Sailing Glossary - Term Thermocouple

A temperature-sensing element which converts thermal energy directly into electrical energy. In its basic form it consists of two dissimilar metallic conductors connected in a closed loop. Each junction forms a thermocouple. If one thermocouple is maintained at a temperature different from that of the other, an electrical current proportional to this temperature difference will flow in the circuit. The value varies with the materials used. Couples of copper and constantan, which generate approximately 40 microvolts per °C of couple temperature difference, are often used for meteorological purposes.