If regularly conducted, oil analysis allows identification of specific fault conditions that may be developing. Predicted oil bdv size of testing set samples prediction accuracy 1 96. Transformer testing, transformer oil analysis lab, transformer oil test lab, oil transformer test sl no. Requires 1 litre of oil in a polyethylene container. Degasification, insulating oil, moisture, purification, transformer. Peaobdvmxxx automatic oil breakdown voltage tester features available in 100kv m100, 80kv m080 and 60kv m060 versions. The objective is to get as much of the old oil out as possible. After the transformer oil test is completed, the insulation oil is stirred automatically and the test sequence is performed repeatedly. Sample of bdv test maintenance and repair of medium power transformers. About 80% of these are testing equipment, 6% are other test instruments.
The significance of the test it will detect free water, dirt and conductive particles. Collecting oil sample from oil immersed electrical. Bdv value of transformer oil pdf transformer oil, a type of insulating and cooling oil used in transformers and other electrical typically 5 repetitions, depending on the standard. Oil diagnostic suites for transformer oil diagnostics. Dielectric strength test of transformer oil procedure. For educational purposes only, under proper supervision of laboratory professionals video edited by. Learn what transformer oil is, how to test transformer oil and the different types and properties. If the technique of dissolved gas analysis is excluded, oil tests can be divided into two basic groups. Minimum breakdown voltage of transformer oil or dielectric strength of. Transformer oil test set, oil test set, transformer oil test manufacturer supplier in china, offering portable laboratory 100kv transformer oil breakdown voltage bdv test equipment, infrared forehead thermometer gun high accurate fever body temperature detector, portable sf6 gas purity dew point decomposition comprehensive analyzer kit and so on. In this article, i will discuss transformer oil sample tests other than dissolved gas analysis dga. Based on the procedure above breakdown voltage of an oil sample is determined six. Color d1500 the color of a new oil is generally accepted as an index of the degree of refinement.
Owing to its biradical character, oxygen which has two unpaired electrons in its. The bdv of oil in transformer is 60 kv1 min within the gap of 2. Dielectric strength means the maximum capacity to withstand voltage of insulating oil. Basics, maintenance, and diagnostics ix contents continued page 6. Ageing assessment of transformer insulation through oil test. Adjust the electrode distance inside the oil cup with standard gauge.
There are several methods of interpreting dissolved gas analysis data in transformers filled with beta fluid. Portable laboratory 100kv transformer oil breakdown voltage. Transformer oil used are normally tested using astm d87782 with the kv strength testing,using 1 electrode spaces 0. Bdv tests is used to test the dielectric strength of the transformer. Transformer oil breakdown voltage testing procedure. Due to the ultra fast voltage switchoff at flash over pdf or in text format by email for import into the delta x transformer oil analyst program, or databases such as. Oil to be tested is placed in a cell containing one pair of electrodes placed with a gap of 2. Liquidfilled transformer instruction and maintenance manual. Carry out the statutory transformer oil test onsite. Testing consists of measuring breakdown voltage and other physical and. These include the chemical and causes of the specific physical properties of the test oils. Taking oil sample from power transformers dissolved gases astm d 3612, iec 60567, dissolved water astm d 1533, iec 60814 the following is one of the procedures to collect transformer oil sample. Transformer oil testing and oil analysis transformer oil and other insulating liquids suffer from electrical and mechanical stresses while a transformer is in operation. Connect the earth terminal on the right side of the equipment to the earth wire firmly before start the equipment.
This test can give an early indication of abnormal behavior of the transformer. Transformer oil breakdown voltage gives an indication about the. Srcs transformer assessment package will tell you if. The megger guide to insulating oil dielectric breakdown. Worlds largest database of test records 4,000,000 customer transformer test records. From my experience, untreated, raw transformer oil has to withstand 40 kv per 2. Actual oil bdv predicted oil bdv size of testing set samples prediction accuracy 1 96. Transformer oil testing quick, simple and onsite b2hv. Testing sequences and procedures are defined by various international. Total amount of transformer oil used for analysis in the test apparatus is of 60 ml. Flushing and vacuum of transformer tank shall be performed as per manufacturers recommendations.
Break down voltage is measured by observing at what voltage, sparking strants between two electrodes immerged in the oil, separated by specific gap. Collecting oil sample from oil immersed electrical equipment. Acidity accelerates the oxidation process in the oil. Heating and filtering of insulating transformer oil and filling shall be performed as per manufacturers recommendations. Jul 17, 2017 test the transformer insulation and look for signs of shorts or damaged windings. The different insulating materials have different dielectric strength. Dissolved gas analysis guide for transformers filled with. The megger guide to insulating oil dielectric breakdown testing.
A wide variety of transformer oil tester options are available to you, such as usage, power. The gas space above the oil is filled with nitrogen that could cause asphyxiation or death. From the experiments, the heating procedures resulted in the production of toxic gases. Using a combination of these diagnostic tests allows the oil to. Detects most internal faults, some external faults and some operational errors. Process of collecting oil from oil immersed electrical equipment like transformer. In chapter three and four, an extended discussion on the transformer oil properties is made, taking into consideration the eleven most important ones.
When predictive maintenance transformer and oil tests has disclosed a serious problem of moisture, combustible gas andor oil decay products, and on site purification is the chosen procedure the following steps are suggested. Gray transformer chemistry services introduction the fault free operation of power transformers is a factor of major economic importance and safety in power supply utilities and industrial consumers of electricity. Remove a sample of insulating transformer oil in accordance with astm d923. Evaluation of transformer condition using individual and tdcg concentrations.
We collect oil sample for performing different tests on the oil to determine different physical, chemical and electrical characteristics of the oil. Transformer oil bdv tester made in china transformer oil. Transformer oil testing transformer testing california. Lowcost manual instruments are still available, but think. No characteristics requirements method of test 1 appearance the oil shall be clear and transparent and free from. Due to the ultra fast voltage switchoff at flash over transformer liquidfilled transformer instruction and maintenance manual 3 4 internal inspection note. The gap of the electrodes is first checked with a gauge. Liquidfilled transformer instruction and maintenance. The transformer oil testing device measures and reports the root mean square value of the breakdown voltage. After a transformer has been received at its final destination, it is advisable to put it full of oil on its permanent place, even if it is not going to be placed in operation immediately.
A new transformer oil shol\uld have at least dielectric strength of 39 kv as per british standards. Transformer oil test parameters for ageing assessment 28, 80. During the transformer operation for a period, insulation oils will become dirty degradation which results in loosing function of the oil in transformer as insulation and cooling, in that case, transformer will face some serious problems. The oil in the test cell shall be at least 40 mm above the electrodes and it should be allowed to stand for 20 minutes before performing the test to let air bubble escape. Manufacturer of transformer testing oil bdv test kit, winding resistance meter, transformer turn ratio tester offered by beacon energy solutions private limited, gurgaon, haryana. Collect the oil sample of transformer oil from the bottom valve of the transformer.
Testing sequences and procedures are defined by various international standards, many of them set by astm. The insulating material should sustain the voltage up to its dielectric strength. When customer used these standard like rogers, gas ratio, gas levels ieee c57. We should always take at least 1 to 2 liter of oil from bottom valve or oil sample valve if available depending upon the tests to be performed on that sample. Transformer oil breakdown voltage bdv test youtube. Replace the transformer drain plug and refill the unit with fire. Transformer oil reservoir must be under positive pressure. Dissolved gasinoil analysis the most important test that can be done on the liquid insulation of a transformer is an annual dissolved gas analysis dga. The standard test suites are designed for individual samples to deliver a routine set of oil analysis at low cost. Transformer testing oil bdv test kit manufacturer from gurgaon. China portable laboratory 100kv transformer oil breakdown. If this is not possible, the transformer has to be placed in a dry place and the transformer must be filled with oil. As the name implies, this test analyzes the type and quantity of gases that are dissolved in the transformer oil. It is done for checking the dielectric strength of the oil of the transformer.
The automatically generated test reports are provided in pdfformat and are stored on a usb stick. Sep 24, 2017 with the help of transformer oil testing kit we can test transformer oil learn the process step by step. For oils in service, an increasing or high color number is an indication of contamination, deterioration, or both. Any equation to find the theoretical bdv of transformer oil. Test parameters test method ref standard 01 interfacial tension ring method is. Keep the oil pot in open air for 5 minutes so that air bubble if any gets out. The various combinations of samples ideal sample along with natural dust and saw dust are evaluated for flash point and fire point values in the closed cup are shown in table 2. As a result the breakdown voltage is calculated as mean value of the individual measurements. The transformer oil is used in the transformer for insulation as well as for cooling purpose.
The above standard testing is offered in specific diagnostic suites designed to provide the maximum condition information on the transformers. Bdv test is an very important testing procedure for the insulation oils in transformer. This test shows the dielectric strength of transformer oil. Mineral oil is the most common insulating fluid and has been in use since the late 19th century. In this paper, we will study about the transformer oil filtration machine and how it purifies the contaminated transformer oil. Once the oil is drained, proceed with flushing out the inside of the transformer. The dielectric strength of an oil still ranks as the most common field test. The following are the methods that are recommended by dielectric systems, inc. For veryfication of oil purity every year to be checked the bdvbreakdown voltage,we have take out the transformer oil in the transformer and collect in the high voltage kit inthe kit two stem will be there within the 2mm gap and then apply the high. If everything checks out, drain the transformer oil. Method of test for interfacial tension of oil against water. Low value of bdv indicates presence of moisture content and conducting substances in the oil. Dec 15, 2016 for educational purposes only, under proper supervision of laboratory professionals video edited by. An internal inspection is necessary only if internal damage is suspected because of external indications of rough handling.
In addition there are contaminations caused due to chemical interactions with windings and other solid insulations, catalyzed by. Testing consists of measuring breakdown voltage and. Transformer oil analysis basic introduction by n robinson, wearcheck as blood tests disclose ones state of health, so oil analyses disclose the condition of a 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. The normal procedures of collecting oil from a transformer or other oil immersed electrical equipment are given in following points. Gases generate by degradation of fluid or cellulose. Round robin test 0 100 200 300 400 500 600 700 800 900 0 20 40 60 80 100 120. Worlds only true bdv setmeasures hv secondary voltage across oil vessel electrodes, instead of across hv primary. The megger ots range of dielectric breakdown voltage test sets. Maintenance and repair of medium power transformers. Worlds leading reclaimer of transformer oil over 1 billion gallons processed. The gas space above the oil is filled with nitrogen.
A wide variety of transformer oil tester options are. Dielectric strength of transformer oil is also known as breakdown voltage of transformer oil or bdv of transformer oil. Dissolved gasin oil analysis the most important test that can be done on the liquid insulation of a transformer is an annual dissolved gas analysis dga. What is the minimum value of breakdown voltage of transformer.
For measuring bdv of transformer oil, bdv measuring kit is used. Only competent and qualified should open a sealed transformer. Pdf significance of transformer oil testing researchgate. If oil becomes acidic, water content in the oil becomes more soluble to. Test the transformer insulation and look for signs of shorts or damaged windings.
1111 1623 193 915 300 607 254 610 390 553 1193 1071 253 449 1019 829 96 1387 855 506 664 1135 744 415 1272 951 1248 635 258 1005 39 84 861 747