Schematic view of crude oil distillation base stocks are refined from crude oil to obtain products with the best lubricating properties. What is the bdv value of a 66 kv transformer oil as per is 1866. Because these generate a lot of heat that must be removed, they need to be insulated and they have to resist sparking, the physical and chemical properties of certain oils make them ideal for use in transformers and capacitors. Dec 27, 2019 the transformer oil is used in the transformer for insulation as well as for cooling purpose.
Under federal regulations, used oil is a solid waste managed under 40 cfr 279. Best ways to test transformer oil electrical india. For a high voltage pulse power supply of 140kv amplitude, rise time 1usec, fall. It is intended to use this oil as an electrical insulation and oil as coolant in applications such as transformers, reactors, tap changes, switchgear, oil filled capacitors etc. There is no such thing like bdv break dwon voltage of any transformer. Transformer oil purchase specifications developed under the auspices of the doble oil committee march, 2017 composition this specifications covers new insulating oil for general applications for liquidfilled electrical equipment, which are manufactured from mineral crude, which may be either naphthenic, which has a very low naturally. Transformer lifetime prediction stanford university. A separate oil level gauge is provided for monitoring the oil level in the bushings. The different insulating materials have different dielectric strength. It is used in oilfilled transformers, some types of highvoltage capacitors, fluorescent lamp ballasts north america only, and some types of highvoltage switches and circuit breakers.
Keywords contamination, insulation, testing, classification, significance, inhibited abstract insulating oil used in a transformer is commonly known as transformer oil and it serves many purposes of the transformer by the properties associated with it. Presentation transformer oil free download as powerpoint presentation. Minimum dielectric strength of transformer oil is a wrong question itself, for new insulating transformer oil, the value is 70kv, where as oil in use has values ranging from. These include the chemical and causes of the specific physical properties of the test oils. Oil dissipation factor testing in the field is usually done with the. In on load tap changer, tap position changes, when the transformer is energized either through manual. Transformer testing, transformer oil analysis lab, transformer oil test lab, oil transformer test sl no. Pdf transformer is one of the vital components in power transmission and distribution system. So, the transformer oil primary functions are cooling and insulating the transformer. Transformer oil specifications is 1866 2000frequency of testing property frequency of testing appearance in conjunction with other quantitative tests water content after filling or refilling prior to energizing, then after three and 12 months, subsequently along with dga bdv after filling or refilling prior to energizing, then yearly total. In order to promote public education and public safety, equal justice for all, a better informed citizenry, the rule of law, world trade and world peace, this legal document is hereby made available on a noncommercial basis, as it is the right of all humans to know and speak the laws that govern them. Intelligent energy projects christian osorio, nandan sawant 1. Code of practice for electrical maintenance and supervision of mineral insulating oil in equipment see other formats disclosure to promote the right to information whereas the parliament of india has set out to provide a practical regime of right to information for citizens to secure access to information under the control of public authorities.
Code of practice for electrical maintenance and supervision of mineral insulating oil in equipment etd. Transformer oil also known as insulating oil is a special type of oil which has excellent electrical insulating properties and is stable at high temperatures. 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. Older transformer oil contains pcbs which are extremely toxic get a licensed firm to test the oil for pcbs and. Table 1 recommended limits of unused mineral oil filled in new power transformer clauses 6. Transformer oil break down voltage bdv cr4 discussion. Jul 14, 20 transformer oil specifications is 1866 2000frequency of testing property frequency of testing appearance in conjunction with other quantitative tests water content after filling or refilling prior to energizing, then after three and 12 months, subsequently along with dga bdv after filling or refilling prior to energizing, then yearly total. The transformer oil is used in the transformer for insulation as well as for cooling purpose. Same nine samples were investigated for acidity value by means of titration and also using ph.
What is the minimum value of breakdown voltage of transformer. Failure of a transformer in the chain causes interruption in electricity supply and. Acronyms and abbreviations a air ana selfcooled, nonventilated kw kilowatt ansi american national standards ieee institute of electrical and institute electronic engineers cegb central electric generating mdw moisture by dry weight board mg milligram cfm cubic feet per minute mva megavoltamps ch 4 methane nd not detected c 2 h 2 acetylene n 2 nitrogen. Substation transformer serialnumber samplingdate water kv acidity sub 07 7100tfp353 t259011 17102002 21 48 0.
Transformer oil specifications is18662000frequency of testing. Scribd is the worlds largest social reading and publishing site. The miminum bdv for transformer oil in service is 30kv for 1 minute at an electrode gap of 2. Transformer oil is also known as mineral insulating oil and it serves as liquid insulation in electrical equipment and also dissipates heat of such equipment. For this reason, transformer oil must have some properties like. All winding and core are fully immersed in the oil inside the equipment. The transformer oil also prevents direct contact of atmospherics oxygen to avoid any type of oxidation. 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. If it is found the transformer oil inside the cup comes below the specified level, oil to be top up as per specified level. To determine dielectric strength, transformer oil is periodically tested by means of an oil punching apparatus.
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. Using new insulating oil for recommended limits of unused mineral oil filled in new power transformer. However, in california, used oil is managed as hazardous waste until. Is 1866 oil in service table 1 recommended limits of unused. Failure of a transformer in the chain causes interruption in electricity supply and dislocation of all the. Your test results are well above the mimimum requirement. Generation, transmission, distribution and utilization of electricity. Because these generate a lot of heat that must be removed, they need to be insulated and they have to resist sparking, the physical and chemical properties of certain oils make. Table 1 recommended limits of unused mineral oil filled in new power transformer. If regularly conducted, oil analysis allows identification of specific fault conditions that may be developing. Petroleum oils have been used in electrical equipment since the latter part of the last century. Let us first discuss about the action to be taken on power transformer in monthly basis. The dielectric strength of transformer oil is very important since it is essential in maintaining the reliable operation of power transformers. It refers to the dielectric strength of transformer oil.
The dissipation factor test is widely used as an acceptance and preventive maintenance test for insulating oil. Its functions are to insulate, suppress corona discharge and. Pdf transformer is one of the vital components in power transmission and. Transformer oil or insulating oil is an oil that is stable at high temperatures and has excellent electrical insulating properties. It absorbs the excess amount of heat when the transformer is operational and keeps the transformer cool from inside. Transformer oil is used in oil filled electrical power transformers to insulate, stop arcing and corona discharge, and to dissipate the heat of the transformer i. Power transformer oil testing now if you like this post then please share with your friends and subscribe newsletter to our blog for the daily electrical update. A guide to transformer maintenance fueloil cleaning. While being recycled, used oil is regulated by 40 cfr 279. In addition to a power transformer, this oil is also used in high voltage switches, high voltage capacitors, and circuit breakers. The silica gel breather should be connected to the flange provided and transformer oil should be.
This oil shall also make an important contribution to the efficiency of the solid insulation by penetrating into and filling the spaces. Aug 30, 2019 transformer oil also known as insulating oil is a special type of oil which has excellent electrical insulating properties and is stable at high temperatures. Transformer oil is used in oilfilled electrical power transformers to insulate, stop arcing and corona discharge, and to dissipate the heat of the transformer i. In chapter three and four, an extended discussion on the transformer oil properties is made, taking into consideration the eleven most important ones. The oil valve connecting conservator and transformer tank should be opened and kept in open position. Transformer oil is an important insulation to be monitored periodically to prevent costly damages due to insulation failures in high voltage transformers. It is used in oil filled transformers, some types of highvoltage capacitors, fluorescent lamp ballasts north america only, and some types of highvoltage switches and circuit breakers. For a high voltage pulse power supply of 140kv amplitude, rise time 1usec, fall time 1usec, pulse width 6 usec and prf is 10 hz. Is 1866 oil in service table 1 recommended limits of. Bdv is breakdown voltage value of insulating oil of the transformer. Transformer oil testing by robert turcotte, manager, electrical loss control the hartford steam boiler inspection and insurance company the value of transformer oil testing transformer oil testing is a proven loss prevention technique which should be a part of any conditionbased predictive maintenance program. The dissipation factor of insulating oil equals tangent of delta angle which indicates the dielectric loss of oil and, thus, its dielectric heating. It is therefore, important to keep the transformer oil as free from such contaminates as possible. Much in the same way that a doctor can analyze a patients blood to determine certain health problems, the trained transformer owner can detect problems within the.
From the test results it shall be identified that acidity content is high for degraded oil. This oil shall also make an important contribution to the efficiency of the solid insulation by. Transformer oil is used in the oil filled transformer and in some other system such as high voltage capacitors, fluorescent lamp ballasts, circuit breaker etc. This oil does not communicate with the main transformer oil. Bdv generally refers to breaking down voltage of any dielectric medium such as air. Base stocks generally make up 8095% of a typical engine oil and 5% additives 1.
Basic requirement of transformer oil is that it should be stable at high temperatures w. Transformer oil purchase specification many companies use the doble transformer oil purchase specification tops and the annual oil survey to qualify oil suppliers, using these materials as independent assessments of commercially available oils. If you have a large power transformer that is leaking oil, do not touch it. The oil level in oil cap under silica gel breather must be checked in a onemonth interval. Pdf significance of transformer oil testing researchgate. The key to testing is gaining an accurate evaluation of the test results. What is transformer oil and types of transformer oil an. Standard practices in transformer oil tangent delta. Aug 30, 2017 there is another key point to use transformer oil in a power transformer. A guide to transformer maintenance by stanley myers, joseph kelly and robert parrish transformer maintenance 1. The transformer is a vital apparatus in the electrical equipment in every stage viz. Problem statement the costs of blackouts can be astronomical. Code of practice for electrical maintenance and supervision of mineral insulating oil in equipment.
Test parameters test method ref standard 01 interfacial tension ring method is. Dissolved gas analysis guide for transformers filled with. During this final filteration a seperate degassing column with separate vaccum pump should be used to get better dehydration of oil. The physical properties of an oil depend on its base stock. The life of the transformer is the life of its insulation.
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