Contact thermometers differ from regular thermometers in that they are connected to a heating coil, and are hence able to both sense and control the current temperature. In doing so, they allow experiments to be performed under a constant temperature. Contact thermometers work using a negative feedback loop: once the desired temperature has been reached, the heating coil is deactivated; when the temperature falls, the heating coil is reactivated.
Termometro normalak ez bezala, kontaktuzko termometroak berotasun- haril batera konektatuta dauden eta uneko tenperatura atzemateaz gain hau kontrolatzeko gaitasuna dute. Horrela eginez, tenperatura konstantepean esperimentuak egitea uzten du. Kontaktuzko termometroek berrelikadura negatiboa erabiliz funtzionatzen dute: nahi den tenperaturara iristen denean, berotasun- harila desaktibatzen da, eta tenperatura jeisten hastean berotasun- harila berraktibatzen da.