study of temperature sensitive materials and the use and modellingof a typical bridge circuit used for
A study of temperature sensitive materials and the use and modelling of a typical bridge circuit used for temperature measurements Contents 1. ... Introduction and results of the effect of temperature on the devices 4. ... Graph of the effect of temperature on the resistance of the PT100 10. Graph of applied voltage against the final temperature of the heating resistor 11. Graph of applied power against the final temperature of the heating resistor 12. ... Conclusion A study of temperature sensitive materials and the use and modelling of a typical bridge circuit used for temperature measurements Introduction This report is based on a laboratory involving the temperature tolerances of a platinum resistance temperature sensor incorporated in a wheatstone bridge. At the beginning of that particular laboratory Dr Coles demonstrated the change in resistance for four different materials at two different temperatures one at room temperature by placing the four materials in water at approximately 100ēC (boiling point of water). We were asked to complete a table and make a guess at what the materials were by observing the change in resistances. These are the results Resistance at room temperature Resistance at 100ēC +ve or -ve Type of material? ... Device One 110 Ω 104 Ω -ve This material has a very low temperature coefficient Resistor Device Two 100 Ω @0ēC 138 Ω +ve This is a PT100 temperature sensor as it has a resistance of 100 ohms at 0C Temperature sensor Device Three 55000 Ω 3000 Ω -ve semiconductor NTC thermistor Device Four 73.8 Ω 3300 Ω +ve semiconductor PTC thermistor Device one has a low temperature coefficient because the resistance of the device does not change much with temperature.