scope:

This Instruction applies to uninhibited insulating oils in transformers, switchgear and similar apparatus where sampling is practicable.

Low oil volume equipment which does not contain a reserve of oil for testing purposes, or equipment which is not designed for the process of routine oil sampling are excluded from this instruction.

Purpose

This Instruction details the periodicity and the necessary testing required to ensure that insulating oil conforms to the British Standard BS 5730:1979, to determine the suitability of the oil for further service and for the detection defects within apparatus not obvious to other forms of inspection.