ECEN 5053-003 Embedding Sensors and Actuators questions and answers

A. You are using a thermistor with a resistance of 5000Ω at 25.0 °C and with β = 3630. You measure a resistance of 921 ohms. What is the temperature in °C? B. You are deciding between using a thermistor or a class A RTD for measuring the temperature of a critical circuit board of a smart phone near 25°C. The accuracy must be within 0.25°C throughout the range of measurement. Neither speed of response nor component cost is an issue. What type of sensor do you use and why? Find an example online of a sensor that you could use for this application. C. A 100-ohm Class A RTD probe is calibrated at three points for extra precision, with a curve of RTD (T) = RTD0 ((1 + AT +BT2 + CT3(T -100)) where: RTD (T) = the RTD element’s resistance in ohms at temperature T RTD0 = the RTD element’s resistance in ohms at 0°C T = the RTD element’s temperature in °C A = 3.9083 x 10-3 /°C B = -5.775 x 10-7 /°C2 C = 0 if T >= 0°C IF RTD(T) = 116.01 ohms, what is T? D. You are using a Type K thermocouple to measure the temperature of a process that operates in the range of 1000°C to 1100°C. In particular, you know that the thermoelectric voltage is 42.053 mV at 1020°C and 42.440 mV at 1030°C. Having no other data in between, and no way to look up the data on thermocouple tables, what is a good approximation for the thermoelectric voltage at 1027°C? E. You are using a Type K thermocouple to measure the temperature of a semiconductor etch process that operates in the range of 1000°C to 1100°C. The thermistor in your isothermal block (junctions J3 and J4) measures a temperature of 20°C and your voltmeter measures 44.240 mV. What is the temperature T1 of your process? F. Suppose we include the lead resistance in the calculation of temperature for a class A RTD. If R3 = 1000 ohms, Ra = 20 ohms, V0 = 1.75 ohms, and V = 5 volts, what is the nominal temperature measured. Given the tolerances, what is the highest temperature you could measure