BS EN IEC 60567:2024
Oil-filled electrical equipment. Sampling of free gases and analysis of free and dissolved gases in mineral oils and other insulating liquids. Guidance

Scope: This document deals with techniques for sampling free gas from gas collection relays in power transformers. Three sampling methods are presented. The techniques for the extraction of oil from oil equipment such as transformers, instruments, reactors, bushings, oil-filled cables and tank-type capacitors are not covered by this document but are described in this IEC 60475:2022 (Section 4.2). Gases need to be analysed before they can be extracted from the oil. Three basic methods are presented: one using vacuum extraction, another separating the gases by blowing gas through the oil sample and a final device collecting the sample by separating the gases in the oil-gas mixture, which are analysed quantitatively by gas chromatography; the free gas is analysed directly without treatment. To ensure consistent performance of the oil extraction and gas analysis equipment combination, the method of degassing a laboratory-prepared sample containing known concentrations of gas and then quantifying the gases extracted from it is considered the best method (there are two methods for preparing standard samples). When routine calibration checks of the chromatograph are convenient, standard mixtures containing appropriate amounts of each component can be used.

BS EN IEC 60567:2024 Referenced Document

IEC 60296 Fluids for electrotechnical applications – Mineral insulating oils for electrical equipment
IEC 60475:2022 Method of sampling insulating liquids
IEC 60567:2023 Oil-filled electrical equipment - Sampling of free gases and analysis of free and dissolved gases in mineral oils and other insulating liquids - Guidance
ISO 5725-1 Accuracy (trueness and precision) of measurement methods and results — Part 1: General principles and definitions

2024 BS EN IEC 60567:2024 Oil-filled electrical equipment. Sampling of free gases and analysis of free and dissolved gases in mineral oils and other insulating liquids. Guidance