What are the advantages and disadvantages of oil filled cables?

Some of the advantages and disadvantages of oil filled cables are listed below:

Advantages:

  • Smaller overall size and smaller weight for given voltage and kVA rating due to reduction in the thickness of the dielectric required
  • No ionization, oxidation and formation of voids
  • More perfect impregnation
  • Smaller thermal resistance due to decrease in the dielectric thickness, so higher current rating
  • More maximum permissible stresses
  • Fault identification is easy

Disadvantages:

  • Greater cost
  • Complicated laying of cables and maintenance