National Instruments cFP-SG-140 Strain/Bridge Input Module  

The cFP-SG-140 is a Strain/Bridge Input Module for Compact FieldPoint designed by National Instruments. The cFP-SG-140 is available under part number 777318-140. This module is used to measure full/half bridge strain gauges and is compatible with different sensors that are bridge-based. The NI cFP-SG-140 is a plug-and-play module, which means that the system can automatically detect modules. Thus, it offers a simple installation solution. The module needs little maintenance since it has an onboard diagnostic feature. The cFP-SG-140 also features a built-in excitation mode, which supports different programmable excitation levels. To ensure precise and accurate measurements, the cFP-SG-140 can be calibrated.

The cFP-SG-140 Strain/Bridge Input Module has eight differential input terminals. The ADC resolution of the input terminal is 16 bits. A delta-sigma ADC is used in the cFP-SG-140. The impedance of the input terminals is 20 MΩ. The built-in excitation is user selectable and has different excitation voltages. The supported voltage levels are 2.5 V, 5 V, and 10V. The NI cFP-SG-140 is a low noise module with different noise filters. The user can select any filter depending upon the application requirement. The cFP-SG-140 features 15 Hz, 60 Hz, and 240 Hz filters. The range for the update time of all channels is 0.9 sec to 1.15 sec. Also, the device has a channel update rate of 1.11 to 0.87 Hz.

The NI cFP-SG-140 can withstand 2300 Vrms of transient voltage. The continuous isolation voltage is up to 250 Vrms. The adjacent channels of the module are not isolated. The cFP-SG-140 has two green and eight red indicator lights. The green LEDs are for POWER and READY status indication. The red lights are associated with input channels. These lights indicate the overcurrent state of corresponding channels.

The cFP-SG-140 weighs 3.7 oz, and measures 4.3 x 4.2 x 3.6 in. in physical dimensions. The NI device has recommended operating and storage temperature ranges of –40 to 70 °C and –55 to 85 °C respectively, a non-condensing relative humidity range of 10 to 90%, random and sinusoidal operating vibrations of 5 grms and 5 g respectively – all at a frequency range of 10 to 500 Hz.