“Best” is the wrong question — and here is the right one Ask a supplier for the best insulating varnish and you will get a product that is genuinely excellent at something. Whether it is excellent at your job is a separate matter. A varnish that performs beautifully in a vacuum pressure impregnation tank can be useless in… Read More: Best Electrical Insulating Varnish: How to Choose and Specify One »
A bare CTI number can be read wrong. “CTI 400” looks like a clean result until you learn it was run with the aggressive contaminant, or that the 100-drop figure sat 50 V lower, or that erosion ate 3 mm off the specimen while it passed. All of that lives in the report — and a compliant report… Read More: How to Read a CTI and Tracking Test Report »
Insulating material does not have to break down through its bulk to fail. It can fail across its face. A thin film of dirty water, a few hundred volts, and enough time will burn a conductive path into a plastic surface that measured hundreds of megohms when it was clean. That path is called a track. IEC 60112… Read More: Comparative Tracking Index (CTI): IEC 60112 Test Method Explained »
Every motor nameplate, transformer datasheet, and cable spec you read leans on one classification system. Class 155 (F). Class 180 (H). Most engineers use these labels daily without knowing what the numbers really promise — or that the letters are optional. This guide covers the three ways insulating materials are classified: by thermal class, by physical state and… Read More: Classification of Insulating Materials: Thermal Classes Explained »