Product Introduction
The NI-9237 is a 4-channel C Series bridge input module designed for precision strain, load, pressure, torque, and force measurement applications. It provides direct connectivity to bridge-based sensors with integrated signal conditioning, excitation, and high-resolution analog conversion.
Featuring 24-bit ADC resolution, simultaneous sampling, programmable bridge completion, and support for quarter-, half-, and full-bridge configurations, the NI-9237 provides a complete measurement solution for structural testing, industrial monitoring, and mechanical validation systems.
Product Overview
The NI-9237 is part of the National Instruments C Series sensor measurement family and is optimized for strain gauge and bridge-based transducer applications.
Each channel includes an independent 24-bit ADC and supports up to 25 kS/s sampling rate, allowing accurate acquisition of dynamic mechanical signals. The module provides built-in bridge excitation and configurable bridge completion resistors, reducing external conditioning requirements.
Compatible with CompactDAQ and CompactRIO platforms, the NI-9237 integrates with NI-DAQmx, LabVIEW, FlexLogger, and NI Linux Real-Time systems to create scalable mechanical test and measurement solutions.
Key Features
4 Simultaneous Bridge Input Channels
The NI-9237 provides four independent analog input channels for bridge-based sensors.
- 4 differential bridge inputs
- Simultaneous sampling
- Independent ADC per channel
- High-accuracy sensor measurement
- Dynamic signal acquisition
Advantage: Enables synchronized measurement of multiple strain gauges, load cells, and torque sensors.
24-Bit High-Resolution ADC
The module uses high-resolution conversion technology for precise mechanical measurements.
- 24-bit ADC resolution
- High dynamic range
- Low-noise acquisition
- Excellent measurement repeatability
- Precision bridge signal capture
Advantage: Detects small changes in resistance and strain signals for accurate force and structural measurements.
Quarter, Half and Full Bridge Support
The NI-9237 supports multiple strain gauge configurations.
- Quarter-bridge sensors
- Half-bridge sensors
- Full-bridge sensors
- Strain gauge measurement
- Load cell measurement
Advantage: Provides flexibility for different mechanical testing and industrial sensor applications.
Integrated Bridge Excitation
The NI-9237 provides built-in excitation power for bridge sensors.
- Internal bridge excitation
- Programmable excitation settings
- Sensor power management
- Reduced external hardware requirements
- Simplified wiring
Advantage: Reduces system complexity by eliminating separate bridge excitation equipment.
350 Ω Bridge Completion Support
Integrated completion resistors simplify quarter-bridge measurement setups.
- 350 Ω completion resistors
- Quarter-bridge configuration support
- Easy strain gauge connection
- Improved measurement consistency
- Reduced setup time
Advantage: Allows direct connection of common strain gauge sensors without additional bridge completion hardware.
25 kS/s Per Channel Sampling
The NI-9237 supports dynamic mechanical measurements with high-speed acquisition.
- 25 kS/s sampling per channel
- Simultaneous sampling
- Hardware-timed acquisition
- Dynamic strain measurement
- Transient signal capture
Advantage: Captures rapidly changing mechanical signals during vibration, impact, and fatigue testing.
Channel-to-Earth Isolation
Electrical isolation improves measurement reliability in industrial environments.
- Channel-to-earth isolation
- Reduced ground-loop interference
- Improved noise immunity
- Sensor protection
- Industrial deployment capability
Advantage: Provides stable measurements when sensors are installed in electrically noisy environments.
Compact C Series Architecture
The NI-9237 integrates directly with CompactDAQ and CompactRIO systems.
- C Series modular design
- Compact installation
- Flexible chassis expansion
- Mixed sensor system support
- Industrial-ready platform
Advantage: Enables customized measurement systems combining strain, temperature, voltage, and digital control modules.
Technical Specifications
| Parameter | Description |
|---|---|
| Product Type | C Series Bridge Input Module |
| Number of Channels | 4 Differential Bridge Inputs |
| ADC Resolution | 24 Bits |
| Maximum Sampling Rate | 25 kS/s per Channel |
| Input Configuration | Quarter, Half, Full Bridge |
| Bridge Completion | 350 Ω Internal Completion Resistors |
| Bridge Excitation | Built-In Programmable Excitation |
| Sensor Types | Strain Gauge, Load Cell, Pressure, Torque Sensors |
| Isolation | Channel-to-Earth Isolation |
| Supported Platforms | CompactDAQ and CompactRIO |
| Connector Type | Spring Terminal |
| Driver | NI-DAQmx |
| Programming Support | LabVIEW, FlexLogger, Python, C/C++, C#, .NET |
Software Ecosystem
The NI-9237 integrates with NI software tools for mechanical measurement, data acquisition, and automated testing.
- NI-DAQmx: Provides device configuration, acquisition, timing, calibration, and sensor measurement APIs.
- LabVIEW: Enables graphical development of strain, force, and structural testing applications.
- FlexLogger: Provides configuration-based mechanical testing and data logging.
- NI MAX: Supports hardware discovery, diagnostics, and system configuration.
- DIAdem: Provides engineering data analysis and reporting.
- Python, C/C++, C#, .NET: Supports custom measurement software development.
Industries
- Aerospace and Defense
- Automotive Testing
- Structural Engineering
- Industrial Automation
- Mechanical Research
- Energy Systems
- Manufacturing Equipment
- Research Laboratories
Applications
Strain Measurement
The NI-9237 provides accurate strain gauge acquisition for structural analysis.
- Material testing
- Structural testing
- Fatigue analysis
- Load monitoring
Load Cell Measurement
The module directly interfaces with load cells for force measurement applications.
- Force testing
- Weight measurement
- Press monitoring
- Industrial force control
Torque Measurement
Bridge sensor support enables torque measurement in rotating and mechanical systems.
- Motor testing
- Drive system validation
- Mechanical performance analysis
- Rotating equipment testing
Pressure Measurement
The NI-9237 can acquire signals from bridge-based pressure sensors.
- Hydraulic testing
- Pneumatic systems
- Process monitoring
- Fluid system validation
Vibration and Dynamic Testing
High-speed synchronized acquisition supports dynamic mechanical testing.
- Impact testing
- Modal analysis
- Mechanical vibration measurement
- Durability testing
Comparison with Similar Products
| Model | Main Difference | Best Application |
|---|---|---|
| NI-9237 | 4-channel bridge input module with integrated excitation and strain measurement support. | Strain, load, torque, and pressure testing |
| NI-9235 | 4-channel strain/bridge module designed for higher channel-count strain applications. | Structural strain measurement |
| NI-9236 | Bridge input module optimized for quarter and half bridge strain configurations. | Industrial strain measurement |
| NI-9234 | Dynamic signal acquisition module with IEPE sensor support. | Vibration and acoustic measurement |
Recommended Related Products
| NI cDAQ-9185 | Ethernet CompactDAQ chassis for distributed mechanical measurement systems. |
| NI cRIO-9056 | CompactRIO controller supporting C Series strain and measurement modules. |
| NI-9234 | Dynamic signal acquisition module for vibration and acoustic testing. |
| NI-9219 | Universal analog input module supporting multiple sensor types. |
Why Choose NI-9237?
- 4-channel bridge measurement capability
- 24-bit high-resolution ADC
- Quarter, half, and full bridge support
- Integrated bridge excitation
- 350 Ω bridge completion resistors
- 25 kS/s per channel sampling
- Channel-to-earth isolation
- Compact C Series modular architecture
- Compatible with CompactDAQ and CompactRIO
- Ideal for strain, force, torque, and pressure measurement
Frequently Asked Questions
What sensors can NI-9237 measure?
The NI-9237 is designed for bridge-based sensors including strain gauges, load cells, torque sensors, and pressure transducers using quarter-, half-, or full-bridge configurations.
Does NI-9237 provide bridge excitation?
Yes. The NI-9237 includes integrated bridge excitation and internal completion resistors for simplified strain gauge and bridge sensor connections.
What is the difference between NI-9237 and NI-9234?
The NI-9237 is designed for bridge-based sensors such as strain gauges and load cells, while the NI-9234 is optimized for IEPE vibration and dynamic signal sensors.
Conclusion
The NI-9237 4-channel C Series bridge input module provides precision strain and sensor measurement with 24-bit resolution, integrated bridge excitation, quarter/half/full bridge support, and high-speed synchronized acquisition. It is an ideal solution for structural testing, load measurement, torque analysis, pressure monitoring, and mechanical validation systems based on CompactDAQ and CompactRIO platforms.
