Experiment 3 - Dynamic Characteristic of Thermistor
Download as DOCX, PDF0 likes330 views
This document provides instructions for an experiment on measuring the dynamic characteristics of a thermistor. The objective is to determine experimentally how the resistance of a thermistor varies over time when a current is passed through it. Students are asked to construct a circuit with a thermistor, resistors and multimeter. They then take readings of the current through the thermistor and one resistor over time, and plot the results on graphs. Finally, students must write a report analyzing the temperature-resistance relationship of the thermistor, comparing the time responses from the graphs, and concluding with the voltage-current characteristic of the thermistor.
Experiment 3 - Dynamic Characteristic of Thermistor
- 1. EEEC6430312 Measurements and Instrumentation Faculty of Engineering and Computer Technology Laboratory Manual Lecturer: Ravandran Muttiah BEng (Hons) MSc MIET Year/Semester: Year 2 / Semester 1 Academic Session: 2020/2021 The information in this documentis important and should be noted by all students undertaking the Bachelor of Engineering (Honours) in Electrical and Electronic Engineering Approved by Coordinator: Endorsed By Dean: ------------------------------------------ __________________
- 2. AIMST University Faculty of Engineering and Computer Technology BEng (Hons) in Electrical and Electronic Engineering Measurements and Instrumentation 1 Experiment 3 - Dynamic Characteristic ofThermistor Objective This experiment is to gain practical experience in self-heating effect on the resistance of a thermistor, to determine experimentally the variation in resistance with time of current in a thermistor and the dynamic characteristics of thermistor. Materials and Apparatus (1) Digital Multimeter (2) Negative Temperature Coefficient (NTC) Thermistor 1 KΩ or 10 KΩ (3) 3 Resistors 50 Ω (4) Resistor 200 Ω (5) Thermometer Procedure Construct the circuit shown in figure 1. Figure 1 𝐼TH is the current through thermistor 𝐼R is the current through 200 Ω resistor R 𝑉R is the voltage across 200 Ω resistor 𝑉TH is the voltage across the thermistor 𝑉L is the voltage across Load resistor (50 or 100 or 150 Ω) I I DMM − 9 VinDC Switch S1 𝑅 = 200 Ω = 𝜋𝑟2 𝑅TH 𝑉L = 50 to 150 Ω 𝑉L 𝑉TH Thermistor Resistor Switch 𝐼TH 𝐼R +
- 3. AIMST University Faculty of Engineering and Computer Technology BEng (Hons) in Electrical and Electronic Engineering Measurements and Instrumentation 2 Make the following measurements and tabulate with reference to time say for upto 10 minutes. Take the readings of time 𝑇, 𝐼TH and 𝐼R for every 20 seconds and tabulate as shown in table 1 below. Then plot the graphs with the readings time 𝑇 and 𝐼TH , and 𝑇 and 𝐼IR. Table 1 Time in Minutes Current Thermistor 𝐼TH Resistor 𝐼R 0 1 2 3 4 5 6 7 8 9 Report Write a laboratory report on this experiment. (1) Explain in detail about the characteristics of relationship between temperature and resistance. (2) Discuss the results that obtained by comparing the characteristics graphs for both the thermistor time response and resistor time response. (3) Show the Voltage-Current characteristic of thermistor and conclude the result.