TNB Labs Newsflash
8 Aug 2025
Dielectric Dissipation Factor as a Diagnostic Tool for Insulating Oil Degradation in Transformers
Traditionally oil analysis methods include dissolved gas analysis (DGA), interfacial tension (IFT), and acidity tests. However, the dielectric dissipation factor also known as tan delta or power factor offers direct assess the quality and performance of insulating oils, making it a valuable indicator of insulation health.
11 Jul 2025
Phenolic Resin-Coated Insulating Paper: A Hidden
Hero in High-Voltage Applications
Phenolic resins (PR) are synthetic polymers generally obtained by the reaction of phenol with formaldehyde. Not many transformers user even transformer manufacturer realized that some types of insulating paper used in electrical applications are coated or impregnated with phenolic resin.
16 May 2025
Material Compatibility with Insulating Oil
Insulating oil such as mineral oil, ester oil and silicone oil plays a critical role in the operation of transformer. Using this oil for insulation and cooling must be compatible with various materials within the transformer to ensure reliable operation. This article explores the importance of material compatibility and the effect of incompatibility.
17 Jun 2025
Understanding Corrosive Sulfur in Transformer Oil
Corrosive sulfur refers to certain reactive sulfur compounds in transformer oil that can chemically attack metal components, especially copper and silver. These compounds can form metal sulfides, which are often conductive and can lead to insulation failure. This issue has been recognized for decades, with early reports dating back to 1948.
3 Feb 2025
Ester Oil as an Insulating Fluid :
A Sustainable and Efficient Choice
Ester oils are increasingly being used as insulating fluids in transformers, due to their excellent dielectric properties and environmental benefits. These oils can be either natural or synthetic, with natural esters derived from vegetable oils and synthetic esters produced through chemical processes. Both types offer significant advantages over traditional mineral oils.