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NI 9421

8-Channel 24 V Logic, 100 µs, Sinking Digital Input Module

  • 8-channel, 100 us digital input
  • Hot-swappable operation
  • -40 to 70 °C operating range
  • 12 to 24 V logic, sinking digital inputs
  • Extreme industrial certifications/ratings
  • D-Sub or screw-terminal connector options

The National Instruments NI 9421 is an 8-channel, 100 µs sinking digital input module for any NI CompactDAQ or CompactRIO chassis. Each channel is compatible with 12 to 24 V signals and features transient overvoltage protection of 2,300 Vrms between the input channels and earth ground. Each channel also has an LED that indicates the state of that channel. The NI cRIO-9421 works with industrial logic levels and signals for direct connection to a wide array of industrial switches, transducers, and devices.

There are two connector options for the NI 9421 - a 10-position screw-terminal connector and a 25-position D-Sub connector. This industry-standard 25-position D-Sub connector provides for low-cost cabling to a wide variety of accessories available from NI or other vendors. A number of vendors with custom D-Sub cable fabrication services can deliver cables with a pinout that matches your exact application needs.

NI recommends the NI 9932 strain-relief connector accessory for the NI 9421 for screw-terminal connectivity and the NI 9934 accessory for 25-position D-Sub connectivity.

View Diagram

Select one of the following options for product configuration and pricing:

Select Module and Accessories Below » Configure and Price a Complete CompactDAQ/CompactRIO System »
 
Module Accessories   Chassis, Controllers, Modules Software & Services
Step 1: Verify Device and Quantity Selection
Part
Number
Description Est Ship Days Glossary Definition US Dollars
(change)
Qty
  NI 9421      
779002-01 Screw Terminal
NI Recommended
1 - 2 $ 99
779136-01 D-Sub Connector 5 - 10 $ 99
Step 2: Select Optional Accessories
Part
Number
Description Est Ship Days Glossary Definition US Dollars
(change)
Qty
Screw Terminals
779017-01 NI 9932 Backshell with 10-pos connector block (qty 1) 1 - 2 $ 29
779105-01 NI 9936 10-pos screw term connector block (qty 10) 1 - 2 $ 49
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
1 - 2 $ 109
Step 3: Select Optional Accessories
Part
Number
Description Est Ship Days Glossary Definition US Dollars
(change)
Qty
Connectivity Accessories
781081-01 25-pin DSUB to Screw Terminal Block, DIN Rail Mount 5 - 10 $ 59
Step 4: Add to Cart or Get a Quote

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You have selected United States as the country where you will use the product(s) (change).

Specifications Documents


Specifications Summary

General
Product Name NI 9421
Product Family Industrial I/O
Form Factor CompactDAQ , CompactRIO
Operating System/Target Windows , Real-Time
Measurement Type Digital
Isolation Type Ch-Earth Ground Isolation
RoHS Compliant Yes
Product Name NI 9421 D-Sub
Product Family Industrial I/O
Form Factor CompactDAQ , CompactRIO
Operating System/Target Windows , Real-Time
Measurement Type Digital
Isolation Type Ch-Earth Ground Isolation
RoHS Compliant Yes
Analog Input
Channels 0 , 0
Single-Ended Channels 0
Differential Channels 0
Channels 0 , 0
Single-Ended Channels 0
Differential Channels 0
Analog Output
Channels 0
Channels 0
Digital I/O
Bidirectional Channels 0
Input-Only Cannels 8
Output-Only Channels 0
Number of Channels 0 , 8 , 0
Timing Hardware
Max Clock Rate 10 KHz
Logic Levels 24 V
Input Current Flow Sinking
Supports Handshaking I/O? Yes
Supports Pattern I/O? Yes
Maximum Input Range 24.0 , 0.0 V
Bidirectional Channels 0
Input-Only Cannels 8
Output-Only Channels 0
Number of Channels 0 , 8 , 0
Timing Hardware
Max Clock Rate 10 KHz
Logic Levels 5 V , Other
Input Current Flow Sinking
Supports Handshaking I/O? Yes
Supports Pattern I/O? Yes
Maximum Input Range 24.0 , 0.0 V
Counter/Timers
Counters 0
Counters 0
Physical Specifications
Length 9.0 cm
Width 2.300 cm
I/O Connector Screw terminals
Minimum Operating Temperature -40.0 °C
Maximum Operating Temperature 70.0 °C
Minimum Storage Temperature -40.0 °C
Maximum Storage Temperature 85.0 °C
Length 9.0 cm
Width 2.300 cm
I/O Connector 25-pin D-Sub
Minimum Operating Temperature -40.0 °C
Maximum Operating Temperature 70.0 °C
Minimum Storage Temperature -40.0 °C
Maximum Storage Temperature 85.0 °C

System Assurance Programs

Reduce your setup time and total cost of ownership, and get a system you can use out of the box with National Instruments system assurance programs. System assurance programs include:

  • Installation and integration test of all individual hardware
  • Courtesy installation of system driver sets and application development environments
  • Extended warranty and calibration coverage for up to five years
  • Custom documentation plus a custom restore and startup utility

This service is only available for PXI, NI CompactRIO, and NI Compact FieldPoint systems.

Extended Warranties

National Instruments designs and manufactures all products to minimize failures, however 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. In addition, they offer the following benefits:

  • 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 restore the hardware to manufacturing specifications

For more information about your warranty options:

Calibration

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Training

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Repair Services

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 restore the hardware to manufacturing specifications.

Technical Support

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