Transformer oil has to be checked regularly in order to make sure its working quality, and whether it meets the standard or not. Various methods conduct testing. The criteria are established by the ASTM ( American Society for Testing and Materials).
Now, what factors do we check while testing transformer oils in a laboratory?
The standard specification for mineral insulating oil.
Acid number
Liquid power factor
Interfacial tension
Specific resistance
Corrosive sulfur
Visual examination
What is the importance of laboratory testing of oil transformers?
To determine the required electrical properties
To maintain its cleanliness
To know if any filtration is needed
Reduces oil costs
Controls repetitive failures
Some fantastic facts: Transformer oils last up to thirty years and more.
That definitely means that conducting the right tests at the right time will spare your pockets.