The NI 9234 is a 4-channel, 24-bit IEPE input module for high-accuracy vibration and acoustic measurements. It delivers simultaneous sampling at up to 51.2 kS/s per channel with built-in IEPE conditioning optimized for accelerometers and microphones. The module combines low noise performance, software-selectable AC/DC coupling, and automatic anti-aliasing filtering across a wide dynamic range. It integrates into NI CompactDAQ, CompactRIO, and USB carrier platforms for machine condition monitoring, noise and vibration analysis, and NVH applications.
Technical Specifications
• Channels: 4 analog inputs, simultaneous sampling
• Resolution: 24 bits
• Maximum Sampling Rate: 51.2 kS/s per channel
• Voltage Range: ±5 V
• Dynamic Range: 97 dBFS at 51.2 kS/s (50 μVrms noise); 99 dBFS at 25.6 kS/s (40 μVrms noise); 103 dBFS at 2.048 kS/s (25 μVrms noise)
• Noise Density: 310 nV/√Hz at 51.2 kS/s; 350 nV/√Hz at 25.6 kS/s; 780 nV/√Hz at 2.048 kS/s
• Input Impedance: 305 kΩ differential; 50 Ω AI– to chassis ground
• IEPE Excitation: Software-selectable 0 or 2 mA (typical 2.1 mA); 19 V max compliance voltage
• Input Coupling: Software-selectable AC/DC
• Overvoltage Protection: ±30 V with respect to chassis ground for IEPE connections
• Anti-Aliasing Filters: Built-in, automatically adjusting to sampling rate
• Cutoff Frequency: 0.5 Hz
• Master Timebase: 13.1072 MHz internal; ±50 ppm accuracy; external timebase input/output supported
• TEDS Support: IEEE 1451.4 TEDS Class I smart sensors
– Key Features
• Front connection via 4 × BNC connectors
• Compact form factor: 140.66 mm L × 88.12 mm H × 25.34 mm D; 173 g
• Conformal coating option available (part number 779680-03)
• NI-DAQmx 9.2 or later; compatible with LabVIEW, LabWindows/CVI, C/C++, C#, Visual Basic .NET
– Typical Applications
• Machine condition monitoring and predictive maintenance
• Noise and vibration analysis
• NVH (noise, vibration, harshness) testing
• Acoustic and vibration measurement systems
– Compatibility & Integration
Supported platforms include NI CompactDAQ, CompactRIO, and the NI USB-9162 single-module USB carrier.
