IEEE C57.146:2005

1 Overview
  1.1 Scope
  1.2 Purpose
2 Normative references
3 Definitions, acronyms, and abbreviations
  3.1 Definitions
  3.2 Acronyms and abbreviations
4 General theory
  4.1 General
  4.2 Causes of gas formation
  4.3 Application to equipment
  4.4 Establishing baseline data
  4.5 Recognition of a gassing problem
5 Procedures for obtaining samples of silicone liquid from
  the transformer and for laboratory analysis
  5.1 Sampling of silicone liquid
  5.2 Determination of total dissolved gas
  5.3 Determination of individual dissolved gases
6 Suggested operating procedures utilizing the detection and
  analysis of combustible gases
  6.1 General
  6.2 Evaluation of transformer condition using individual and
      TDCG concentrations
  6.3 Determining the operating procedure and sampling interval
      from the TDCG levels
  6.4 Evaluation of possible fault type by the key gas method
Annex A (informative) Gas solubility
Annex B (informative) Key gas sources-based on averages
        from small- and large-scale experiments
      B.1 Thermal fluid
      B.2 Thermal cellulose
      B.3 Electrical partial discharge
      B.4 Electrical arcing
Annex C (informative) Example
Annex D (informative) Bibliography

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.