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  • Breakdown Voltage Breakdown voltage is a very important factor to transformer oil. Take oil sample from transformer, and put it into the tester. The gap between both electrodes should be 2.5mm. Then, heating, the voltage should be gradually increased. At one value there is a flash takes place, and this value is termed ...
  • What is types of tests needed for transformer oil? Following basic tests are recommended for transformer oil: Dissolved gas analysis, Dielectric breakdown voltage, Moisture, Dielectric dissipation factor, Kinematic viscosity, Surface tension(Interfacial tension), Color, Flash point, Pour point and Acidity.
  • What kind of gas can be measured by DGA? Generally, the following nine dissolved gas in transformer oil can be analyzed: hydrogen(H2), oxygen(O2), nitrogen(N2), carbon monoxide(CO), carbon dioxide(CO2), methane(CH4), ethane(C2H6), ethylene(C2H4) and acetylene(C2H2). When using DGA to measure the dissolved gas in transformer oil, we suggest ...
  • Surface Tension Surface tension, also known as interfacial tension, is a contractive tendency of the surface of a petroleum product that allows it to resisit and external force. Surface tension is used for measuring surface stress.
  • Dissolved Gas Analysis Dissolved gas analysis (DGA) is the study of dissolved gases in insulating fluid such as transformer oil. Insulating materials within transformers and electrical equipment break down to liberate gases within the unit. The distribution of these gases can be related to the type of electrical fault, and ...
  • Kinematic Viscosity Kinematic viscosity is the dynamic viscositydivided by the density (typical units cm2/s, Stokes, St). In practice, it is also an important factor to design and select petroleum product. Capillary viscometer is used to measure flow under gravity at a certain temerature. Till now, the glass tueb viscometer ...
  • Loss Tangent The loss tangent is a parameter of a dielectric material that quantifies its inherent dissipation of electromagnetic energy.
  • Karl Fischer Titration Karl Fischer titration is a classic titration method uses coulometric titration to determine amounts of water in petroleum products. It was invented in 1935 by the German chemist Karl Fischer.
  • Pensky-Martens Closed-cup Method Pensky-Martens closed-cup method is used for measuring the flash point of petroleum products. The brass cup is filled with a petroleum product and covered by a cap. The petroleum product is heated and stirred till to its flash point.
  • Cleveland Open-cup Method Cleveland open-cup method is used for measuring the flash point of petroleum products. It useds Cleveland open-cup apparatus, known as Cleveland open-cup tester. The brass cup is filled to a certain level with a portion of petroleum product. Then, the temperature of this petroleum product is increased ...