NI-9421
Starting at $206.00
779136-01
779136-02
779002-01
783734-01
24 V, 8-Channel (Sinking Input), 100 µs C Series Digital Module
Overview
The NI-9421 works with industrial logic levels and signals to connect directly to a wide array of industrial switches, transducers, and devices. Each channel is compatible with 24 V logic levels and has an LED indicating the state of that channel. The NI-9421 offers isolation between the input channels and earth ground.
Included Items
- Module
- 10-position spring terminal plug (NI-9980) (Included only with Spring Terminal module, part number 783734-01)
- Safety, Environmental, & Regulatory documentation
Part Numbers (4) Price | 779136-01 | 779136-02 | 779002-01 | 783734-01 |
|---|---|---|---|---|
| NI Lead Time | 8-9 weeks | 8-9 weeks | 8-9 weeks | 8-9 weeks |
| Supported Hardware Platform | C Series | C Series | C Series | C Series |
| Number of Bidirectional Digital Channels | 0 | 0 | 0 | 0 |
| Conformal Coated | No | Yes | No | No |
| Current Flow Direction | Sinking Input | Sinking Input | Sinking Input | Sinking Input |
| Enclosed | Yes | Yes | Yes | Yes |
| Digital I/O Logic Levels | 12 V#24 V | 24 V#12 V | 12 V#24 V | 24 V#12 V |
| Digital I/O Isolation | 60 VDC Ch-Earth Ground Isolation | 60 VDC Ch-Earth Ground Isolation | 250 Vrms Ch-Earth Ground Isolation | 250 Vrms Ch-Earth Ground Isolation |
| Front Connection Type | D-SUB(1) | D-SUB(1) | Screw Terminal(1) | Spring Terminal(1) |
| Number of Digital Input Only Channels | 8 | 8 | 8 | 8 |
| Number of Digital Output Only Channels | 0 | 0 | 0 | 0 |
| Maximum Digital Update Rate | 100 µs | 100 µs | 100 µs | 100 µs |
| Reconfigurable | — | — | — | — |
| Maximum Sample Rate | — | — | — | — |
| Number of Analog Input Channels | — | — | — | — |
| Maximum Analog Update Rate | — | — | — | — |
| Number of Analog Output Channels | — | — | — | — |
| Operating Temperature Range | -40 °C to 70 °C | -40 °C to 70 °C | -40 °C to 70 °C | -40 °C to 70 °C |
| Bus Connection | C Series | C Series | C Series | C Series |
| Maximum Clock Rate | 10 kHz | 10 kHz | 10 kHz | 10 kHz |
| Number of Counters/Timers | — | — | — | — |
| Number of External Clock Inputs | — | — | — | — |
| Relay Type | — | — | — | — |
| Signaling Type | Single-Ended | Single-Ended | Single-Ended | Single-Ended |
| Supports Peer To Peer Streaming | — | — | — | — |
| Product Description | NI 9421 DSUB, 24 V, 100 µs, 8-Ch Sinking DI Module | NI 9421 with DSub 8-Ch 24 V, 100 us, Sinking DI Module,CC | NI 9421 Screw Term, 24 V, 100 µs, 8-Ch Sinking DI Module | NI 9421 Spring Term, 24 V, 100 µs, 8-Ch Sinking DI Module |
NI-9421 Accessories and Software
- Model (Part Number)DescriptionImageCompatible Part NumbersSH25F-25M (192568-01)SH25F-25M-1 25-Pin Female to Male Shielded I/O Cable, 1 m779136-01, 779136-02
- Model (Part Number)DescriptionImageCompatible Part NumbersNI-9924 (781922-01)NI 9924 Front-mount terminal block for 25-pin D-Sub Modules779136-01, 779136-02
- Product (Part Number)DescriptionRecommended use casesFlexLogger Professional (785748-3501)FlexLogger Professional, Subscription License, Download
Recommended for automated, extensible data logging with NI data acquisition (DAQ) hardware. Automate tests using alarms, triggers, and events, and expand capabilities with plug-ins.
Key Features
- Multichassis synchronization—Synchronize multiple NI chassis for accurate, time-aligned measurements across high channel counts.
- Logging triggers—Start, stop, or segment data recording automatically based on sensor thresholds or other conditions to capture only what matters.
- Events—Respond to specific occurrences during a test, such as activating equipment when a condition is met (for example, start cooling fans when temperature exceeds a limit).
- Automation APIs—Control and monitor FlexLogger from external applications (Python, NI LabVIEW, or NI TestStand), enabling integration into larger automated test systems.
- Calculation channels—Perform real-time math on acquired data (averages, RMS, custom formulas) to track derived measurements as the test runs.
- Plug-ins—Extend FlexLogger with custom LabVIEW or Python plug-ins to integrate third-party hardware, perform custom analysis, or connect to lab systems.
- CAN/LIN logging—Acquire and log automotive network data alongside sensor measurements for complete vehicle or subsystem testing.
LabVIEW+ Suite (788509-35)NI LabVIEW+ Suite, Subscription License, DownloadRecommended for engineers building full test and validation systems where modular code development and higher-level frameworks are needed to accelerate development for shorter time to market.
The LabVIEW+ Suite includes the following products:
- NI LabVIEW—Provides a graphical programming environment for test system development, enabling connectivity to any instrument and fully integrated user interfaces.
- NI TestStand—Eliminates the need for time-intensive in-house sequencer development and maintenance by providing an off-the-shelf test management software for validation and production test.
- NI DIAdem—Saves engineers hundreds of hours of manual data analysis and report creation with automation.
- NI FlexLogger™ software—Simplifies data acquisition and data logging with interactive measurement setup for NI DAQ hardware.
- NI InstrumentStudio™ software—Provides a central location for configuration, measurement, and automation.
Resources
Support
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