The Hot Spot Rise Simulator

The Hot Spot Rise Simulator provides a means for obtaining improved accuracy and dependability in the indication of hot-spot temperatures in electric power equipment. When used in connection with the operation of transformers, it avoids the difficulties experienced with earlier types of hot-spot indicators by restricting the apparatus mounted within the transformer to a rugged thermojunction and by limiting the remaining equipment to a thermocouple potentiometer and the Rise Simulator device itself. To insure that this method would not lead to large errors under extreme ambient temperature conditions, calculations were made of the effects of variations in top-oil temperature and load current over a wide range. The errors so calculated are less than the probable uncertainty inherent in the determination of hot-spot temperatures from heat run data.