Monday, 14 May 2018

What is silica gel and its purpose



Function of Silica Gel Breather
Most of the power generation companies use silica gel breathers fitted to the conservator of oil filled transformers. The purpose of these silica gel breathers is to absorb the moisture in the air sucked in by the transformer during the breathing process.
What is Transformer Breathing?
When load on transformer increases or when the transformer under full load, the insulating oil of the transformer gets heated up, expands and gets expel out in to the conservator tank present at the top of the power transformer and subsequently pushes the dry air out of the conservator tank through the silica gel breather. This process is called breathing out of the transformer.
When the oil cools down, air from the atmosphere is drawn in to the transformer. This is called breathing in of the transformer.
Use of Silica gel breather
During the breathing process, the incoming air may consist of moisture and dirt which should be removed in order to prevent any damage. Hence the air is made to pass through the silica gel breather, which will absorb the moisture in the air and ensures that only dry air enters in to the transformer. Silica gel in the breather will be blue when installed and they turn to pink colour when they absorb moisture which indicates the crystals should be replaced. These breathers also have an oil cup fitted with, so that the dust particles get settled in the cup.
Thus Silica gel breathers provide an economic and efficient means of controlling the level of moisture entering the conservator tank during the breathing process.

Power system MCQ

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