RTDs are typically connected with other fixed resistors
a. in a pi configuration b. In a bridge configuration c. and capacitors in a filter-type circuit d. and variable resistors
The correct answer and explanation is:
The correct answer is b. In a bridge configuration.
A Resistance Temperature Detector (RTD) is often used to measure temperature by correlating the temperature to the resistance of the RTD element. RTDs typically consist of a pure metal, such as platinum, which exhibits a predictable change in resistance with temperature.
To measure this resistance precisely, RTDs are often part of a bridge circuit, specifically a Wheatstone bridge. A Wheatstone bridge is a circuit used to measure an unknown resistance by balancing two legs of a bridge circuit. In this case, one leg of the bridge contains the RTD, and the other legs contain resistors. The change in resistance of the RTD, due to temperature variation, causes an imbalance in the bridge. This imbalance can be measured as a voltage difference, which is then related to the temperature.
In practice, RTDs are connected in a bridge configuration to achieve high accuracy and stability in temperature measurements. A bridge circuit can be used to measure small changes in resistance, which is essential when detecting subtle temperature changes. The use of the bridge circuit minimizes the effects of lead resistance and provides a more accurate temperature measurement by detecting very small changes in resistance.
Other configurations, like the use of fixed resistors, capacitors, or variable resistors, are not typically used with RTDs for the purpose of temperature measurement. While variable resistors or potentiometers could theoretically be used to adjust the bridge balance, they are not an integral part of the typical RTD measurement setup. Similarly, capacitors are generally not used in the direct measurement of temperature with RTDs.