Description
The NI-9421 is a robust component belonging to the C Series Digital I/O category, designed to handle complex digital input tasks with ease. This model is available under several part numbers, including 779002-01, 779136-01, 779136-02, and 783734-01, with the 779136-02 being specifically conformal coated for additional protection against harsh environments.
Equipped with 8 digital input channels, the NI-9421 is capable of sinking input types, making it versatile for various applications. It supports logic levels of 12V and 24V, accommodating a broad range of signals. The module ensures reliability through channel to earth ground isolation, rated at 250 Vrms for part numbers 779002-01 and 783734-01, and 60 VDC for part numbers 779136-01 and 779136-02.
In terms of efficiency, the power consumption of the NI-9421 is optimized with up to 240 mW during active use and a maximum of 7 mW in sleep mode, indicating its energy-efficient design. The module’s physical attributes include a weight of 5.1 oz, showcasing its lightweight yet durable construction.
The operating temperature range of -40 °C to 70 °C and storage temperature range of -40 °C to 85 °C ensure the NI-9421 can withstand extreme conditions without compromising performance. Humidity resilience is also a key feature, with operating humidity ranging from 10% RH to 90% RH, non-condensing, and storage humidity from 5% RH to 95% RH, non-condensing.
Furthermore, the NI-9421 is built to endure significant vibration without loss of function. It can withstand operating vibrations up to 5 grms (10 to 500 Hz) under random conditions and 5 g (10 to 500 Hz) under sinusoidal conditions, highlighting its robustness and reliability in challenging industrial settings.
| Specification | Detail |
|---|---|
| Model | NI-9421 |
| Category | C Series Digital I/O |
| Part Numbers | 779002-01, 779136-01, 779136-02, 783734-01 |
| Conformal Coated Part Number | 779136-02 |
| Digital Input Channels | 8 |
| Input Type | Sinking |
| Logic Levels | 12V, 24V |
| Channel to Earth Ground Isolation | 250 Vrms (779002-01, 783734-01), 60 VDC (779136-01, 779136-02) |
| Power Consumption | Active: up to 240 mW, Sleep Mode: 7 mW max |
| Weight | 5.1 oz |
| Operating Temperature Range | -40 °C to 70 °C |
| Storage Temperature Range | -40 °C to 85 °C |
| Operating Humidity Range | 10% RH to 90% RH, non-condensing |
| Storage Humidity Range | 5% RH to 95% RH, non-condensing |
| Operating Vibration (Random) | 5 grms (10 to 500 Hz) |
| Operating Vibration (Sinusoidal) | 5 g (10 to 500 Hz) |
Question 1: How many input channels does the NI-9421 have?
Answer 1: It has 8 sinking input channels.
Question 2: What logic levels does the NI-9421 support?
Answer 2: Supports 12V and 24V logic levels.
Question 3: Is there a conformal coated option for the NI-9421?
Answer 3: Yes, part number 779136-02 is conformal coated.
Question 4: What is the operating temperature range of the NI-9421?
Answer 4: -40 °C to 70 °C.
Question 5: What vibration levels can the NI-9421 withstand?
Answer 5: Up to 5 grms (10 to 500 Hz) under random conditions.


