Interfacial Tension (IFT)
ASTM D-971 Interfacial Tension of Oil against Water by Ring Method IFT is a fluid test used to determine the presence of oxidation by-products, polar contaminants, and other decomposition products. These can be acids, oxidation intermediate compounds, varnishes, and other fluids that are in the fluid. These compounds generally lower the IFT value, and that […]
Dielectric Breakdown Method Differences
Transformer insulating fluid acts as an insulator for electric and thermal capacities for many electrical equipment. Measurement of dielectric breakdown is a major way to measure the capability of a fluid to withstand electrical stress. In measuring dielectric breakdown, an increasingly high voltage is applied across the fluid via electrodes. The breakdown occurs when the […]
Significance of Testing for Specific Gravity
Specific Gravity or relative density is a measure of the density of transformer fluids relative to water, being scaled at 1.000. The value from testing is normalized to 15C/15C. With the introduction of different transformer insulating fluids such as Natural and Synthetic fluids, specific gravity testing can be key in a quick determination of fluid […]
Destruction of Dibenzyl Disulfide in Transformer Oil
ABSTRACT Dibenzyl Disulfide (DBDS) is one of several sulfur compounds known to cause copper corrosion in transformers under certain circumstances. Remedial processes such as adsorbents, absorbents, and oil change-out have been known to reduce the concentration of DBDS in the oil. However, if not destroyed or removed below several mg/kg (ppm), the breakdown of the […]
What is DGA Testing?
Dissolved Gas Analysis, or DGA Testing, is one of the sharpest sticks in the tool bag of analyses used in a predictive/preventative maintenance plan by transformer oil testing. The insulating fluids used in transformers and related equipment are used because of their high dielectric strength and chemical stability. However, conditions and faults within the equipment […]
Methodologies for PCB Analysis of Transformer Oil
Before their manufacture was banned in 1979, PCBs were used widely in electrical equipment, including transformers and fluorescent light ballasts. Many transformers still contain traces of PCB-contaminated oil even after the oil has been changed several times. Because of Federal and State regulations, PCB content is frequently required when servicing or disposing of electrical equipment containing […]
Maintaining Transformer Oil Through Hot Oil Reclamation
Maintaining transformers is not a new idea, but funding for transformer maintenance services continues to decline. The accounting structure incentivizes the purchase of new transformers. Globally, demand for new transformers has lead times extending up to three years. Unless there are enough spare transformers in inventory, it only makes sense to have a robust maintenance […]
What’s Happening Inside Your Transformer?
Mineral oil is the lifeblood of a transformer and is by far the dominant fluid used in transformers. There are many reasons why mineral oil is used as an insulating fluid in transformers. One, it is an excellent dielectric medium for insulating the components within the transformer, and two; it is a good heat transferring […]
