Operating Problems of Forced-Oil Forced-Air-Cooled Transformers

The adoption of forced-oil forced-air cooling for large power transformers by the electric industry has created a new problem for the operator of the equipment. The experience of this large utility has been that the supplier has not furnished a self-cooled rating for his product. The problem of determining the self-cooled rating has thus fallen upon the purchaser and the operator of the equipment. This paper discusses the operating problems caused by the partial or complete loss of auxiliary cooling equipment of this type of transformer.