Abstract: A vaporization cooled transformer of the type comprising a transformer tank in combination with a heat exchanger employs temperature sensing means in both the tank and the heat exchanger for sensing a predetermined temperature differential to indicate the presence of air in the transformer. When the temperature differential exceeds a predetermined range, an alarm and a transformer disconnect relay become actuated. The temperature differential sensor can also be calibrated to provide excess moisture indication above a threshold moisture content caused by the saturation of the molecular sieve water scavenger within the transformer assembly.

Abstract: A vaporization cooled transformer is provided with rectangular windings in which the cooling ducts are integrally formed by pressing the coils with a hydraulic press. The coils are smaller than windings in which cooling channels are formed by insulating spacers. The smaller windings result in a savings in conductor material, core material, fluid, and tank plate.

Abstract: A vaporization cooled transformer utilizes the vaporized coolant at a constant predetermined pressure for upgrading the dielectric strength of the coolant. An auxiliary heater is employed for vaporizing the coolant at low temperature ambient conditions. The constant predetermined pressure is maintained at higher ambient conditions by controlling the cooling capacity of a plurality of heat exchangers.

Abstract: A vaporization cooled transformer of the type comprising a transformer tank in combination with a heat exchanger employs temperature sensing means in both the tank and the heat exchanger for sensing a predetermined temperature differential to indicate the presence of air in the transformer. When the temperature differential exceeds a predetermined range, an alarm and a transformer disconnect relay become actuated. The temperature differential sensor can also be calibrated to provide excess moisture indication above a threshold moisture content caused by the saturation of the molecular sieve water scavenger within the transformer assembly.

Abstract: The invention is a hermetically sealed motor driven pump cooled by a liquid dielectric coolant. The pump has an impeller housing, a motor housing containing a liquid dielectric cooling fluid of the same type as the pumped fluid, and a sealing means between the impeller housing and the motor housing to prevent flow of the pumped fluid from the impeller housing to the motor housing. An electric motor is contained in the motor housing with a shaft extending into the impeller housing and an impeller attached to the shaft inside the impeller housing. A hollow conduit from the discharge port of the impeller housing to the motor housing is used to create a fluid pressure inside the motor housing equal to the pressure of the pumped fluid at the discharge port to increase the heat dissipation. Particles in the pumped fluid are effectively excluded from contacting the bearings. The hollow conduit may contain a filter or desiccant and the motor housing may contain a magnetic plug.

Abstract: The invention is an improved heat exchanger of the type used for cooling electrical apparatus and having a plurality of headers and interconnecting cooling tubes arranged perpendicular to the headers and includes at least one fan to direct air over a portion of the cooling tubes. The improvement in thermal rating is obtained by the use of air deflectors to redirect the airflow over an additional portion of the cooling tubes.

Abstract: A one way flow and return system for vapor cooled transformer heat exchangers employs an inlet coupled with an entrance manifold and an outlet coupled with a return manifold. The incoming vaporized coolant enters the entrance manifold in a first direction of flow and the condensed vapor droplets leave the exit manifold in an opposite flow direction. The arrangement of separate entrance and exit manifolds prevents interference between the incoming vaporized coolant and the returning condensed coolant.