What is Silica Gel Breather of Transformer?

What is Silica Gel Breather of Transformer?

Silica Gel Breather Definition

A silica gel breather is a device used to filter moisture from the air entering a transformer, protecting its insulation.

 Air Flow Mechanism

Transformer oil expansion and contraction cause air to move in and out of the conservator tank, necessitating filtration.

Construction of Silica Gel Breather

The silica gel breather for transformers is simple in design. It is a container filled with silica gel that air passes through. Silica gel absorbs moisture very well. Freshly regenerated gel can dry air to a dew point below -40°C, while well-maintained gel usually operates at around -35°C.

Working Principle of Silica Gel Breather

Silica gel crystals absorb moisture very effectively. As air passes through the breather, the crystals absorb its moisture, ensuring dry air reaches the conservator. Dust particles in the air are trapped by the oil in the oil seal cup. The oil acts as a barrier when there is no airflow. Silica gel crystals change color from dark blue to pink as they absorb moisture. When there is a significant pressure difference between the air inside the conservator and outside, the oil levels in the seal adjust. This movement allows air to pass from the high-pressure to the low-pressure compartment, filtering out dust from the outside air.