Table of Contents
Why is DGA important?
The use of Dissolved Gas Analysis (DGA) as a method for determining the types of pending or occurring faults within power transformers has been in practice for many years. It has been proven that the generation of certain gases within a transformer is an excellent indicator that a failure is pending.
What is DGA test for transformer?
Dissolved gas analysis (DGA) is an examination of electrical transformer oil contaminants. Insulating materials within electrical equipment liberate gases as they slowly break down over time.
What is the purpose of BDV test in transformer?
BDV test means Breakdown Voltage Test. It is done for checking the dielectric strength of the oil of the Transformer. Dielectric strength means the maximum capacity to withstand voltage of insulating oil. This test shows the dielectric strength of Transformer oil.
Why do we check oil in transformer?
Transformer oil, a type of insulating and cooling oil used in transformers and other electrical equipment, needs to be tested periodically to ensure that it is still fit for purpose. This is because it tends to deteriorate over time.
What causes acetylene in transformer oil?
Test results of operational transformer For the transformer, high concentration of acetylene indicates that the transformer has some defects that may induce transformer failure, and low concentration we measured indicates that the transformer is operating in good condition.
Which type of test is known as DGA test in transformer bushing testing?
Dissolved gas-in-oil analysis
Dissolved gas-in-oil analysis, (DGA) The DGA test analyzes the gas concentrations that are dissolved in the transformer oil. Small samples of oil are taken for this test, using a clean, moisture-free container/syringe.
When should I change the oil in my transformer?
Dissolve Gas Analysis of transformer oil should be done annually for 132kv transformer, once in 2 years for the transformer below 132kv transformer, and once in 2 years for the transformer above 132kv transformer.
Why is tan delta important?
The main purpose of the tan delta test is to make sure of maintaining a secure and reliable functioning of the transformer. With the calculation of dissipation factor and capacitance values, it provides the result of insulation behavior of bushings and in windings too.
What is DGA test for transformer oil?
Dissolved Gas Analysis (DGA) tests are performed on the transformer’s cooling and insulating oil. It is of necessity a laboratory test and not a field test. Field testing of transformer oil is usually confined to dielectric strength (spark gap) testing.
What is dissolved gas analysis in transformer oil?
These gases are than dissolved in the transformer oil. If you are interested how these gases are produced and at what temperatures , it is given below at the end of article. Finding out the concentration of various gases in transformer oil is called dissolved gas analysis or gas in oil analysis.
What is the best test for the life of a transformer?
Furan analysis is very sensitive, as damage to a few grams of paper is noticeable in the transformer oil – even in a large transformer. It is a very significant diagnostic test, and bis generally considered the best test for assessing the life of a transformer.
How do you detect abnormal gas in a transformer?
In a transformer, generated gases can be found dissolved in the insulating oil, in the gas blanket above the oil or in gas collecting devices. The detection of an abnormal condition requires an evaluation of the amount of generated gas present and the rate of gas generation.