Several factors affect strain gauges, primarily related to changes in the object to which they are attached and environmental conditions.
According to the reference, variations in temperature significantly affect strain gauge readings.
Temperature Effects on Strain Gauges
Temperature variations influence strain gauges in several ways:
- Thermal Expansion: Temperature changes cause the object under measurement to expand or contract. The strain gauge detects this dimensional change as strain, even if there's no actual stress applied.
- Gauge Resistance Changes: The resistance of the strain gauge itself changes with temperature. Most strain gauges are made from a constantan alloy, but even these materials exhibit some temperature sensitivity.
- Connecting Wire Resistance: The resistance of the wires connecting the strain gauge to the measuring instrument also changes with temperature, which can introduce errors in the strain measurement.
