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Industrial productPart number: NI 9421

NI 9421 Digital Input Module 8-Channel 24V C Series

Product lifecycleConfirm with quotationAvailabilityIn stock

Part number: NI 9421
Availability: In stock
Category: PLC & I/O Systems
Subcategory: Digital I/O Modules

✓ Part-number review✓ Condition stated in quote✓ Worldwide delivery options

Product overview

NI 9421 product information

NI NI 9421

Rugged 8-channel 24V sourcing digital input C Series module for reliable industrial signal acquisition in NI CompactDAQ and CompactRIO systems

Brand	NI
Model	NI 9421
Voltage	24V DC
Country of Origin	Hungary
Weight	150 g
Dimensions	90 x 70 x 23 mm
Warranty	6 months
Certifications	CE, UL, RoHS
SKU / MPN	781238-01
What’s in the box	NI 9421 module, 20-pin DSUB front connector, user documentation
Number of Channels	8 Digital Inputs
Logic Level	24V DC
Input Type	Sourcing, compatible with 3-wire sensors
Operating Temperature	-40°C to 70°C
Compatibility	NI CompactDAQ and CompactRIO chassis
Update Time	7 µs

Key benefits: Hot-swappable C Series design, supports 3-wire sensors, wide -40°C to 70°C operating range, fast 7 µs update time, seamless NI chassis integration

Typical applications: Machine condition monitoring, switch and valve status detection, industrial sensor reading, test stand automation, production line diagnostics

Lifecycle: Used condition – mature C Series product, widely available on secondary market with long-term NI platform support

Compatibility

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Industrial components can differ by series, firmware, voltage, network, terminal base, memory, accessories and approvals. A matching front label does not by itself guarantee a drop-in replacement.

Confirm the complete NI 9421 part number and series from the product label.

Send the existing system or application information when compatibility matters.

State quantity, preferred condition, destination and required delivery date.

Include a clear nameplate photo when the revision is uncertain.

Supply condition

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NEW

New product

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SURPLUS

Unused surplus

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REFURBISHED

Refurbished product

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USED

Used product

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Documents & support

Technical references

Manufacturer documentation should be used for engineering, installation, safety and certification decisions. This page supports identification and sourcing; it does not replace the manufacturer manual.

Product questions

Common product questions

Find answers about product identification, compatibility, condition options and quotation requirements.

How can I identify the correct product?

Check the complete part number, series, revision and product label before requesting a quotation.

How should compatibility be confirmed?

Compare the electrical specifications, communication requirements, accessories and existing system documentation.

Which condition options are available?

Products may be offered as new, surplus, refurbished or used. The quotation will state the supplied condition.

What information is needed for a quotation?

Provide the part number, quantity, preferred condition, destination and required delivery date.

Need NI 9421?

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Include quantity, acceptable condition, destination and timing. A label photo helps verify the request.

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