This document describes the application of the RCM - Reliability-Centered Maintenance (MCC – Manutenção Centrada na Confiabilidade) methodology to power transformers immersed in liquid insulation, such as mineral or vegetal oil. All standardized RCM phases are documented, including:

1. Instalation Selection;
2. Systems Identification;
3. Components Identification;
4. Functions Identification;
5. Functional Failures Identification;
6. Failure Modes Idenfication;
7. Failure Modes And Effects Analysis (FMEA);
8. Activities Selection;
9. Periodicities Selection;
10. Maintenance Plan.

The study is the result of a Pilot Project from a Joint Working Group (B3.01) from Study Committees CE-B3 (Substations), CE-B5 (Protection and Automation) and CE-A2 (Transformers) of Cigré-Brazil. The project aimed to research the application of RCM to large power transformers, and to serve as reference to the application of the methodology to other types of electric equipments.