Introduction_to_Sensors_and_Transducers.pptx

Introduction to sensors and transducers. Categories of transducers, selection of transducers based on factors.

1. Introduction to Sensors and Transducers Lecture Notes for Measurement & Instrumentation

2. Introduction - Sensor: detects/measures a physical quantity. - Transducer: converts one form of energy into another. - All sensors are transducers, but not all transducers are sensors. Examples: • Microphone: sound → electrical signal • Loudspeaker: electrical → sound energy

3. Sensor vs Transducer Sensor: - Detects/measures a parameter. - Example: Thermistor. Transducer: - Converts one form of energy to another. - Example: Microphone, Loudspeaker.

4. Characteristics of Transducers - Sensitivity - Linearity - Range - Accuracy - Response time

5. Classification: Energy Conversion 1. Active Transducers (self-generating) • Thermocouple, Piezoelectric sensor 2. Passive Transducers (require excitation) • Strain gauge, LVDT, Thermistor

6. Classification: Quantity Measured - Temperature: Thermocouple, RTD - Displacement: LVDT, Potentiometer - Pressure: Strain gauge, Bourdon tube - Flow: Orifice plate, Turbine meter - Light: Photodiode, LDR

7. Classification: Output Signal - Analog Transducers → Continuous output (e.g., thermocouple voltage) - Digital Transducers → Digital output (e.g., DS18B20 temperature sensor)

8. Classification: Principle of Operation - Resistive (strain gauge, LDR) - Inductive (LVDT) - Capacitive (level sensor) - Optical (encoder) - Piezoelectric (crystals)

9. Applications of Transducers - Industrial automation (temperature, pressure, flow) - Medical devices (ECG, SpO₂, BP monitors) - Automotive (accelerometers, oxygen sensors) - Consumer electronics (microphones, touchscreens)