Mog in transformer

What is Transformer Oil? 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 oil-filled Transformer oil is also used to preserve the transformer’s core and windings – as these are fully immersed inside the oil. Another important property of the insulating oil is its ability to prevent oxidation of the cellulose-made paper insulation. The transformer oil acts as a barrier between the atmospheric oxygen and the cellulose – avoiding direct contact and hence minimizing oxidation. The level of transformer oil is typically measured using a Transformer Oil Types There are two main types of transformer oil used in • Paraffin based transformer oil • Naphtha based transformer oil Naphtha oil is more easily oxidized than paraffin oil. But the product of oxidation – i.e. sludge – in the naphtha oil is more soluble than the sludge from the p araffin oil. Thus sludge of naphtha-based oil is not precipitated in the bottom of the transformer. Hence it does not obstruct convection circulation of the oil, means it does not disturb the Although Paraffin oil has a lower oxidation rate than Naphtha oil, the oxidation product (sludge) is insoluble and precipitated at the bottom of the tank. This sludge acts as an obstruction to the transformer cooling system. Another problem with paraffin-based oil that the dissolved waxes inside of it can lead to a high pour p...

A Magnetic Oil level Guage (MOG) is a device used to indicate the position of transformer insulating oil level in conservator of a transformer. This is a mechanical device. A mog in a transformer consists of three main parts: • One float • Bevel gear arrangement • An indicating dial Construction of Magnetic Oil Gauge or MOG One ball type or drum type float is attached with a sufficiently long float arm. One unit of bevel gear is fitted on the other side of the float arm. The other unit of the bevel gear is magnetically coupled with pointer and mercury switch arrangement. The bevel gear arrangement is positioned inside the conservator tank of transformer and dial, pointer and mercury switch are positioned outside the conservator tank. Working Principle of Magnetic Oil Gauge or MOG All large electrical power transformers are therefore provided with a magnetic oil level indicator or magnetic oil gauge. In conventional conservator tank, a light weight hollow ball or drum floats on the transformer insulating oil. The float arm is attached with bevel gear as we already explained during the discussion on the construction of magnetic oil gauge. Naturally, the position of the float goes up and down depending upon the oil level in the conservator and consequently the alignment of float arm changes. Consequently, the bevel gear rotates. This movement of bevel gear is transmitted to the pointer outside the conservator, as this pointer is magnetically coupled with the bevel gear. The p...

A Magnetic Oil level Guage (MOG) is a device used to indicate the position of • One float • Bevel gear arrangement • An indicating dial Construction of Magnetic Oil Gauge or MOG Let’s explain the construction of magnetic oil gauge (MOG) from its dial parts. The dial of this device has a scale from empty to full. It has some intermediate divisions such as 1/4, 1/1, 3/4. The prescribed oil level at either 30 oC or 35 oC ambient temperature may also be indicated on the dial. A mercury switch and bevel gear are fixed with the pointer. When the pointer rotates, the alignment of the mercury switch also changes according to the angle of rotation of the pointer. One ball type or drum type float is attached with a sufficiently long float arm. One unit of bevel gear is fitted on the other side of the float arm. The other unit of the bevel gear is magnetically coupled with pointer and mercury switch arrangement. The bevel gear arrangement is positioned inside the conservator tank of transformer and dial, pointer and mercury switch are positioned outside the conservator tank. Working Principle of Magnetic Oil Gauge or MOG All oil-immersed distribution and electrical Again when oil volume is reduced due to fall in oil temperature, the oil level in the conservator goes down. But it is essential to maintain a minimum oil level in the conservator tank of transformer even at lowest possible temperature. All large electrical power transformers are therefore provided with a magnetic oil leve...

Construction of MOG or Magnetic Oil Gauge Construction of MOG is simple, it consists of a float, Bevel gear arrangement, and indication dial. The indication dial has a scale from empty-fill level to Full. Some MOGs indication dial has a scale of 1/4, 1/2, and 3/4 to show the oil level. In some cases prescribed oil levels at either 30°C or 35°C ambient temperature may also be shown on the MOG dial. The Mercury switch and bevel float are attached to the pointer of the magnetic oil gauge. When the pointer deflects due to a change in the oil level inside the tank, the mercury switch attached to it also rotates. And it gives an alarm when the oil level falls to the fill level. MOG is installed on the conservator tank at a 15 or 30-degree angle for the best view of the dial. And sometimes placed at 0 degrees. As shown in the below diagram. Working Principle of MOG The MOG is a vertical dial-shaped device installed on the conservator tank of the transformer. The oil level shown by the MOG is the same as that inside the transformer tank. As the oil level may rise due to increased load or any fault and fall because of a decrease in the surrounding temperature. The rise and fall of transformer oil can be observed from outside with the help of a Magnetic Oil Gauge. As the change in oil level occurs it deflects the pointer on the dial gauge of MOG to indicate an increased or decreased oil level. Importance of Magnetic Oil Gauge: The Magnetic Oil Gauge is a crucial component of an A lo...

Magnetic Oil Gauge Magnetic Oil Gauge (MOG) is fixed to the conservator tank of the Transformer to indicate oil level in the conservator tank. The oil levels are generally indicated on the MOG dial as ‘Empty’, 1/4, 1/2, 3/4 and ‘Full’. But in between these levels usually 30 0C temperature indication is also shown. This is because oil level in the conservator tank changes according to the ambient temperature. The hotter the temperature, the more will be the oil level in the conservator tank due to expansion and vice versa. So, as the oil level depends on the ambient temperature, we must have an indication to what level the oil is to be filled at a certain temperature. This is why the level is indicated in temperature degrees so that the when the ambient temperature is same as the temperature indicated on that MOG dial, the oil level should reach that mark to ensure that the Transformer has sufficient oil level in the conservator. Whenever oil is to be filled in the conservator tank, the level is to be checked properly and to be set according to the ambient temperature prevailing at the time of filling the oil. • Click to share on Skype (Opens in new window) • Click to share on Reddit (Opens in new window) • Click to share on Tumblr (Opens in new window) • Click to share on Telegram (Opens in new window) • Click to share on Pocket (Opens in new window) • Click to email a link to a friend (Opens in new window) • Click to share on Pinterest (Opens in new window) • Click to pri...

Who We Are Viat is part of a family of companies manufacturing instruments and accessories for power and distribution transformers in India for the last 50 years. We have manufacturing facilities in two cities and dozens of global distributors and warehouses with whom we can ship to any country in the world. Viat supplies to over 500 transformer OEMs in 70 countries and is widely approved by utilities and OEMs globally. Viat America Inc stocksgoods and provides support in North America: What We Do Viat manufactures instruments, components and accessories for power and distribution transformers. Primary focus areas include those relating to pressure, temperature, level, flow and electrical switching. We provide a one stop shop for OEM needs, and specialise in custom requirements

Construction and Working of MOG: This Magnetic Oil Gauge or MOG is composed of a disc indicator (or a red pointer) behind a dial frame and a float linked to said indicator by means of a magnetic field of force. The dial of this device has scale from empty to full. It has some intermediate divisions such as 1/4, 1/1, 3/4. The prescribed oil level at either 30°C or 35°C ambient temperature may also be indicated on the dial depending upon the design of MOG. In some design of MOG, the indicator disc is for one half enamelled white and, for the other half, red. Alternatively the colour proportion visible through the dial glass indicates the respective level position, while the dial face is marked at minimum and maximum oil level and at level corresponding to 20°C and 85°C. The float of Magnetic Oil Gauge, changes its position as the level of oil in