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TRANSFORMER OIL

Transformer oil is a mineral (clean hydrocarbon) oil, which is obtained by refining crude petroleum. It has the following purposes:
  • It provides additional insulation.
  • It carries away the heat generated in the core and the coils.
  • It protects the paper from dirt and moisture.
Transformer oil has the following properties:
  • High dielectric strength.
  • Low viscosity to provide heat transfer.
  • Good resistance to emulsion.
  • It must be free from inorganic acid, alkali and corrosive sulphur.
  • It must have high flash point.
  • It must be free from sludging under normal operating conditions.
The most important factors are:
  • Operating temperature.
  • Atmospheric conditions, particularly inside stations.
  • Electric strength.
  • Moisture and other contamination.
  • Sludge formation.
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