Home > Classroom

  • Transformer oil analysis - Interfacial Tension The interfacial tension measures the tension at the interface between two liquid (oil and water) which do not mix and is expressed in dyne/cm.The test is sensitive to the presence of oil decay products and soluble polar contaminants from solid insulating materials.Good oil will have an interfacial tension ...
  • Transformer oil analysis - Acidity or Neutralisation Number Acids in the oil originate from oil decomposition/oxidation products. Acids can also come from external sources such as atmospheric contamination.These organic acids are detrimental to the insulation system and can induce corrosion inside the transformer when water is present. An increase in the acidity ...
  • Transformer oil analysis - Dielectric Strength The dielectric strength of an insulating oil is a measure of the oils ability to withsand electrical stress without failure. The test involves appling a AC voltage at a controlled rate to two electrodes immersed in the insulating fluid. The gap is a specified distance. When the current arcs across this ...
  • Transformer oil analysis - Water Content Water, in minute quantities, is harmful in power equipment because it is attracted to the places of greatest electrical stress and this is where it is the most dangerous. Water accelerates the deterioration of both the insulating oil and the paper insulation, liberating more water in the process (heat ...
  • Importance of transformer oil analysis The fault free operation of power transformers is a factor of major economic imporance and safety in power supply utilities and industrial consumers of electricity.In the current economic climate, industries utilities and supply utilities tighten their control on capital spending and make cutbacks in ...
  • Why is water polarity important? The property of polarity helps the water molecules to stick together by a force called cohesion. Polarity also helps water molecules to bind with molecules of other substances through a force called adhesion. You may have observed in your chemistry experiments that water rises up in a tube, that is called ...
  • Why is water polarized? Water molecule is formed by two hydrogen atoms that are covalently bonded with an oxygen atom. In a covalent bond, the electrons are shared equally between the two bonding atoms. But this is not the case with water molecule. In the water molecule, the electron pair is strongly attracted by oxygen than ...
  • Structure of water molecule The structure of water molecule is very simple. A water molecule is made up of one oxygen atom and two hydrogen atoms. The hydrogen atoms are covalently bonded to the oxygen atom by sharing a pair of electrons. The oxygen atom has two unshared electron pairs that makes a total of 4 electron pairs present ...
  • Why does water have a higher surface tension than oil? Water is polar, hydrogen bonds form between water molecules, so it results in higher surface tension. Oil is non-polar, hydrogen bonds does not form between oil molecules, so it leads to lower surface tension.
  • The reasons why oil and water do not mix together When I see drops of oil floating on water, at times, oil comes across as a stubborn liquid, which refuses to mix with water. At other times, I wonder whether it is water, to be blamed for not allowing oil to mix with it. Perhaps, both oil and water do not want to mix with each other or science does not ...