The things which is separate between Dissolve Gas Analysis(DGA) with Mineral Oil & with Beta Fluid.
Gas Solubility:
generated key gas and what kind of insulation is involved. 
There are a number of techniques to identify those gases. But the most famous ,reliable and effective method is DGA .In this method first of all we sampling the oil then test these samples to measure the amount of concentration of dissolved gases. It is important to perform DGA of transformer every year and the other important is relate previous results and this will help to predict the problems in the transformer.
General Theory of Gas Generation
Electrical disturbance and Thermal decomposition are the two basis principal that causes the formation of gases in the operating transformer. There is no required high temperature to produce the gases but the gases generate at normal operating temperature .hydrocarbon molecule are the basic part of mineral oil in the transformer. The decomposition of these molecules is very complex in the thermal or electrical. This figure describe the types of thermal and electrical faults.
When chemical reaction take place carbon hydrogen and carbon-carbon bonds break. The fragments of hydrocarbon and hydrogen atom are formed. At the end these fragments attach to each other and formed different gases like hydrogen(H2), methane(CH4),acetylene(C2H2),ethylene(C2H4) and ethane (C2H6).Electric faults (thermal decomposition) generate different gases like carbon mono oxide(CO2),methane(CH4), monoxide (CO), hydrogen (H2) when the cellulose insulation involved in it. These gases are known as the key gasses.
There is problem to exceed the concentration level in the transformer so we should apply differ method to determining the seriously problems with in transformer. When we use these techniques the results of these key gases ratio compere with the suggest limits.
Gas Solubility:
In the given below table it is shown that the solubility of different gases in beta fluid is approximately is same as the conventional transformer oil. It is usually seen that the difference between two fluids is less than 10 percent, which is often due to some poor analysis method and error in the extraction. Now the actually mean is that we can apply same techniques because the gases generated in the transformer oil also solved in the beta fluid at the same extent as that they are in mineral oil. To find the problem it is necessary to find the rate of generated gas and the total amount of key gas present in the transformer. If we find the composition of generated gas then we easily find the source of
generated key gas and what kind of insulation is involved.
There are a number of techniques to identify those gases. But the most famous ,reliable and effective method is DGA .In this method first of all we sampling the oil then test these samples to measure the amount of concentration of dissolved gases. It is important to perform DGA of transformer every year and the other important is relate previous results and this will help to predict the problems in the transformer.
ASTM D3613, ASTM D3612, and ANSI/IEEE C57.104, respectively are the standards associate with sampling, testing, and analyzing the results. In this report we analyze the DGA data from field transformers and discuss the method to analyze the faults.
General Theory of Gas Generation
Electrical disturbance and Thermal decomposition are the two basis principal that causes the formation of gases in the operating transformer. There is no required high temperature to produce the gases but the gases generate at normal operating temperature .hydrocarbon molecule are the basic part of mineral oil in the transformer. The decomposition of these molecules is very complex in the thermal or electrical. This figure describe the types of thermal and electrical faults.
When chemical reaction take place carbon hydrogen and carbon-carbon bonds break. The fragments of hydrocarbon and hydrogen atom are formed. At the end these fragments attach to each other and formed different gases like hydrogen(H2), methane(CH4),acetylene(C2H2),ethylene(C2H4) and ethane (C2H6).Electric faults (thermal decomposition) generate different gases like carbon mono oxide(CO2),methane(CH4), monoxide (CO), hydrogen (H2) when the cellulose insulation involved in it. These gases are known as the key gasses.
The key gasses are generally assume the combustible (Carbon dioxide is not combustible).If the key gasses are combustible which is present in the transformer indicate the warmly that thermal, electrical or corona faults are exist.
The amount of key gases produce is directly proportional to the temperature and how much amount of material is present at that temperature and the gases produce at the moderate temperature will produces same volume at high temperature. So that the concentration of each gas which is present in the transformer mineral oils used as it and also used to predict the faults in the transformer. The concentration level of each gas (in ppm) is taken after analyze the sample and evaluating the result of DGA.
Its very important that any speedily increase in the concentration of key gases is the indication of some major problem in the transformer. Whenever DGA result shown exceed the key gas concentration level and the normal limits are also increase, then it is favorable to take another sample and analyze that one. After analyze the result compere both of these results which is taken before and after. Now look really concentration increase. The given table is derive ANSI/IEEE C57.104 information. The concretion level of different gases is given in the table.
There is problem to exceed the concentration level in the transformer so we should apply differ method to determining the seriously problems with in transformer. When we use these techniques the results of these key gases ratio compere with the suggest limits.
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