National Instruments SCXI-1125

The National Instruments SCXI-1125 Voltage Input Module (Part Number: 776872-25) is designed to offer robust performance in industrial environments, featuring 300 Vrms of working isolation and integrated low pass filtering for each of its eight analog input channels. This module excels at managing millivolt signals, voltage sources, and current inputs from 0 to 20 mA and 4 to 20 mA, as well as thermocouple applications. It efficiently multiplexes its eight channels into a single channel for data acquisition, while allowing for expansion through additional modules. The SCXI-1125 supports parallel-mode operation, enhancing its output capabilities.

Equipped with calibration hardware to minimize error sources, the module includes programmable offset calibration, where software-controlled analog switches ground the instrumentation amplifier inputs for precise offset error calibration. A built-in EEPROM retains calibration constants for each channel and input range, while also storing unalterable factory calibration constants in permanent memory. This facilitates the use of calibration constants by the NI-DAQ driver software to correct gain and offset errors. The output range is ±5.0 V, and the module measures 7.4 x 6.8 x 1.2 inches and weighs 22.6 ounces.

Each channel features an automatic low pass filter, allowing user-selectable configurations at 4 Hz or 10 kHz. The SCXI-1125 supports irregular scanning, enabling users to select specific channels and scan them in a preferred order. Individual channel isolation is maintained with a common-mode voltage of 300 Vrms between channels and to ground. Additionally, the module is CE certified and meets the double insulated, Category II operational isolation standards.

The NI-DAQmx 9.0 or later driver software is necessary for configuring and programming the SCXI-1125. It is compatible with various application development environments, including LabVIEW, LabWindows/CVI, and Measurement Studio, with configuration support through the Measurement & Automation Explorer tool. Although the SCXI-1125 has been designated as End of Life by National Instruments, it remains available for purchase and repair through Apex Waves.