描述
产品概述
NI 9230是National Instruments（NI）推出的一款高精度、多通道动态信号采集模块，属于CompactDAQ（cDAQ）或CompactRIO（cRIO）系列。它专为声学、振动、旋转机械等动态信号测量设计，支持同步采集多路加速度计、麦克风等传感器信号，并提供内置抗混叠滤波和IEPE（集成电子压电）信号调理功能。该模块通过NI-DAQmx驱动与LabVIEW、C/C++等软件无缝集成，广泛应用于结构健康监测、声学测试、旋转机械分析等领域。
核心功能
多通道同步采集
提供4路差分模拟输入通道，支持通道间同步采样，确保多传感器数据的时间一致性。
每通道独立配置IEPE激励（恒流源）和信号调理，兼容大多数压电式传感器（如加速度计、麦克风）。
动态信号优化设计
内置抗混叠滤波器：每通道配备4阶低通滤波器，截止频率可软件配置（最高20 kHz），有效抑制高频噪声。
高动态范围：102 dB动态范围（典型值），支持小信号（如微振动）与大信号（如冲击）的同步测量。
IEPE信号调理
提供2 mA或4 mA恒流激励（软件可选），兼容不同品牌传感器（如PCB、Brüel&Kjær）。
输入阻抗：≥10 GΩ（差分模式），减少对传感器负载的影响。
高精度测量
分辨率：24位（16,777,216计数），可检测纳伏级信号变化。
采样率：单通道最高51.2 kS/s，多通道时采样率均分（如4通道时约12.8 kS/s/通道）。
绝对精度：±0.002%读数（典型值，25°C），满足精密测试需求。
触发与同步功能
支持软件触发、硬件数字触发（TTL电平）和外部时钟同步，可与其他NI模块（如数字I/O、计数器）或第三方设备协同工作。
提供FPGA兼容接口（需搭配cRIO机箱），实现自定义实时信号处理。
技术规格
参数规格
通道数4路差分（支持IEPE激励）
分辨率24位
最大采样率51.2 kS/s（单通道），多通道时均分
输入范围±5 V（固定范围，IEPE传感器输出通常在此范围内）
IEPE激励电流2 mA或4 mA（软件可配置）
抗混叠滤波4阶低通，截止频率可调（最高20 kHz）
动态范围102 dB（典型值）
触发方式软件触发、硬件数字触发（上升沿/下降沿）、外部时钟同步
连接方式50针D-SUB连接器（兼容NI cDAQ/cRIO机箱）
电源需求由cDAQ/cRIO机箱供电（无需外部电源）
温度范围-40°C至70°C（工业级型号，扩展温度范围）
软件支持NI-DAQmx驱动，兼容LabVIEW、C/C++、Python、MATLAB等
应用场景
结构健康监测
采集加速度计信号，分析桥梁、建筑、风力发电机叶片的振动模态和疲劳损伤。
声学测试
连接麦克风，测量噪声水平、声压级（SPL）或进行声学指纹分析（如发动机噪声诊断）。
旋转机械分析
同步采集转速传感器和振动信号，进行阶次跟踪（Order Tracking）和故障诊断（如轴承缺陷、齿轮磨损）。
Product Overview
NI 9230 is a high-precision,multi-channel dynamic signal acquisition module launched by National Instruments(NI),which belongs to the CompactDAQ(cDAQ)or CompactRIO(cRIO)series.It is designed for dynamic signal measurement such as acoustics,vibration,and rotating machinery.It supports the synchronous acquisition of multiple sensor signals such as accelerometers and microphones,and provides built-in anti-aliasing filtering and IEPE(integrated electronic piezoelectric)signal conditioning functions.This module is seamlessly integrated with LabVIEW,C/C++and other software through the NI-DAQmx driver,and is widely used in structural health monitoring,acoustic testing,rotating machinery analysis and other fields.
Core Function
Multi-channel Synchronous Acquisition
Provides 4 differential analog input channels,supports synchronous sampling between channels,and ensures the time consistency of multi-sensor data.
Each channel is independently configured with IEPE excitation(constant current source)and signal conditioning,and is compatible with most piezoelectric sensors(such as accelerometers and microphones).
Dynamic signal optimization design
Built-in anti-aliasing filter:Each channel is equipped with a 4th-order low-pass filter with software-configurable cutoff frequency(up to 20 kHz),which effectively suppresses high-frequency noise.
High dynamic range:102 dB dynamic range(typical value),supports simultaneous measurement of small signals(such as micro-vibration)and large signals(such as impact).
IEPE signal conditioning
Provides 2 mA or 4 mA constant current excitation(software selectable),compatible with sensors of different brands(such as PCB,Brüel&Kjær).
Input impedance:≥10 GΩ(differential mode)to reduce the impact on sensor load.
High-precision measurement
Resolution:24 bits(16,777,216 counts),which can detect nanovolt-level signal changes.
Sampling rate:Up to 51.2 kS/s for a single channel,and the sampling rate is evenly divided for multiple channels(such as about 12.8 kS/s/channel for 4 channels).
Absolute accuracy:±0.002%reading(typical,25°C),meeting precision test needs.
Trigger and synchronization functions
Support software trigger,hardware digital trigger(TTL level)and external clock synchronization,and can work with other NI modules(such as digital I/O,counters)or third-party devices.
Provides FPGA-compatible interface(needs to be used with cRIO chassis)to implement custom real-time signal processing.
Technical specifications
Parameter Specifications
Number of channels 4 differential(supports IEPE excitation)
Resolution 24 bits
Maximum sampling rate 51.2 kS/s(single channel),time-averaged for multiple channels
Input range±5 V(fixed range,IEPE sensor output is usually within this range)
IEPE excitation current 2 mA or 4 mA(software configurable)
Anti-aliasing filter 4th order low-pass,adjustable cutoff frequency(up to 20 kHz)
Dynamic range 102 dB(typical)
Triggering method Software trigger,hardware digital trigger(rising/falling edge),external clock synchronization
Connection method 50-pin D-SUB connector(compatible with NI cDAQ/cRIO chassis)
Power requirements Powered by cDAQ/cRIO chassis(no external power supply required)
Temperature range-40°C to 70°C(industrial model,extended temperature range)
Software support NI-DAQmx driver,compatible with LabVIEW,C/C++,Python,MATLAB Etc.
Application scenarios
Structural health monitoring
Acquire accelerometer signals to analyze vibration modes and fatigue damage of bridges,buildings,and wind turbine blades.
Acoustic testing
Connect microphones to measure noise levels,sound pressure levels(SPL),or perform acoustic fingerprint analysis(such as engine noise diagnosis).
Rotating machinery analysis
Synchronously collect speed sensors and vibration signals for order tracking and fault diagnosis(such as bearing defects and gear wear).
