National Instruments FP-SG-140 Strain-Gauge Input Module

The NI FP-SG-140 (Part Number: 777518-140) is an 8-Channel, FieldPoint Strain-Gauge Input Module. This module can be used to measure values from half-bridge and full-bridge strain gauges, force sensors, load cells, torque sensors, etc. The values from quarter-bridge strain gauges can also be measured with the help of an external completion resister.

To ensure a trouble-free installation, configuration, and maintenance, the NI FP-SG-140 comes with built-in overhanging, excitation, and onboard diagnostics. The kind of excitation used in this strain-gauge module is pulsed excitation, which prevents the unit from self-healing and subsequent erratic measurements. This module consumes its onboard resources for the measurement and linearization of signals and scaled values are forwarded to the user’s monitoring or control software application. With this model, the user can directly connect units under test or industrial sensors to achieve high-accuracy measurements. Moreover, the module’s capability to measure in millivolts per volt enables the NI FP-SG-140 to work with a broad range of process monitoring transducers, such as pressure sensors and load cells.

Up to 21 mA excitation to the channels of the module is turned on and off in pulse pattern. Each channel on the module can be configured for a different excitation voltage level of 2.5 V, 5 V, or 10 V. This module comes equipped with a 16-bit delta-signal analog-to-digital converter (ADC) and a lowpass filter on each channel. This arrangement allows for better accuracy and noise rejection. To fit the user’s application, the NI FP-SG-140 offers a set of three update rates ranging from 0.87 Hz to 1.11 Hz.