TFL08 Temperature Instuments

# TFL08 Temperature Instuments - Temperature and Radiation...

This preview shows pages 1–6. Sign up to view the full content.

1 Temperature and Radiation Sensors 2 Unit Objectives • Describe the various methods available to measure temperature • Present the physics associated with the operation of these devices • Examine the issues associated with using common temperature measuring systems

This preview has intentionally blurred sections. Sign up to view the full version.

View Full Document
2 3 Temperature Sensor (Mechanical) Temperature Sensor (Mechanical) • Thermometer (Liquid in Glass) – Mercury (-39 o C to 357 o C) – Alcohol (-117 o C to 79 o C) • Pressure Thermometer • Bimetallic Strip 4 Temperature Sensor (Pneumatics) Temperature Sensor (Pneumatics) • Bimetallic Strip • Expansion Tube Material A (Small ) Material B (Large ) Brass Tube Low Value Core
3 5 Temperature Transducer (Electric) Temperature Transducer (Electric) • Bimetallic Strip • Thermo-Resistive (RTD) •Th e rm i s to r • Thermocouple • Semiconductor – Diode – IC Chip 6 Resistance Temperature Detectors • The resistance of these devices change with temperature • The function that relates temperature to resistance is a polynomial (normally a quadratic), but linear over small ranges • Operating Ranges – Copper: -200 o C to 250 o

This preview has intentionally blurred sections. Sign up to view the full version.

View Full Document
4 7 Thermo-Resistor/Thermistor Thermo-resistive Element V o 5 - 12 V DC R g R v R 2 R 1 R m ( V i ) 8 RTD Analysis I 1 ) ( 1 1 ) ( 2 1 1 2 1 2 1 R R R R R R R R R R R R V R R R R V v g g v m g v i v g o For a Wheatstone bridge the output voltage is a function of the resistances and the input voltage. 1 ) ( 2 1 2 1 R R R R V R R R R V g v i v g o Now let R m →∞
5 9 RTD Analysis II Now let R 1 = R 2 ) ( 2 ) ( v

This preview has intentionally blurred sections. Sign up to view the full version.

View Full Document
This is the end of the preview. Sign up to access the rest of the document.

{[ snackBarMessage ]}

### Page1 / 15

TFL08 Temperature Instuments - Temperature and Radiation...

This preview shows document pages 1 - 6. Sign up to view the full document.

View Full Document
Ask a homework question - tutors are online