Bdv test of transformer oil procedure pdf download

Transformer oil break down voltage bdv cr4 discussion. Nabl accrediated transformer oil testing lab transformer oil test labnabl nabl accredited testing laboratory as per isoiec 17025. In the experiment proper, we considered only the acidity, whose concentration in the transformer oil increases with aging if the transformer, moisture, and a suitable impurity like naohaq. Using a combination of these diagnostic tests allows the oil to. In general, the solubilities and thermal decomposition products of beta fluid are very similar to those from conventional transformer oil. Transformer oil breakdown voltage testing procedure. Before filling oil in transformer through filter machine, it has to be filtered separately in oil tanks and ensure bdv and ppm value. Once power transformer is charged and commissioned, transformer oil. As the name implies, this test analyzes the type and quantity of gases that are dissolved in the transformer oil. Breakdown voltage is measured by observing at what voltage, sparking strands between two electrodes immersed in the oil, separated by a specific gap. Meggers automatic laboratory oil test sets perform accurate breakdown voltage tests on mineral, ester and silicon insulating liquids. Moulded test vessels give repeatable results with lock in precision electrode gap setting adjustment wheels. Testing sequences and procedures are defined by various international standards, many of them set by astm. The significance of the test it will detect free water, dirt and conductive particles.

The electrodynamics processes motivate an evolving ionizing electric. Basics, maintenance, and diagnostics ix contents continued page 6. When transformer is to be filled or topped off in the field, they must be filled under vacuum according to specific instruction. Overheating of the liquid insulation is a slightly different problem in transformers and can be on of transformer oil testing methods. Drums are to be horizontally placed with its opening cap in middle. Transformer oil reservoir must be under positive pressure.

Predicted oil bdv size of testing set samples prediction accuracy 1 96. From my experience, untreated, raw transformer oil has to withstand 40 kv per 2. During oil filling in the main tank of the transformer, it is preferable to connect the inlet hose pipe at the bottom of the tank. The cleaned magnetic stirrer bar as dropped to the vessel so that it is placed at center. Routine testing of transformer oils and insulating oils on a regular schedule is an accepted industry. Requires 1 litre of oil in a polyethylene container. Worlds only true bdv setmeasures hv secondary voltage across oil vessel electrodes, instead of across hv primary. Test parameters transformer oil testing laboratory. For measuring bdv of transformer oil, bdv measuring kit is used. Keeping the requirements of customers in mind, we keep providing latest and the most advantageous products for our customers. During filtration, temperature of oil must remain within 60. Transformer oil testing quick, simple and onsite b2hv.

Now lets move to, transformer oil purification procedure. The mounted electrodes were separated from the container. Transformer spare part and transformer oil bdv test kit. All of these oil types can be tested for dielectric breakdown voltage and tested with megger ots range test sets. Break down voltage test of transformer oil duration. On a regular schedule, it must be subject to an oil test to determine its breakdown voltage the oil test is essential and in most countries even mandatory, since the dielectric oil deteriorates in its isolating and cooling qualities due to ageing and pollution by dust particles or. The insulating material should sustain the voltage up to its dielectric strength. Transformer oil test methods include astm, bs,and other recognized transformer oil analysis testing procedures.

The megger guide to insulating oil dielectric breakdown testing. Testing sequences and procedures are defined by various international. 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. The vessel was cleaned thoroughly and filled with sample oil until the level is about 12mm from the top. All data can be downloaded either as adobe pdf or in text format by email for import into the delta x transformer oil analyst program, or databases such as. The megger guide to insulating oil dielectric breakdown. Adjust the electrode distance inside the oil cup with standard gauge. A new transformer oil shol\uld have at least dielectric strength of 39 kv as per british standards. For measuring bdv of transformer oil, portable bdv measuring kit is generally available at site. The transformer oil is used in the transformer for insulation as well as for cooling purpose. The positive li bdv test was conducted for both oil and developed nfs.

The transformers oil shall be of low viscosity and shall offer the minimum resistance and maximum convective assistance to the flow. Transformer is one of the main asset in the electrical power industry which needs to be maintained for guaranteed uninterrupted power transmission in order to get assured revenue benefits. A low value of bdv indicates presence of moisture content and conducting substances in the 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. Pdf development of an automated break down voltage test set. Peaobdvmxxx automatic oil breakdown voltage tester features available in 100kv m100, 80kv m080 and 60kv m060 versions. Transformer oil used are normally tested using astm d87782 with the kv strength testing,using 1 electrode spaces 0. The megger ots range of dielectric breakdown voltage test sets. The different insulating materials have different dielectric strength.

If the technique of dissolved gas analysis is excluded, oil tests can be divided into two basic groups. To test the oil sample, transformer oil is poured into a porcelain vessel in which two disk electrodes, one of 8mm diameter and one of 25mm diameter, are mounted. Bdv test is an very important testing procedure for the insulation oils in transformer. Bdv tests is used to test the dielectric strength of the transformer. Transformer oil purification filtration processprocedure. Any failure to the transformer can extremely affect the whole functioning of the organization. Pdf significance of transformer oil testing researchgate. 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, 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. A dga test will indicate high thermal gases methane, ethane and ethylene as a result of overheating of the liquid. Parameters of transformer oil the parameters of transformer oil are categorized as, electrical parameters. Lowcost manual instruments are still available, but think.

Insulating oil of transformers and current transformers fulfills the purpose of insulating as well as cooling. The miminum bdv for transformer oil in service is 30kv for 1 minute at an electrode gap of 2. Transformer oil filtration system aditya engineers duration. Connect the earth terminal on the right side of the equipment to the earth wire firmly before start the equipment. Testing consists of measuring breakdown voltage and. 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. Transformer oil breakdown voltage gives an indication about the. They can now be applied to transformers filled with beta fluid. Due to the ultra fast voltage switchoff at flash over transformer oil testing of synthetic oil, ester oil and silicone oil is possible. We have nabl approved transformer oil test laboratory and render our service on short calls as and when required by you with our expert comments and suggestion promptly. The transparent, shielded lid and large test chamber enable easy access to the test vessel.

There are many mineral oil filled transformers that have been in continuous use for more than 50 years. Transformer oil analyst software, the fault condition of the transformer can be diagnosed. Mineral oil is the most common insulating fluid and has been in use since the late 19th century. The oil shall be thin enough to penetrate into narrow ducts and assist in the circulation through transformer winding to prevent local over healing. In this kit, oil is kept in a pot in which one pair of electrodes are fixed with a gap of 2. After filling the oil up to the top of the transformer core, maximum suitable vacuum is maintained above the oil level in the tank to minimize the hazard of bubbles lodging in the inaccessible corners of winding. This test can give an early indication of abnormal behavior of the transformer. Low value of bdv indicates presence of moisture content and conducting substances in the oil. Dissolved gas analysis guide for transformers filled with. In case bdv and ppm values are not achieved within 7 days, check the. Carry out the statutory transformer oil test onsite. Specific transformer oil test method availability will vary depending upon location. To determine dielectric strength, transformer oil is periodically tested by means of an oil punching apparatus.

Astm d1816 standard test method for dielectric breakdown voltage of insulating oils of petroleum origin. The dielectric strength of transformer oil is also known as the breakdown voltage bdv of transformer oil. The bdv of oil in transformer is 60 kv1 min within the gap of 2. The dielectric strength of an oil still ranks as the most common field test. Ots100af, ots80af and ots60af laboratory oil testers. Pdf dielectric strength measurement is the most primitive test which decides the health of. From the experiments, the heating procedures resulted in the production of toxic gases. Various predefined and fully automatic test sequences meet all relevant international standards, thus the models of the ba series fulfill all legal requirements of the mandatory.