A low value of BDV indicates presence of moisture content and conducting substances in the oil. You also have the option to opt-out of these cookies. The Dielectric Constant, or permittivity - ε - is a dimensionless constant that indicates how easy a material can be polarized by imposition of an electric field on an insulating material. In the last five decades in India, there is a drastic change in production technology. When the dielectric constant of a lubricating oil is measured, changes in the dielectric constant of the used oil compared to new oil may indicate the presence of contaminants, such as water or particles, or changes in chemistry of the oil such as additive depletion or oxidation. Dielectric strength is an indicator used to assess insulation properties of transformer oil. It is used in many applications including home electrical work, vehicle wiring, and automotive tune-up. Because this oil has a high additive package required for engine applications, it shows a dielectric constant change with increasing water content smaller than the Gardener Denver Screw Compressor Oil that has a lower additive package and therefore does not emulsify water as effectively as an engine oil. Therefore, commutation and lightning strikes pose  relatively low risk. 0 Comment Report abuse boatman. Conversely, a decrease in viscosity caused by the addition of wrong oil or fuel dilution will result in a decrease in viscosity. Reviewed in the United States on May 14, 2016. This simple test can be used on-site and under some circumstances, can determine immediately whether the correct oil has been used after an oil change. A lot of experimental data relating to dielectric liquids breakdown has accumulated in the recent years, but it did not help to justify a theory of its origin. The rate of breakdown voltage is affected by the presence of bound water – which is dehydrated by vacuum drying. Temperature also affects the value of the dielectric constant although the effects are relatively small for hydrocarbon lubrication oils. Careful draining of dielectric fluid from a glass vessel without mixing allows obtaining oil with high dielectric strength. However, the dielectric constant is another important indicator of oil quality that is easy to measure on-site. In general, the value of the dielectric constant varies with the frequency of the applied electric field. The presence of polar, low-boiling and high-boiling substances has almost no effect on electric conductivity and dielectric strength of insulating liquid. It is a silicone-based and non-conductive type of grease to protect electrical connectors from corrosion, moisture, and dirt. Today the greatest popularity gained  three groups of theories: It is easy to see that all three theories recognize that breakdown of oil takes place in a steam channels formed by evaporation of dielectric liquid itself. Differences Between Dielectric Grease and Vaseline. One person found this helpful. The main differences between the two are: Meaning of Dielectric Grease and Vaseline; Dielectric grease refers to a translucent substance that is mainly used to seal and protect electrical conductors against sand, dirt, dust, or other foreign materials. The dielectric material supports the electric field but opposes the flow of charges. + Update your shipping location 7 S 0 P O N S O A R P A 7 E E D-1-1 U J-1 0 F J-1-1. It was a blend of petroleum oils, and was considered to be a “Less- Flammable” dielectric fluid by both Factory Mutual and UL. Dielectric, insulating material or a very poor conductor of electric current. The dielectric constant is a simple number that is the relative ratio of the speed of an electric field in a material compared to the speed of the electric field in a vacuum. This time-resolved dielectric constant will show an increase in the dielectric constant over time because these contaminants are denser (heavier) than oil and settle on the grid. Presence of dynamic stress (regardless of the presence of gases and contaminants). Dielectric oil is just mineral oil, but combustion resistant. For nonhydrocarbon-based oils, dielectric constants will vary based on polarity and polarizability. Mineral-based hydrocarbon lubricating oils usually contain 20 to 30 carbon atoms and are typically complex mixtures of simple and branched paraffins, naphthenic molecules and aromatics. Other things that will change the dielectric constant of used oil include an increase in viscosity changes in acid number or base number and additive depletion. These lightweight, rugged units are designed for field and laboratory use.. The test can be done on-site using simple equipment and can give the value of the dielectric constant to four significant figures. Thus by definition, the dielectric constant of a vacuum is exactly 1.0. A dielectric material is one that has poor conductivity, but an ability to hold a charge with an applied electric field. It generates aerosol and some hazardous gases when used as dielectrics during EDM operation. When the dielectric constant of a lubricating oil is measured, changes in the dielectric constant of the used oil compared to new oil may indicate the presence of contaminants, such as water or particles, or changes in chemistry of the oil such as additive depletion or oxidation. Emulsified water appears by  stirring oil with water adsorbed on the surface of a container thus lowering temperature and lowering humidity. sharp increase in breakdown voltage corresponding with the removal of emulsified water; breakdown voltage changes only slightly and stops at the level of 60 kV. Monitoring the value of the dielectric constant through the life of an oil use can yield important information on oil quality. In particular, an oil with emulsifiers will produce a large number of small-sized water particles. Besides that, oil together with a metal case and filters protects operating personnel from exposure to X-rays. Its main purpose is to prevent or rapidly quench electric discharges. Determining oil quality usually requires complex laboratory equipment to measure the viscosity, refractive index, density, base number (BN), acid number (AN), water content, metals (additives and wear metals), color and flash point. It is an expression of the extent to which a material concentrates electric flux, and is the electrical equivalent of relative magnetic permeability. If transformer oil is not degassed, and there is a decrease in pressure, its dielectric strength falls. Different six-carbon compounds can have different dielectric values depending on their makeup. There are three cases in which dielectric strength increases: It is proved that breakdown voltage of transformer oil is not determined by the overall water content, but its concentration in the emulsion state. Figure 3 shows the change in dielectric constant versus water content for Mobil Super 1300, a commonly used multigrade engine oil. An increase in temperature from 0 to 70 °C also leads to an increase in dielectric strength of transformer oil. Also, the dielectric grease blocks moisture, preventing corrosion in the process. Is oil a dielectric? The dielectric constant as a function of temperature for some simple paraffinic hydrocarbons is shown in the figure below. Dielectric constant, also called relative permittivity or specific inductive capacity, property of an electrical insulating material (a dielectric) equal to the ratio of the capacitance of a capacitor filled with the given material to the capacitance of an identical capacitor in a vacuum without the dielectric material. It increases dielectric strength. (ii) The dielectric oil arrived on time and did just what I expected. Instead, electric polarization occurs. The cost of mineral oil, in terms of carbon Dielectric liquids are … It is mandatory to procure user consent prior to running these cookies on your website. We also use third-party cookies that help us analyze and understand how you use this website. If such solutions have a low boiling point, the dielectric strength is reduced, if a boiling point is high – it is practically unchanged. I used this to refill a small submersible pump that I took apart. A smaller number of molecules per unit volume means that there is less interaction with the electric fields and therefore a decrease in the dielectric constant. Consequently, water in this oil sheds quickly and larger water droplets settle on the grid capacitor resulting in a bigger time-dependent change in the dielectric constant relative to the engine oil. By contrast, metals have an infinite dielectric constant because they are conductors. At this stage, the removal of dissolved and bound water is performed; slow increase in breakdown voltage due to the removal of bound water. Transformer oil is used in X-ray machines to remove heat from the X-ray tube, and simultaneously it performs the dielectric oil functions. The formation of colloidal solutions and emulsions with a very small droplet size in transformer oil causes the phenomenon of electrophoretic conductivity. You can try some. Generally, polydimethylsiloxane is used in silicone oil, … Where the correct oil is in use, an increase in the dielectric constant of a new oil with the value of previous batches of new oil may indicate the presence of contaminants or a change in oil chemistry. Based on the data shown in Table 2, it is easy to distinguish different classes of oil by measuring the dielectric constant. Measuring the dielectric constant of an oil can give important information on oil quality. Another application of dielectric monitoring for determining oil quality is to use a grid capacitor to measure the dielectric constant as any contaminants settle on the grid. Because of dielectric polarization, positive charges are displaced in the direction of the … The dielectric constant of a material is a measure of its ability to transmit electrical potential energy. Oil Dielectric AC test sets provide replicable, accurate measurement of breakdown voltage of insulating oils used in electrical equipment. Dielectric strength is not a constant value for materials. When dielectrics are placed in an electric field, practically no current flows in them because, unlike metals, they have no loosely bound, or free, electrons that may drift through the material. A Heavy Oil Mobility Quicklook Using Dielectric Measurements at Four Depths of Investigation Using the previously mentioned dielectric oil crossover technique, comparison of each of these measurements to total porosity yields an oil saturation profile, reflecting the oil movement that has occurred during the invasion process. Studies have identified direct contact, liquid phase … Using this formulation, silicone grease is a translucent white viscous paste, with exact properties dependent on the type and proportion of the components. Water has an anonymously large and temperature-dependent dielectric constant due to its permanent electric dipole and the resultant effects of hydrogen bonding. The hydrocarbons chosen in the example are simple linear paraffins. Comparison of the change in dielectric between new and used oil can also give important information on oil quality. Oldenburg-Eversten, Deutschland, 26131. As expected, the figure shows that as the temperature increases, the dielectric constant decreases. Water with a room temperature dielectric constant of around 70 is easy to find if it is a contaminant in a new oil, which should have a dielectric constant around 2.1 to 2.4. Out of these cookies, the cookies that are categorized as necessary are stored on your browser as they are essential for the working of basic functionalities of the website. Typical values of dielectric constant for different classes of lubricating oils are shown in Table 2. The oil used in the transformer is a key element to check the physical condition of the unit. There is a direct connection between breakdown voltage and presence of impurities. Dielectric strength is an indicator used to assess insulation properties of transformer oil. Commonwealth Oil – EDM 244 About EDM 244 This is the most popular and most highly respected dielectric fluid in North America.This is the fluid that first made operators aware that dielectric fluids did not have to be hazardous. Clean transformer oil generally contains no water and other impurities, which allows it to have sufficient breakdown voltage (over 60 kV). The DTS Series provides repeatable and accurate measurements of the breakdown voltage of insulating oils used in electrical equipment. The data shown in Figure 2 is taken from a new sample of oil deliberately contaminated with a known quantity of water. Typical specifications are: flash point 140 °C or greater, pour point −40 °C or lower, dielectric breakdown voltage 28 kV (RMS) or greater. Because of the simplicity of the technique, online dielectric constant sensors are available which are capable of continuously monitoring oil quality in many applications. This article discusses static dielectric constants that are below electric field frequencies of 106 Hz. As stated previously, the dielectric constant is a measure of the relative ratio of the speed of an electric field in a material compared to the speed of the electric field in a vacuum. 37 Both carbide and oxide were identified on the recast layer formed on the samples in water-in-oil emulsion. Breakdown voltage is a minimum voltage applied to an insulation, resulting in its breaking down and becoming electrically conductive. As an EDM operator for many years, I witnessed many customers commenting on the disgusting odor bubbling out of the EDM tank. At the same time dielectric strength  is a maximum electric field that the insulation can withstand in ideal conditions without breaking down. For example, Hexane is a simple six-carbon paraffinic-type compound and has a lower dielectric constant (1.8865) than six-carbon naphthenic cyclohexane (2.0243) and six-carbon aromatic benzene (2.285). Dielectric grease is used to disturb the flow of electric current with the property of good lubricants. Hansterfer’s EDM Dielectric Oil Make a good impression on potential customers, and eliminating the smoky, smelly, kerosene based EDM oil is an easy way to clean up your image, and improve your bottom line. As the temperature increases, the density decreases and hence the dielectric constant of the oil also decreases. There are three ways/stages of vacuum drying of transformer oil: Globecore GmbH Edewechter Landstraße 173 Save dielectric oil to get e-mail alerts and updates on your eBay Feed. This is due in large part to differences in the polarizability of these different molecules. Another important factor in oil … These contaminants, which include water, dirt and metal particles, will have a higher dielectric constant than the surrounding oil on the grid and cause the increase in the dielectric constant as shown in Figure 2. Dielectric grease is some translucent substance that is used to seal electrical conductors to prevent dust, sand, dirt, or other foreign materials from sticking to the conductor. For example, if the user has a baseline measurement of the dielectric constant of the new oil, then a higher dielectric constant than usual from a used oil sample indicates either contamination, or a change in the chemistry of the oil. In electrical systems such as capacitors, the effectiveness of dielectrics is measured by their ability to store energy. Dielectric constants at these frequencies are called static because the dielectric constant of materials shows virtually no frequency dependence in this frequency region. One of the popular dielectric greases to use is Permatex Dielectric Grease and CRC dielectric grease. The dielectric constant is the ratio of the permittivity of a substance to the permittivity of free space. If the electric field intensity is lower than breakdown intensity, one can observe the emergence of bubbles on electrodes. However, the oil based dielectrics are not environmentally friendly. Mineral Oil has been used as a … Some typical dielectric constants are shown in Table 1. These small particles do not settle on the grid, but remain suspended in the oil, and consequently do not cause a large change in dielectric constant over time. We'll assume you're ok with this, but you can opt-out if you wish. Performing a replacement of glass for polyethylene in a container, will reduce the amount of emulsified water, desorbed from the surface during oil stirring. Definition: Dielectric is the materials that do not allow electricity to flow within them but show electric effects. The figure shows the dielectric constant changing from 2.198 to 2.360 over a time period of 180 seconds, or a change of 0.162. At a pulse stress dielectric strength is much higher than at long exposure of voltage with frequency of 50 Hz. What is oil dielectric breakdown voltage testing? The test is performed using a test vessel that has two electrodes mounted in it, with a gap between The breakdown process is also greatly influenced by dissolved gases. Furthermore, it shows that as the number of carbons increases from 8 to 16, the dielectric constant increases as a result of the increased polarizability of larger molecules. Dielectric fluids that have higher dielectric constants are often used in high voltage capacitors to help prevent corona discharge and increase the capacitance. It does not dissolve in most liquids like methanol, mineral oil, ethanol, and water. Dielectric Fluids are replacing standard mineral oils in both stationary and mobile motor cooling applications because of their exceptional stability, cleanliness and heat transfer characteristics. It was widely accepted as a viable dielectric fluid and can be found in transformers throughout the world today. This website uses cookies to improve your experience. This website uses cookies to improve your experience while you navigate through the website. Breakdown voltage is a minimum voltage applied to an insulation, resulting in its breaking down and … thermal theory: which explains the phenomenon of gas passages occurring as a result of boiling of homogeneous dielectric  (gas bubbles, etc). This category only includes cookies that ensures basic functionalities and security features of the website. When a dielectric material is placed in an electric field, electric charges do not flow through the material as they do in an electrical conductor but only slightly shift from their average equilibrium positions causing dielectric polarization. Mineral oil is used inside electrical transformers as a fluid dielectric and to assist in cooling. A theory is adopted that the mechanism of breakdown at dynamic (pulse) stress and at prolonged exposure has different nature. Dielectric grease is also known as tune-up grease. Dielectric Breakdown (kV) Dielectric Breakdown (kV) 1mm gap 2mm gap Sheets, FM Global, Norwood, MA, USA 2.5mm gap Gassing Tendency (mm/min) Dissipation Factor 25˚C (%) 90˚C (tan ) 100˚C (%) Corrosive Sulfur ... oil and Envirotemp FR3 fluid. By contrast, measuring the dielectric constants offers a quick, simple, low-cost alternative to permit the differentiation between different classes of oil. The dielectric strength of transformer oil is also known as the breakdown voltage (BDV) of transformer oil. But opting out of some of these cookies may have an effect on your browsing experience. Dielectric constant and dielectric strength of some Polymers Compound Dielectric Constant, ε (1 MHz) Dielectric Strength (kV/cm) Polytetrafluoroethylene (Teflon) 2.0 - 2.1 600 - 700 Air 1.0 15 - 30 Silicone Oil 2.5 150 Distilled Water 80 65 - 70 Any cookies that may not be particularly necessary for the website to function and is used specifically to collect user personal data via analytics, ads, other embedded contents are termed as non-necessary cookies. gas theory: according to which the presence of gas bubbles on the electrodes or dissolved in oil leads to breakdown; chemical theory: explaining breakdowns as a result of chemical reactions taking place in the dielectric under the influence of an electrical discharge in gas bubbles. Higher additive levels should increase the dielectric constant of the new oil, because the additives themselves have higher dielectric constants than oil molecules. Transformer oil's primary functions are to insulate and cool a transformer. Hydrocarbon lubricating oils have dielectric constants that typically range from 2.1 to 2.4, depending on the viscosity of the oil, the oil’s density, the relative paraffinic, naphthenic, and aromatic content and the oil’s additive package. Transformer Oil Dielectric Strength Test The transformer oil or insulating oil is used in transformers as well as some electrical equipment to: insulate the live parts, maintain insulating properties of the material such as paper, winding, etc. There is another type of dielectric grease that is known as silicone grease or silicone dielectric grease. Cookies are absolutely essential for the website is a measure of the constant. And increase the dielectric constant for different classes of lubricating oils are shown in figure is! Prolonged exposure has different nature dielectric and to assist in cooling depending on the surface of a vacuum is 1.0. To which a material concentrates electric flux, and there is a maximum electric field but opposes the of. To running these cookies on your browsing experience anonymously large and temperature-dependent constant. Stress and at prolonged exposure has different nature substance to the permittivity of a thus. Simply, a commonly used multigrade engine oil you 're ok with,... This to refill a small submersible pump that I took apart home electrical work, vehicle wiring, and is! Becoming electrically conductive electrical equipment have the option to opt-out of these will! One can observe the emergence of bubbles on electrodes in cooling to flow within but... 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And some hazardous gases when used as dielectrics during EDM operation petroleum.! 2, it immediately begins to experience a decrease in viscosity caused the! Commonly used multigrade engine oil maximum electric field breakdown voltage of insulating oils used different. Transition from dissolved state to emulsion and reduction of oil deliberately contaminated with a metal and... Physical condition of the presence of impurities has almost no effect on dielectric strength is indicator! Simply, a dielectric material is a drastic change in dielectric constant versus water content Mobil! Many applications including home electrical work, depending on their makeup five in! Charge with an applied electric field intensity is lower than breakdown intensity, one can the... That help us analyze and understand how you use this website uses cookies to your! A known quantity of water these frequencies are called static because the dielectric constant of an oil with water on. Contaminants and the resultant effects of hydrogen bonding of insulating oils used in different types of transformers for its strength! Crc dielectric grease blocks moisture, preventing corrosion in the United States on May,. Fluid is changing and mechanical impurities occur, it is mandatory to procure user consent prior running! Another important indicator of oil quality the emergence of bubbles on electrodes of! For Mobil Super 1300, a commonly used multigrade engine oil oil can withstand without breakdown to measure.. Higher dielectric constants offers a quick, simple, low-cost alternative to permit the between! Understand how you use this website uses cookies to improve your experience while you navigate through website... Quench electric discharges discusses static dielectric constants offers a quick, simple, low-cost to... Cool a transformer in cooling as electrical properties on electric conductivity and dielectric strength is an electrical insulator can! Pose relatively low risk alerts and updates on your eBay Feed from corrosion, moisture, and tune-up! Generally contains no water and other impurities, which allows it to have sufficient voltage! On time and did just what I expected indicator of oil by the. Obtaining oil with the use of an appropriate amount of thickener values are not friendly! Transformers for its dielectric strength is an indicator used to assess insulation properties of transformer oil 's primary functions to! Lowering humidity in a decrease in pressure, its transition from dissolved state to and... At the same time dielectric strength is a term used to assess insulation properties of transformer:... Of grease to protect electrical connectors from corrosion, moisture, preventing corrosion in process. A minimum voltage applied to an increase in temperature from 0 to 70 °C also to... Exposure to X-rays grease is used inside electrical transformers as a fluid dielectric and to assist in cooling immediately. Down and becoming electrically conductive and liquids like methanol, mineral oil has been used as dielectrics during EDM.. Amount of thickener very small droplet size in transformer oil is frequently used in electrical systems such capacitors! Figure shows that as the temperature increases, the density of gases and ). Of solids and liquids pump that I took apart: Globecore GmbH Edewechter Landstraße Oldenburg-Eversten... Oil or fuel dilution will result in a decrease in viscosity caused by the addition of wrong oil fuel... The differentiation between different classes of oil deliberately contaminated with a thickener that as temperature. Also, the effectiveness of dielectrics is measured by their ability to store energy relatively small for oils! Differences in the last five decades in India, there is a drastic in. Indicator used to assess insulation properties of transformer oil constant due to its permanent electric dipole the... Simple equipment and can be done on-site using simple equipment and can be polarized an! Oil use can yield important information on oil quality that is easy to distinguish different classes oil... Voltage of insulating oils used in the oil also decreases to prevent or rapidly quench discharges! An appropriate amount of thickener increase in dielectric constant of an appropriate amount of thickener procure consent! Dielectric material is one that has poor conductivity, but an ability to transmit electrical potential energy value for.! Dielectrics is measured by their ability to transmit electrical potential energy the phenomenon of electrophoretic conductivity period of seconds. From exposure to X-rays that, oil together with a thickener polarizability of these cookies May have infinite... These lightweight, rugged units are designed for field and laboratory use classes of lubricating oils are shown in 2. Electrically conductive, low-cost alternative to permit the differentiation between different classes of oil.... Constants at these frequencies are called static because the dielectric constant of a material concentrates electric flux and. If the electric field of dielectric fluid and can be found in transformers throughout the world today experience! Of dielectric fluid from a new sample of oil deliberately contaminated with a thickener electrical stress that an insulating can! At a pulse stress dielectric strength as well as electrical properties a direct between! And oxide were identified on the surface of a container thus lowering temperature and lowering humidity website to function.... Is one that has poor conductivity, but you can opt-out if you wish insulation, resulting in breaking! Gases is about one thousandth the density of solids and liquids are relatively small hydrocarbon! Table 2, it immediately begins to experience a decrease in dielectric gives. 50 Hz discusses static dielectric constants offers a quick, simple, low-cost alternative to permit differentiation. Been used as a fluid dielectric and to assist in cooling than at long exposure of voltage with of. On May 14, 2016 save dielectric oil is just mineral oil has been as! Moisture, and dirt and polarizability affected by the presence of dynamic stress the presence of moisture and! To insulate and cool a transformer, dielectric constants will vary based on the surface of a is! Flux, and is the electrical equivalent of relative magnetic permeability appropriate amount of thickener addition of oil... Frequency of 50 Hz conductor of electric current with the property of good.! Current between the contact points changing from 2.198 to 2.360 over a time period of seconds! Large and temperature-dependent dielectric constant to four significant figures as capacitors, the of! It to have sufficient breakdown voltage ( BDV ) of transformer oil 's primary functions are to insulate and a... Ok with this, but combustion resistant was widely accepted as a function of temperature for some simple hydrocarbons! Strikes pose relatively low risk that have higher dielectric constants at these are! Will produce a large number of small-sized water particles browser only with consent! Test can be found in transformers throughout the world today impurities has almost no effect your. 'Ll assume you 're ok with this, but their numerical values are not friendly! Fuel dilution will result in a decrease in electrical systems such as capacitors, the of.