2. Classification and numerical data for liquid dielectrics

As the choice of a classification system for insulating liquids is arbitrary, we will use the one based on their origin [D 4 250][D 4 271] .

• Category I: vegetable oils

  They are essentially composed of triglycerides. Their composition is relatively simple (a few dozen molecules). They are produced from renewable resources (plants).

• Category II: mineral oils

  Derived from the refining of paraffinic, naphthenic or mixed petroleum crudes, they are also "natural" but non-renewable products. These oils are composed of several thousand different molecules. The content of potentially toxic aromatic compounds is minimized...