scope:

This guide is intended to apply to silicone-immersed transformers in which the silicone fluid was the fluid supplied when the transformer was originally manufactured. This guide also addresses the following:

- The theory of combustible gas generation in a silicone-filled transformer

- Recommended procedures for sampling and analysis

- Recommended actions based on the interpretation of results

- A bibliography of related literature

Purpose

The purpose of this guide is to assist the transformer operator in evaluating dissolved gas analysis (DGA) data obtained for silicone-filled transformers. Other techniques such as fixed instruments and gas space analysis may well have utility for silicone-filled units; however, due to a lack of data at this time, this guide will focus only on DGA.