What is the function of a breather in a transformer ?
The function of a breather in a transformer is to maintain the integrity of the insulating oil inside the transformer by preventing moisture from entering. Transformers contain insulating oil that can degrade if exposed to moisture, which can lead to reduced dielectric strength and accelerated aging of the transformer. The breather consists of a silica gel or similar desiccant material that absorbs moisture from the air entering the transformer during cooling and heating cycles. By keeping the internal environment dry, the breather helps prolong the lifespan and reliability of the transformer insulation.
An air breather in a transformer refers to the device mounted on the conservator tank of the transformer. It contains a desiccant material (such as silica gel) that absorbs moisture from the air passing through it. As the transformer heats and cools, the volume of oil inside the conservator tank changes. The air breather allows for the exchange of air between the conservator tank and the atmosphere while preventing moisture from entering the transformer. This helps maintain the dielectric properties of the insulating oil and ensures the transformer operates efficiently and reliably over its service life.
Maintenance of a transformer breather involves periodic inspection and replacement of the desiccant material to ensure effective moisture absorption. Over time, the desiccant can become saturated with moisture, reducing its effectiveness. Routine maintenance typically includes checking the color or condition of the desiccant (often indicating saturation) and replacing it as necessary to maintain optimal performance of the breather. Proper maintenance helps extend the life of the transformer and ensures reliable operation by preserving the quality of the insulating oil.
Oil is used in breathers primarily to lubricate the moving parts within the breather mechanism and to enhance its operational efficiency. The breather device may contain valves or mechanical components that require smooth operation to regulate the exchange of air and prevent the ingress of contaminants into the transformer. The presence of oil ensures these components function properly over time, minimizing friction and wear that could affect the breather’s performance. Additionally, oil helps maintain a seal against the external environment, preventing moisture and other harmful substances from entering the transformer through the breather.
The vent pipe in a transformer serves as a conduit for releasing gases generated during the normal operation of the transformer. As the transformer heats up during operation, internal components and insulating materials may produce gases due to thermal decomposition or other chemical processes. These gases need to be safely vented to maintain proper pressure levels inside the transformer and prevent internal pressures from exceeding safe limits. The vent pipe directs these gases to a location where they can safely dissipate, such as an outdoor vent or a gas collection system, ensuring the transformer operates safely and efficiently. Proper venting also helps prevent the accumulation of gases that could degrade the insulating oil or cause mechanical stress within the transformer.