{"id":781,"count":1,"description":"
\r\n

NI C Series Dynamic Signal Modules<\/h2>\r\n\r\n
\r\n

NI C Series Dynamic Signal Modules acquire vibration, acoustic, IEPE accelerometer, microphone, pressure and other time-varying analog signals. They combine low-noise analog input, simultaneous sampling, anti-alias filtering and sensor-specific conditioning for compatible CompactDAQ and CompactRIO systems.<\/p>\r\n\r\n

These modules are used when signal bandwidth, phase accuracy, dynamic range and continuous sample timing are more important than the slower scan rates used for temperature or general process monitoring. Select the module from the sensor\u2019s electrical output, required frequency range, active channel count and synchronization requirement.<\/p>\r\n <\/div>\r\n\r\n

What Is a C Series Dynamic Signal Module?<\/h3>\r\n\r\n

A C Series dynamic signal module is a specialized analog input module for continuously changing signals such as acceleration, sound, vibration, dynamic pressure and voltage waveforms. It typically uses simultaneous sampling so that the timing relationship between channels is preserved.<\/p>\r\n\r\n

Dynamic signal modules can include functions such as IEPE constant-current excitation, AC or DC coupling, anti-alias filtering, TEDS support on selected models and high-resolution conversion. The appropriate architecture depends on whether the connected sensor is IEPE, voltage output, charge output or externally conditioned.<\/p>\r\n\r\n

\r\n

IEPE and charge-mode piezoelectric sensors are not interchangeable. IEPE sensors contain integrated electronics and require constant-current excitation. Charge-mode sensors require charge-capable conditioning or an external charge amplifier unless the selected input path explicitly supports charge measurement.<\/p>\r\n <\/div>\r\n\r\n

Dynamic Signal Input Types<\/h3>\r\n\r\n
\r\n \r\n \r\n \r\n \r\n \r\n \r\n \r\n \r\n \r\n
Input Architecture<\/th>\r\n Typical Sensor Output<\/th>\r\n Key Functions to Confirm<\/th>\r\n \u0422\u0438\u043f\u0438\u0447\u043d\u044b\u0435 \u043f\u0440\u0438\u043c\u0435\u043d\u0435\u043d\u0438\u044f<\/th>\r\n <\/tr>\r\n <\/thead>\r\n
IEPE Dynamic Input<\/td>\r\n IEPE accelerometer, microphone, force sensor or pressure sensor<\/td>\r\n Constant-current excitation, AC\/DC coupling, input range, TEDS and sensor bias monitoring<\/td>\r\n Vibration, acoustics, NVH, modal analysis and condition monitoring<\/td>\r\n <\/tr>\r\n
Dynamic Voltage Input<\/td>\r\n Voltage output from an external conditioner, amplifier or dynamic transducer<\/td>\r\n Input range, coupling, common-mode limits, anti-alias filter and input impedance<\/td>\r\n Voltage waveform measurement, dynamic pressure and externally conditioned sensors<\/td>\r\n <\/tr>\r\n
High-Channel-Count Dynamic Input<\/td>\r\n Multiple simultaneous dynamic voltage or sensor channels<\/td>\r\n Channel density, aggregate data rate, phase matching and storage throughput<\/td>\r\n Structural testing, machine monitoring and multichannel acoustic arrays<\/td>\r\n <\/tr>\r\n
High-Bandwidth Dynamic Input<\/td>\r\n Rapidly changing analog waveforms<\/td>\r\n Sample rate, usable bandwidth, anti-alias performance and continuous streaming capability<\/td>\r\n Impact testing, transient capture, rotating machinery and high-frequency vibration<\/td>\r\n <\/tr>\r\n
Conditioned Dynamic Sensor Input<\/td>\r\n Voltage from a charge amplifier or external signal conditioner<\/td>\r\n Conditioner gain, output range, coupling, grounding and calibration scaling<\/td>\r\n Charge-mode sensors, hydrophones and specialized dynamic transducers<\/td>\r\n <\/tr>\r\n <\/tbody>\r\n <\/table>\r\n <\/div>\r\n\r\n

Representative NI C Series Dynamic Signal Modules<\/h3>\r\n\r\n
\r\n \r\n \r\n \r\n \r\n \r\n \r\n \r\n \r\n \r\n
\u041c\u043e\u0434\u0435\u043b\u044c<\/th>\r\n Unique Category<\/th>\r\n Key Differentiator<\/th>\r\n Best Fit<\/th>\r\n <\/tr>\r\n <\/thead>\r\n
NI-9230<\/td>\r\n Dynamic Voltage Input<\/td>\r\n Dynamic analog voltage acquisition architecture<\/td>\r\n Conditioned vibration, voltage waveform and general dynamic signal measurement<\/td>\r\n <\/tr>\r\n
NI-9231<\/td>\r\n High-Channel-Count Dynamic Voltage Input<\/td>\r\n Multiple dynamic voltage channels for synchronized acquisition<\/td>\r\n Multichannel waveform measurement, structural testing and distributed sensor systems<\/td>\r\n <\/tr>\r\n
NI-9232<\/td>\r\n IEPE Dynamic Signal Input<\/td>\r\n Integrated conditioning for compatible IEPE dynamic sensors<\/td>\r\n Accelerometer, microphone and vibration measurements<\/td>\r\n <\/tr>\r\n
NI-9233<\/td>\r\n IEPE Dynamic Signal Input<\/td>\r\n Dedicated IEPE sensor acquisition architecture<\/td>\r\n Sound, vibration and dynamic pressure applications<\/td>\r\n <\/tr>\r\n
NI-9234<\/td>\r\n Simultaneous IEPE Dynamic Signal Input<\/td>\r\n Simultaneous dynamic acquisition with IEPE sensor support<\/td>\r\n Vibration, acoustic, modal and rotating-machinery analysis<\/td>\r\n <\/tr>\r\n <\/tbody>\r\n <\/table>\r\n <\/div>\r\n\r\n

This table represents common dynamic signal architectures rather than every C Series module that can acquire a changing analog signal. Confirm the exact model, sensor interface, bandwidth, accessory and software support before ordering.<\/p>\r\n\r\n

How to Choose a C Series Dynamic Signal Module<\/h3>\r\n\r\n

1. Identify the Sensor Electrical Interface<\/h4>\r\n\r\n

Start with the sensor datasheet. Confirm whether the sensor output is IEPE, charge, conditioned voltage, differential voltage or another interface. Also record the nominal sensitivity, maximum output, required excitation, frequency range, connector type, cable type and grounding arrangement.<\/p>\r\n\r\n

An accelerometer described only as \u201cpiezoelectric\u201d cannot be matched to a module until its output type is known. IEPE sensors need constant-current excitation, while charge-mode sensors normally need an external charge amplifier or a charge-capable input path.<\/p>\r\n\r\n

2. Select the Required Bandwidth<\/h4>\r\n\r\n

Define the highest frequency that must be measured accurately, then select a module whose usable bandwidth and anti-alias filtering support that requirement. Do not select from maximum sample rate alone.<\/p>\r\n\r\n

The sample rate must be high enough to support the required measurement bandwidth, but filtering, noise, phase response and storage capability also affect useful dynamic performance. Allow margin for filter transition bands and unexpected higher-frequency content.<\/p>\r\n\r\n

3. Determine Channel Count and Simultaneous Sampling<\/h4>\r\n\r\n

Simultaneous sampling is critical when the phase relationship between channels matters. Examples include modal testing, order analysis, transfer-function measurement, array microphones, multiaxis vibration, force-and-response measurements and rotating-machinery analysis.<\/p>\r\n\r\n

For each channel, confirm the required sensor type, range, sensitivity and cable connection. A multichannel system can require different input ranges or sensor configurations even when all channels measure the same physical phenomenon.<\/p>\r\n\r\n

4. Check Dynamic Range and Noise<\/h4>\r\n\r\n

Dynamic range depends on input noise, gain, converter performance, sensor sensitivity, cable noise and the selected input range. A high-resolution converter does not guarantee useful low-level measurement performance if the sensor or installation introduces excessive noise.<\/p>\r\n\r\n

Select an input range that accommodates the largest expected signal while keeping small signals above the system noise floor. Include overload conditions such as impacts, startup transients and mechanical shocks.<\/p>\r\n\r\n

5. Confirm IEPE Excitation and Coupling<\/h4>\r\n\r\n

For IEPE sensors, verify the required constant-current excitation, acceptable compliance voltage, sensor bias behavior and whether AC or DC coupling is required. AC coupling removes DC bias and very low-frequency content, while DC coupling is needed when the application must retain those components.<\/p>\r\n\r\n

Do not connect a sensor with external power or a non-IEPE output to an IEPE excitation source without verifying the wiring and voltage limits.<\/p>\r\n\r\n

6. Review Synchronization and Data Streaming<\/h4>\r\n\r\n

Dynamic measurements can generate substantial continuous data. Calculate the expected payload rate using:<\/p>\r\n\r\n

Data rate = active channels \u00d7 sample rate \u00d7 transferred bytes per sample.<\/strong><\/p>\r\n\r\n

Verify chassis bandwidth, host memory, storage speed, network capability and application buffering for the complete acquisition duration. For synchronized systems, also define shared clocks, start triggers, reference timing and timestamp requirements.<\/p>\r\n\r\n

IEPE Sensor Measurement<\/h3>\r\n\r\n

IEPE sensors are widely used for accelerometers, microphones, force transducers and dynamic pressure sensors. The sensor contains integrated electronics and is powered through a constant-current supply on the same cable used for the measurement signal.<\/p>\r\n\r\n

Before selecting an IEPE module, confirm:<\/p>\r\n\r\n