Transformer maintenance interval management

To protect and extend the life of transformers, information such as load and fault current as well as top-oil or hottest-spot temperatures needs to be collected notification issued when a value has reached a preset level or analysed on a continuous basis. Protective relays that are permanently connected to the transformer current (and possibly temperature inputs) as shown in Fig. 1, have memory and recording capability, and have logical decision making capacity, can be the beginning of a comprehensive “life management” system for transformers, without creating a massive new system.