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NI USB-9421

Portable USB-Based High-Voltage Digital Input

  • Plug-and-play connectivity via USB
  • Screw terminal or D-Sub connector options
  • 8 sinking digital input channels with 24 V logic levels
  • NI-DAQmx driver software to simplify configuration and measurements
  • Small, portable module (12.1 by 8.6 by 2.5 cm)
  • 250 Vrms channel-to-earth ground isolation
  • Data Sheet

Step 1: Verify Device and Quantity Selection
Part
Number
Description Est Ship Days Glossary Definition US Dollars
(change)
Qty
  NI USB-9421      
779451-01 Screw Terminal
NI Recommended
-- For price, select country  
779452-01 D-Sub Connector -- For price, select country  
Step 2: Select Optional Accessories
Part
Number
Description Est Ship Days Glossary Definition US Dollars
(change)
Qty
Other
777550-01 USB/PCMCIA Strain Relief Kit for laptops -- For price, select country  
779489-01 DAQ 7 Steps Tutorial -- For price, select country  
Step 3: Add to Cart or Get a Quote
Step 2: Select Connectivity Accessory
Part
Number
Description Est Ship Days Glossary Definition US Dollars
(change)
Qty
Screw Terminals
779104-01 NI 9934 25pin D-Sub connector kit
NI Recommended
-- For price, select country  
Step 3: Select Optional Accessories
Part
Number
Description Est Ship Days Glossary Definition US Dollars
(change)
Qty
Other
777550-01 USB/PCMCIA Strain Relief Kit for laptops -- For price, select country  
779489-01 DAQ 7 Steps Tutorial -- For price, select country  
Step 4: Add to Cart or Get a Quote

Please select the country where you will use the product(s) so that we can provide you with accurate pricing, availability, and purchasing information

The National Instruments USB-9421 is a data acquisition module with integrated signal conditioning that provides plug-and-play connectivity via USB for faster setup and measurements. This module has eight sinking digital input channels, specifically designed for industrial and control applications. Each input channel accepts high-voltage levels between 11 and 30 V for direct connection to 12 and 24 V systems. With both screw terminal and D-Sub connector options, the NI USB-9421 is ideal for flexible, low-cost signal wiring. In addition, this module includes channel-to-earth ground isolation for safety, noise immunity and high common-mode voltage range.

This USB data acquisition module is compatible with only Microsoft Windows OSs using NI-DAQmx driver software. Browse the information in the Resources tab to learn more about NI-DAQmx or download the driver. This USB data acquisition module is not compatible with the Traditional NI-DAQ (Legacy) driver.

For applications that require a higher channel count, consider NI SCXI signal conditioning hardware.

Specifications Documents


Specifications Summary


Extended Warranties

National Instruments designs and manufactures all products to minimize failures, but we know unexpected failures can still occur. Extended warranties provide a fixed economical price at the time of system purchase covering any repair costs for up to three years.

  • Significant cost savings compared to individual repair incidents
  • Fault location, diagnostics, and repair by NI any time the system product fails
  • All parts and labor costs covered as well as any adjustments needed to bring the hardware back to manufacturing specifications

Calibration

NI recognizes the need to maintain properly calibrated devices for high-accuracy measurements. We provide manual calibration procedures, services to recalibrate your products, and automated calibration software to calibrate many of our measurement products.

Training

NI training is the fastest, most certain route to productivity with NI tools and successful application development.

Repair Services

  • You can return your registered product under warranty at no additional labor and parts cost. NI offers fault location, diagnostics, and repair any time the system fails as well as any adjustments needed to bring the hardware back to manufacturing specifications.
  • Contact us to obtain a Return Material Authorization (RMA) form and shipping instructions
  • View your RMA support request status online
  • Register your product

Technical Support

www.ni.com/support

Select your application need to see compatible software options for the NI USB-9421 .

Application Need

Graphical Programming Text-Based Programming
Select any of the following software products
Part
Number
Description Est Ship Days Glossary Definition US Dollars
(change)
Qty
776670-09 NI LabVIEW Full Development System for Windows (English)
NI Recommended
-- For price, select country  
777756-09 NI LabVIEW Full Development System for Linux -- For price, select country  
776675-01 LabVIEW Application Builder for Windows (English)
NI Recommended
-- For price, select country  
777755-03 NI LabVIEW Application Builder for Linux -- For price, select country  
778406-03 NI LabVIEW Report Generation Toolkit for Microsoft Office -- For price, select country  
778807-09 DIAdem Advanced Edition (English) -- For price, select country  

Please select the country where you will use the product(s) so that we can provide you with accurate pricing, availability, and purchasing information

Select any of the following software products
Part
Number
Description Est Ship Days Glossary Definition US Dollars
(change)
Qty
776800-09 LabWindows/CVI Full Development System for Windows -- For price, select country  
778801-09 NI Measurement Studio Professional Edition for Microsoft Visual Studio -- For price, select country  
779384-03 NI LabWindows/CVI Run-Time Module for Linux -- For price, select country  
777875-03 NI LabWindows/CVI Enterprise Connectivity Toolkit for Windows -- For price, select country  
778807-09 DIAdem Advanced Edition (English) -- For price, select country  

Please select the country where you will use the product(s) so that we can provide you with accurate pricing, availability, and purchasing information

Other compatible software: ANSI C/C++, C#, Visual Basic .NET, Visual Basic 6.0
Graphical Programming Text-Based Programming
Option 1: Select one of the following NI Developer Suite packages or Configure Your NI Developer Suite >>
Part
Number
Description Est Ship Days Glossary Definition US Dollars
(change)
Qty
DS410841 NI Developer Suite Core with Automated Test Option (English) -- For price, select country  

Please select the country where you will use the product(s) so that we can provide you with accurate pricing, availability, and purchasing information

Option 2: Select any of the following software products
Part
Number
Description Est Ship Days Glossary Definition US Dollars
(change)
Qty
776670-09 NI LabVIEW Full Development System for Windows (English)
NI Recommended
-- For price, select country  
777756-09 NI LabVIEW Full Development System for Linux -- For price, select country  
776675-01 LabVIEW Application Builder for Windows (English)
NI Recommended
-- For price, select country  
777755-03 NI LabVIEW Application Builder for Linux -- For price, select country  
777777-09 NI TestStand Development System for Windows -- For price, select country  

Please select the country where you will use the product(s) so that we can provide you with accurate pricing, availability, and purchasing information

Option 1: Select one of the following NI Developer Suite packages or Configure Your NI Developer Suite >>
Part
Number
Description Est Ship Days Glossary Definition US Dollars
(change)
Qty
DS410841 NI Developer Suite Core with Automated Test Option (English) -- For price, select country  

Please select the country where you will use the product(s) so that we can provide you with accurate pricing, availability, and purchasing information

Option 2: Select any of the following software products
Part
Number
Description Est Ship Days Glossary Definition US Dollars
(change)
Qty
776800-09 LabWindows/CVI Full Development System for Windows -- For price, select country  
778801-09 NI Measurement Studio Professional Edition for Microsoft Visual Studio -- For price, select country  
779384-03 NI LabWindows/CVI Run-Time Module for Linux -- For price, select country  
777875-03 NI LabWindows/CVI Enterprise Connectivity Toolkit for Windows -- For price, select country  
777777-09 NI TestStand Development System for Windows -- For price, select country  

Please select the country where you will use the product(s) so that we can provide you with accurate pricing, availability, and purchasing information

Other compatible software: ANSI C/C++, C#, Visual Basic .NET, Visual Basic 6.0
Graphical Programming Text-Based Programming
Option 1: Select one of the following NI Developer Suite packages or Configure Your NI Developer Suite >>
Part
Number
Description Est Ship Days Glossary Definition US Dollars
(change)
Qty
DS410863 NI Developer Suite Core with Control Design and Simulation Option (English) -- For price, select country  

Please select the country where you will use the product(s) so that we can provide you with accurate pricing, availability, and purchasing information

Option 2: Select any of the following software products
Part
Number
Description Est Ship Days Glossary Definition US Dollars
(change)
Qty
776670-09 NI LabVIEW Full Development System for Windows (English)
NI Recommended
-- For price, select country  
777756-09 NI LabVIEW Full Development System for Linux -- For price, select country  
780050-09 NI LabVIEW Control Design and Simulation Module -- For price, select country  
778941-03 NI LabVIEW System Identification Toolkit for Windows -- For price, select country  
778552-03 NI LabVIEW Simulation Interface Toolkit for Windows -- For price, select country  

Please select the country where you will use the product(s) so that we can provide you with accurate pricing, availability, and purchasing information

Select any of the following software products
Part
Number
Description Est Ship Days Glossary Definition US Dollars
(change)
Qty
776800-09 LabWindows/CVI Full Development System for Windows -- For price, select country  
778801-09 NI Measurement Studio Professional Edition for Microsoft Visual Studio -- For price, select country  
779667-09 NI LabWindows/CVI Real-Time Module -- For price, select country  
778915-03 NI LabWindows/CVI Execution Trace Toolkit -- For price, select country  
779509-03 NI LabWindows/CVI PID Control Toolkit -- For price, select country  
777757-01 NI PID Toolkit for Visual Basic -- For price, select country  

Please select the country where you will use the product(s) so that we can provide you with accurate pricing, availability, and purchasing information

Other compatible software: ANSI C/C++, C#, Visual Basic .NET, Visual Basic 6.0
Graphical Programming Text-Based Programming
Option 1: Select one of the following NI Developer Suite packages or Configure Your NI Developer Suite >>
Part
Number
Description Est Ship Days Glossary Definition US Dollars
(change)
Qty
DS410838 NI Developer Suite Core with Real-Time Deployment Option (English) -- For price, select country  

Please select the country where you will use the product(s) so that we can provide you with accurate pricing, availability, and purchasing information

Option 2: Select any of the following software products
Part
Number
Description Est Ship Days Glossary Definition US Dollars
(change)
Qty
776670-09 NI LabVIEW Full Development System for Windows (English)
NI Recommended
-- For price, select country  
777756-09 NI LabVIEW Full Development System for Linux -- For price, select country  
777844Y-09 NI LabVIEW Real-Time Module for Windows -- For price, select country  
778915-03 NI LabVIEW Execution Trace Toolkit -- For price,