National Instruments NI 9421 Digital Input Module

National Instruments NI 9421 Digital Input Module

This National Instruments NI 9421 Digital Input Module for CompactRIO ships in the NI static bag. It has the 10-position screw terminal connector. This is also known as the cRIO-9421.

Part Number: 779002-01

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Stock # 72029-5
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National Instruments NI 9421 Digital Input Module

  • 8-Channel, 100 µs Digital Input
  • Hot-Swappable Operation
  • Extreme Industrial Certifications and Ratings
  • Spring Terminal or D-SUB Front Connection
  • Optional Conformal Coating (D-SUB Model)


The National Instruments 9421 Digital Input Module is an eight-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 level 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 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. This product is also known as the NI-cRIO-9421.

Product Family: cRIO-9421, cRio 9421, cRIO9421, 9421

Important Notice: Please note that any additional items included with this equipment such as accessories, manuals, cables, calibration data, software, etc. are specifically listed in the above stock item description and/or displayed in the photos of the equipment. Please contact one of our Customer Support Specialists if you have any questions about what is included with this equipment or if you require any additional information.

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