National Instruments NI-9238

The National Instruments NI-9238 is a high-performance 24-bit, 4-channel voltage input module designed for precise measurement tasks within the C Series family. This module features differential analog input channels and accommodates a measurement range of ±500 mV, making it compatible with a variety of low-voltage sensors, including current transducers and shunts, particularly in high-current applications. When combined with higher-voltage C Series input modules, the NI-9238 is capable of measuring energy and power consumption, suitable for applications such as industrial machine monitoring, appliance testing, power quality analysis, harmonic analysis, and phasor measurements.

The NI-9238 offers robust channel-to-channel isolation up to 250 Vrms and can endure surge voltages of up to 1,500 Vrms, with specifications applicable up to 2000 meters altitude. It supports simultaneous sampling with a maximum sample rate of 50 kS/s per channel and is equipped with an integrated 12.8 MHz frequency master time base for consistent data rate regulation. Each of the four channels boasts an independent 24-bit resolution analog-to-digital converter (ADC), providing a separate signal path to enhance measurement accuracy.

This module exclusively supports DC input coupling and features screw-terminal connectivity, with input impedance exceeding 1 GΩ. Under normal operating conditions, the NI-9238 achieves a low input noise of 3.9 μVrms, while maintaining a gain error of ±0.20% and an offset error of ±0.06% in optimal calibration. It operates within a temperature range of -40 °C to 70 °C, can be stored at temperatures between -40 °C to 85 °C, and withstands random and sinusoidal vibrations of 5 grms and 5 g respectively, at frequencies from 10 to 500 Hz.

The NI-9238 is compatible with the NI-DAQmx driver software, which integrates seamlessly with development environments such as LabVIEW, LabWindows/CVI, and Microsoft Visual C++. Weighing 5.15 ounces, the module is backed by a three-year warranty, with user and maintenance manuals available for download. For pricing information, please contact a sales representative.