HEAT-SIGNALLING FOIL

摘要

The invention relates to a heat-signalling foil and to the use thereof for studying the evolution of the thermal condition in electrical equipments and installations. According to the invention, the foil comprises a solid support made of porous paper with a thickness of 0.5...0.8 mm, impregnated with a mixture consisting of an aqueous solution of cobalt chloride and aqueous solution of calcium chloride in a 1:1 ratio. In order to be used, the claimed foil is humectated and deposited on the outer surface of a glass vessel (2), filled with liquid (3) with high thermal conductivity, wherein there is immersed a resistor (4) connected to a supply source (5), the evolution of the thermal condition in the vessel (2) being monitored depending on the colour changing from pink to blue, due to the removal of water by evaporation.