Strain Gauge is a passive transducer. This is used to measure the lateral strain exerted on a given surface. This sensor converts a mechanical displacement into a change in resistance. Positioning and quality of bonding the sensor on the surface, largely determines the accuracy. An optional external Whetstone's bridge is used to measure bridge imbalance, which is a measure of strain. A bridge is symmetrical, four-element, circuit that enhances the instrument's ability to detect small changes in the sensor. Four Strain gauge sensors arranged in the bridge configuration, balances out fixed or quiescent voltage drop, allowing magnification of the different signal. This acquired signal is conditioned and computed to indicate actual strain suffered by the surface. In the Strain gauge experimental module, the sensor is bonded on one end of a long rectangular stainless steel metal strip of uniform cross section. This end is fixed firmly to a metallic stand. The other end is freely suspended, similar to a Cantilever. To this free end, weights ranging from 50gms to 1000 gms in multiples of 50 gms are added to create strain (elongation) on the strain gauge strip. A relation between applied stress and measured strain gives the change in resistance of the gauge, explaining the principle of strain gauge transducer. This consists of a built-in power supply, interface electronics, assorted weights. A standard digital multimeter in 2V DC range is used to make voltage measurement. This voltage measurement directly indicates the weights added on the strain gauge pan. Specifications: - 4 numbers of 350 (strain elements connected in bridge configuration.
- Strain elements cemented on fixed end of metal bar. The other end is free to move.
- Two strain gauges are mounted on one side of the strip. Two more on the other side of the strip.
- Material of the strip: stainless steel
- Length of the strain gauge foil: 10mm
- Thickness of the strip: 3.5mm
- Supporting line to leading point: 200mm
- Length of the strip: 300mm
- Width of the strip: 25mm
- Excitation voltage: 9V DC
- Built-in power supply.
- Different weights, weighing upto 1Kg supplied.
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