Experiences with power transformers in Southern Electric

The normally quiescent state of electrical transmission and distribution system plant does not draw attention to incipient faults which may develop from the gradual deterioration of the equipment. These faults may be detected during routine maintenance, but the ability to have detailed information on the state-of-health of transmission and distribution system equipment prior to carrying out maintenance work or alterations becomes a significant asset and adds an element of preventative maintenance to the operation of such assets. Here, the author describes how condition monitoring is successfully used in Southern Electric using a cost/benefit approach for the whole population of equipment