TEMP MEASURING INSTRUMENTS GLASS THERMOMETER PR GAUGE THERMOMETER

TEMP MEASURING INSTRUMENTS • • GLASS THERMOMETER PR GAUGE THERMOMETER (Liquid vapour and gas) DIFFERENTIAL EXPANSION ( Bimetallic thermometer) ELECTRICAL RESISTANCE ( RTD – Resistance Temp Detector) THERMOCOUPLE PYROMETER OPTICAL PYROMETER RADIATION PYROMETER THERMISTOR

TEMP MEASUREMENT • Temp is thermal state of body. • It is the property , which tells us the degree of hotness or coldness measured along some temp scale • When a body is heated or cooled, various primary effects result. One of these results may be used for temp measurement • Change in physical state or phase ( solid , liquid and vapour) • Change in physical dimension • Variation in electrical properties • Seebeck effect • Bimetallic strip when heated , it bends in a direction of a metal having low coefficient of expansion • Change in intensity of total radiation emitted (PYROMETER) • Change in temp causes change in volume and Pr of gas

LIQUID IN GLASS THERMOMETER LIQUID RANGE( DEGREE CENTRIGRADE) MERCURY -35 TO 510 ALCOHOL -80 TO 70 TOLUENE -80 TO 100 PENTANE -200 TO 30 CREOSOTE -5 TO 200 MERCURY + NITROGEN -95 TO 150 DEGREE F

FILLED SYSTEM THERMOMETER

BIMETAL – STRIP THERMOMETER

BIMETAL – STRIP THERMOMETER

VAPOUR PR THERMAL SYSTEM

VAPOUR PR THERMAL SYSTEM