check the quality of the transformer oil.jpeg
Susanna Laurén Mar 6, ’24 < 3 min

How to check the transformer oil quality based on ASTM D971 and IEC 62961 standards?

Transformer oil, also known as insulating oil or dielectric oil, is a type of mineral oil that is used in electrical transformers and other electrical equipment. Transformer oil provides insulation between the windings and other electrical components within a transformer. This insulation helps to prevent electrical breakdown and ensures the safe operation of the transformer. In addition, transformer oil helps to dissipate heat that is formed during operation, preventing the transformer from overheating and maintaining optimal operating temperatures.

Transformer oil is typically a highly refined mineral oil, although synthetic oils are also used in some applications. Transformer oil must meet specific standards and specifications to ensure its effectiveness and safety in electrical equipment. Regular testing and maintenance of transformer oil are essential to ensure the reliable operation of transformers and other electrical devices.

For this reason, a multitude of different standardized testing methods have been developed for transformer oil analysis. In this blog post, we look more closely into two different standards ASTM D971 and IEC 62691 which are based on the interfacial tension measurement between water and transformer oil.

Automation ensures ease of use

Although interfacial tension between water and oil can be measured with any tensiometer, Sigma 702 ET enables automated operation. This ensures that the measurement is easy to conduct and performed, in the same way, each time independent of the instrument operator.

Sigma 702 ET has instructions for both ASTM D971 and IEC 62961 embedded into its software which makes it simple to conduct the measurements. The software will guide you through each step of the measurement independent of which standard you decide to follow.

To learn more about the testing of transformer oil quality and see how it can be done in practice, please watch the short video below.


The blog post was originally published on the 5th of Feb, 2019, and has since been updated. 

Related products

   Sigma 702ET Transformer Oil Analyzer specifically designed for measurements of interfacial  tension of transformer oil according to relevant standards.

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