of “x” in “AIx.” For example, use
AI3 for channel 3.
c. Configure the task timing according to Table 4.
d. Start the task.
e. Read the samples from the NI 9216/9226.
f. Average the samples.
g. Stop and clear the task.
7. Compare the per-channel averages to the limits in Table 2.
8. Set the calibrator to Standby mode (STBY).
9. Repeat steps 3 through 8 for each test point listed in Table 2.
10. Disconnect the NI 9216/9226 channel from the calibrator.
11. Repeat steps 2 through 10 for any other desired channel of NI 9216/9226.
Table 3. NI 9216/9226 Voltage Configuration
Module Physical Channel
Range
Minimum (Ω)Maximum (Ω)
NI 9216 AIx 0 400
NI 9226 AIx 0 4000
Table 4. NI 9216/9226 Task Timing Configuration
Sample Mode Samples Per Channel Rate (S/s)
Finite Samples 10 5

6|ni.com |NI 9216/9226 Calibration Procedure
Adjustments
The following performance adjustment procedure describes the sequence of operation required
to adjust the NI 9216/9226.
Accuracy Adjustment
Complete the following procedure to adjust the accuracy performance of the NI 9216/9226.
1. Set the calibrator to Standby mode (STBY).
2. Connect the desired channel of the NI 9216/9226 to the calibrator as shown in Figure 1.
Connect only one channel at a time.
3. Adjust the desired channel of the NI 9216/9226.
a. Initialize a calibration session on the NI 9216/9226. The default password is NI.
b. Input the external temperature in degrees Celsius.
c. Call the DAQmx Get NI 9216/9226 Calibration Adjustment Points function to obtain
an array of recommended calibration resistance values.
d. Set the calibrator to a reference value determined by the array of recommended
calibration voltages.
e. Set calibrator COMP to 4-wire.
f. Set the calibrator to Operate mode (OPR).
g. Call and configure the NI 9216/9226 adjustment function according to Table 5.
Note Use appropriate channel number in place of “x” in “AIx.” For example, use
AI3 for channel 3.
Note The module acquisition is started each time the adjust function is called.
h. Set the calibrator to Standby mode (STBY).
i. Repeat steps d through h for each point in the array.
j. Close the calibration session with action commit.
4. Disconnect the NI 9216/9226 channel from the calibrator.
5. Repeat steps 2 through 4 to calibrate any other desired channel of NI 9216/9226.
Table 5. Gain Adjustment Configuration
Physical Channel Reference Value
AIx The reference resistance value from the array
of adjustment points

NI 9216/9226 Calibration Procedure |© National Instruments |7
EEPROM Update
When an adjustment procedure is completed, the NI 9216/9226 internal calibration memory
(EEPROM) is immediately updated.
If you do not want to perform an adjustment, you can update the calibration date and onboard
calibration temperature without making any adjustments by initializing an external calibration,
setting the C Series calibration temperature, and closing the external calibration.
Reverification
Repeat the Verification section to determine the As-Left status of the device.
Note If any test fails Reverification after performing an adjustment, verify that you
have met the Test Conditions before returning your device to NI. Refer to Worldwide
Support and Services for assistance in returning the device to NI.
Accuracy Under Calibration Conditions
The values in the following table are based on calibrated scaling coefficients, which are stored
in the onboard EEPROM.
The following accuracy table is valid for calibration under the following conditions:
• Ambient temperature 20 °C to 28 °C
• NI 9216/9226 installed in slot 8 of an cDAQ-9178 chassis
• Slots 1 through 7 of the cDAQ-9178 chassis are empty
Note For operational specifications, refer to the most recent NI 9216 Datasheet or
NI 9226 Datasheet online at ni.com/manuals.
Table 6. NI 9216/9226 Accuracy Under Calibration Conditions
Module Gain Error Offset Error
NI 9216 ±0.012% ±0.03 Ω
NI 9226 ±0.013% ±0.3 Ω

©2015–2018 National Instruments. All rights reserved.
375425C-01 Oct18
Refer to the NI Trademarks and Logo Guidelines at ni.com/trademarks for more information on National Instruments trademarks. Other
product and company names mentioned herein are trademarks or trade names of their respective companies. For patents covering National
Instruments products/technology, refer to the appropriate location: Help»Patents in your software, the patents.txt file on your media, or the
National Instruments Patents Notice at ni.com/patents. You can find information about end-user license agreements (EULAs) and third-party
legal notices in the readme file for your NI product. Refer to the Export Compliance Information at ni.com/legal/export-compliance
for the National Instruments global trade compliance policy and how to obtain relevant HTS codes, ECCNs, and other import/export data. NI MAKES
NO EXPRESS OR IMPLIED WARRANTIES AS TO THE ACCURACY OF THE INFORMATION CONTAINED HEREIN AND SHALL NOT BE LIABLE FOR
ANY ERRORS. U.S. Government Customers: The data contained in this manual was developed at private expense and is subject to the applicable
limited rights and restricted data rights as set forth in FAR 52.227-14, DFAR 252.227-7014, and DFAR 252.227-7015.
Worldwide Support and Services
The NI website is your complete resource for technical support. At ni.com/
support you have access to everything from troubleshooting and application development
self-help resources to email and phone assistance from NI Application Engineers.
Visit ni.com/services for NI Factory Installation Services, repairs, extended warranty, and
other services.
Visit ni.com/register to register your NI product. Product registration facilitates technical
support and ensures that you receive important information updates from NI.
NI corporate headquarters is located at 11500 North Mopac Expressway, Austin, Texas,
78759-3504. NI also has offices located around the world. For telephone support in the United
States, create your service request at ni.com/support or dial 1 866 ASK MYNI (275 6964).
For telephone support outside the United States, visit the Worldwide Offices section of
ni.com/niglobal to access the branch office websites, which provide up-to-date contact
information, support phone numbers, email addresses, and current events.