When to Replace aging Transformers Part-2

Part-2 of when to replace aging transformers uses the initial case study to define basic problems surrounding transformers that were in service for more than 60 years. This document will provide an update on transformers returned to service, now 71 years old. It will expound more deeply on the insulation system, testing and criteria used to determine whether to allow a transformer to remain in service or to be replaced. It will explore the technique using Degree of Polymerization to assess remaining life of insulation as defined in the standards. With today’s information gathering techniques and data base manipulation, method of On-Line monitoring will be discussed. Additional information is published in paper titled "When to Replace Aging Transformers" at the 2010 IEEE PCIC Conference [3].