TNB Labs Newsflash

RPVOT(ASTM) vs. Oxidation Stability(IEC): A Comparative Analysis of Insulating Oil Testing Methods

Oxidation stability is a critical property of insulating oils, directly influencing their performance, longevity, and reliability in electrical equipment. Two internationally recognized methods for assessing this property are:

The Importance of Oil Sampling in Lubricant Oil Analysis

Lubricant oil plays a critical role in the performance and longevity of industrial machinery. Whether used in engines, gearboxes, turbines, or hydraulic systems, the condition of the lubricant directly affects equipment reliability. Oil sampling is the first and most crucial step in lubricant analysis, serving as the foundation for accurate diagnostics and maintenance decisions.

Methanol as an Early Ageing Marker in Transformer Insualtion Systems

Transformer insulation systems, particularly those using cellulose-based paper, degrade over time due to thermal, chemical, and electrical stresses. Traditionally, ageing indicators such as carbon monoxide (CO), carbon dioxide (CO₂), and 2-furfural (2FAL) have been used to assess the condition of the insulation. However, these markers have limitations in sensitivity, stability, and reliability especially when the transformer is using thermal upgraded kraft paper (TUP).

Dielectric Dissipation Factor as a Diagnostic Tool for Insulating Oil Degradation in Transformers

Transformers rely on insulating oil for both electrical insulation and thermal management. Over time, the oil degrades due to thermal stress, oxidation and contamination leading to reduced dielectric performance and increased risk of failure. 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.

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.

Oil Reconditioning VS Oil Reclamation

Both insulating oil recondition (Oil Filtration) and reclamation are essential processes for maintaining the performance and longevity of transformer oils, but they serve different purposes and have distinct methods.

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.

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.

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.

Powering Malaysia's Energy Transition with TNBR's BESS Expertise

From land assessment and grid planning to testing, commissioning, and lifetime maintenance, TNBR and TNB Labs offers end-to-end solutions to enhance grid reliability and support renewable energy integration.