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  • General Knowledge of Insulation Oil The main functions of electrical insulation oil are cooling and insulating, also eliminating electric arc when switch off. Because of system leakage, poor sealing, oil in heat-load state for a long time and open storage etc., the water and gas enter into oil which resulting in oil having water gand gas. ...
  • Preliminary judging criteria for transformer oil dissolved gas analysis 1. Nitrogen and around 5% oxygen: Transformer operates normally. 2. Nitrogen and over 5% oxygen: Check tightness of transformer. 3. Nitrogen, carbon monoxide and carbon dioxide: Transformer overload or cellulose is damaged by heat during operation. Operation condition should be checked. 4. Nitrogen and ...
  • Transformer Oil Analysis Transformer Oil AnalysisTransformer oil has several functions. The most important of these are insulation and cooling. In addition, transformer oil gives valuable information about parts conditions in transformers. Therefore, it is necessary to control the quality of transformer oil to monitor transformer. ...
  • Interpretation techniques on DGA results There are several interpretation techniques on transformer oil dissolved gas analyzing results as follows: 1. IEC 60599 Ratios 2. IEEE C67.104, Limits, rates and TDCG 3. Rogers Ratios 4. Kay Gas Method 5. Duval Triangle 6. Trend Analysis 7. New Guidelines for Interpretation of DGA" CIGRE Tast force 15.01.01, ...
  • Causes of fault gases in transformer oil 1. In all types of faults, hydrogen is always present.2. Low energy faults, such as corona partial discharges in gas bubbles, or low temperature hot spots, will form mainly H2 and CH4.3. Faults of higher temperature are necessary to form large quantities of C2H4.4. Faults with a very high energy content, ...
  • Type of gases in transformer oil 1. Hydrocarbons and Hydrogen Methane (CH4) Ethane (C2H6) Ethylene (C2H4) Acetylene (C2H2) Hydrogen (H2) 2. Carbon Oxides Carbon monoxide (CO) Carbon dioxide (CO2) 3. Atmospheric Gases (non-fault gases) Nitrogen (N2) Oxygen (O2)
  • Every DGA starts with the sampling Thousands of litres in a transformer tank, syringe only 40ml., the sample must be as representative as possible.Appropriate sampling techniques are indicated on ASTM D923, IEC 60567 and in many company specifications.
  • 3 Key Steps for DGA There are 3 key steps for transformer oil dissolved gas analysis as follows:1. Oil sample extraction2. Extraction of the gases3. Gases separation & measurement (gas chromatography)
  • Why Dissolved Gas Analysis (DGA) is important? During the last decades, Dissolved Gas Analysis (DGA) has become the most important preventive routine for power transformers. DGA is a simple and non-intrusive oil analysis, that can predict faults via the analysis of the gases generated on the insulating oil. The types of dissolved gases in the oil, ...
  • How the Base affects reaction kinetics of Karl Fischer Titration The type of Base (R'N) and its concentration affect teh overall reaction rate. Traditionally, pyridine was used as the base. However, because of its weak basicity, pyridine can not completely neutralize the alkylsulphurous acid intermediate. As a result, reaction (ROH + SO2 + R'N - [R'NH]SO3R) does not ...