TEMPERATURE CONTROLLER

PURPOSE:To reduce a temperature detector/temperature detecting cable and a temperature control unit, etc., of thermocouple, etc. by utilizing that a heat sensitive resistance element (PTC) also has the functions of the temperature detector and the temperature control unit. CONSTITUTION:A vessel, equipment and piping, etc., are needed to be previously heated to be in a specified temperature in a fast breeder, etc., and it is realized by using an electric heater 2 consisting of the PTC. If the temperature of the piping 1 is lower than a curie point which is decided by the composition of the PTCs, the resistance value of the electric heater 2 becomes comparatively small, so that the electric heater 2 generates heat by applying a current so as to heat the piping 1. But if the temperature of the piping 1 becomes higher than 300 deg.C, the resistance value of the electric heater 2 remarkably increases to cut off the current. Therefore, the electric heater 2 stops the generation of heat and the temperature of the piping 1 lowers by radiating heat from the piping 1. It is possible to hold the previously heated temperature by repeating the above-mentioned operation.