background image

NI USB-443x Calibration Procedure

2

ni.com

Software Requirements

Calibrating the NI USB-443

x

 device

 

requires installing NI-DAQmx 9.3 or later on the calibration 

system. You can download the NI-DAQmx driver from 

ni.com/downloads

. NI-DAQmx supports 

conducting a calibration in several programming language application development environments 
(ADEs). When you install NI-DAQmx, you only need to install support for the ADE that you intend 
to use.

Documentation Requirements

For information about NI-DAQmx and the NI USB-443

x

, you can consult the following documents:

DAQ Getting Started 

guides—provides instructions for installing and configuring NI USB-443

x

 

devices.

NI-DAQmx C Reference Help

—contains the C reference and general information about 

measurement concepts.

NI USB-443x Specifications

—provides the published specification values for the NI USB-443

x

Refer to the most recent 

NI USB-443x Specifications

 online at 

ni.com/manuals

.

NI-DAQmx Help

—includes information about creating applications that use NI-DAQmx.

These documents are installed with NI-DAQmx. You can also download the latest versions from the 
NI Web site at 

ni.com/manuals

.

Calibration Interval

National Instruments recommends a calibration interval of one year

 

for the NI USB-443

x

. Adjust the 

recommended calibration interval based on the measurement accuracy demands of your application.

Summary of Contents for USB-443 Series

Page 1: ...tion Procedures 4 Initial Setup 4 Changing Coupling on NI USB 443x Devices 5 Verification 6 Analog Input Performance Verification 6 AI Offset Verification 6 AI AC Coupled Gain Accuracy Verification 7...

Page 2: ...ed guides provides instructions for installing and configuring NI USB 443x devices NI DAQmx C Reference Help contains the C reference and general information about measurement concepts NI USB 443x Spe...

Page 3: ...Function Generator HP Agilent 33250A Timebase Frequency Accuracy Frequency Range up to 10 kHz Frequency Accuracy 5 ppm Voltage Range up to 9 Vpk Digital Multimeter NI 4071 AO Gain AO Offset DC Voltag...

Page 4: ...e device and configure it in Measurement Automation Explorer MAX 2 Verification Verify the existing operation of the device This step confirms whether the device is operating within the published spec...

Page 5: ...re is no 30 seconds wait between setting the coupling on the device and starting the acquisition For flexibility NI DAQmx gives you the ability to download channel configuration settings to hardware a...

Page 6: ...f NI USB 443x devices Refer to the NI USB 443x Specifications for the number of channels and performance specifications AI Offset Verification Note Skip the AC coupled portion of this procedure if bot...

Page 7: ...lication 7 Repeat steps 1 through 6 In step 2 set the coupling parameter to AC Note Skip the AC coupled portion of this procedure if both of the following apply Your device is hardware revision C or e...

Page 8: ...ifying only the channels used in your application AI DC Coupled Gain Accuracy Verification Complete the following steps to verify DC coupled gain accuracy 1 Connect the output of the calibrator to the...

Page 9: ...1 through 5 In step 2 output 9 VDC instead of 9 VDC Subtract the averaged value measured for 0 VDC from the 9 VDC measurement Table 7 AI DC Coupled Gain Accuracy Verification Configuration for NI USB...

Page 10: ...fy the AO offset 1 Connect channel AO 0 on the device to the input of the multimeter 2 Create and configure an AO voltage task on the NI USB 4431 as shown in Table 10 3 Create an array of length 96 00...

Page 11: ...nfigured to generate samples continuously 5 Wait 100 ms This compensates for the filter delay of the analog output channel 6 Measure the DC voltage of the analog output channel using the multimeter in...

Page 12: ...evice 2 Configure the function generator to generate a 10 kHz sine wave with an amplitude of 9 Vpk and no DC offset 3 Create and configure an AI voltage task on the NI USB 443x as shown in Table 14 4...

Page 13: ...t the output of the calibrator to all input channels on the device Use the BNC T connectors to route the signal to all of the inputs 2 Configure the calibrator to output a 1 kHz signal with a 6 3 Vrms...

Page 14: ...for NI USB 443x Configuration Value Minimum value 10 0 Maximum value 10 0 Terminal configuration Pseudodifferential Acquisition mode Continuous Rate 1000 0 Coupling AC Physical channel Dev_name aix D...

Page 15: ...cel if there has been any error during the AI calibration or if you do not want to save the new AI calibration constants in the device EEPROM Use the action commit to save the new AI calibration const...

Page 16: ...tinuously 6 Wait 100 ms This compensates for the filter delay of the analog output channel 7 Measure the DC voltage of channel AO 0 on the device using the multimeter Record this value as actualHighVo...

Page 17: ...device EEPROM The analog output of the device is now calibrated with respect to your external equipment After calibrating the device verify the analog output operation by repeating the Analog Output P...

Page 18: ...rt export data 2011 National Instruments Corporation All rights reserved 373489A 01 Oct11 Where to Go for Support The National Instruments Web site is your complete resource for technical support At n...

Reviews: