Fundamentals of insulating transformers

In attempting to condense insulation fundamentals for transformers into a short paper, a possible procedure is to recognize the steps ordinarily used in problem solving. This includes definition of the problem, recognize relationships, examine and analyze component parts, plan a method of attack, find a solution based on fundamental principles, appraise the solution and make a decision. From these steps, the reader can proceed to increase his knowledge. General transformer fundamentals will be considered for dry-type and liquid-immersed distribution and power ratings. This will involve 25 kva to 3,000 kva, 5 kv to 15 kv class dry-type transformers, 25 kva to 500 kva, 8.6 kv to 13.8 kv liquid-filled distribution transformers and power ratings above 501 kva through higher voltage classes liquid-filled.