What is a transformer oil tester and how does it work?

A transformer oil tester is an instrument used to assess the quality and condition of insulating oil in power transformers. It works by measuring various parameters such as dielectric strength, moisture content, and dissolved gases. The tester typically employs techniques like capacitance measurement for dielectric strength and gas chromatography for dissolved gas analysis. These assessments help identify potential issues, ensuring the transformer operates efficiently and safely, thereby extending its lifespan.