A cylindrical component named as conservator is installed inside the transformer. When you take the transformer to the service center offering transformers repairing services, you will find that the conservator is located at the top of your transformer.
Manufacturers intend this part of the transformer to act as a reservoir for insulating oil. The level of the transformer oil can rise or fall because of the temperature. The temperature can be raised by increase in ambient temperature or due to increased load on the transformer.
A rise in temperature results in oil expansion in the transformer. And the conservator offers space for such oil expansion. The oil level indicator present in the conservator required to be checked and monitored to ensure that the oil level doesn’t get reduced below the alarm limit.
When the oil level rises or falls within the conservator, air makes entry and exits from the chamber. The passing air may contain moisture that can cause the deterioration to the oil. Breathers filled with silica gels are used to expel moisture from the aspirated air.
The silica gels used in the breathers are blue in color when they are dry. The blue turns to pink when it is saturated with moisture and you have to replace it.
Several power generation companies are using silica gel canister breathers installed to the conservator within the oil transformer. However, there is a better solution. As silica gel is a rigid type desiccant, it can only absorb moisture.
Transformer manufacturing companies have started using super-polymer based technology that can absorb 400% of its weight in atmospheric moisture. These new technology-based breathers can be used freely or in tandem with pre-installed silica gel breather. This offers huge benefits to maintenance and equipment costs because it is a big job to change the silica gel.
Every conservator needs a breather, which has a sole purpose of keeping out the moisture. Without a breather, water will enter inside the conservator and over time it will decay and break the bladder. When this happens, water will get entered to the oil. At the end, you have to replace your transformer oil or if the situation is worse, it can result in transformer failure.
And you know if transformer breaks down, your transformer repairing vendor won’t be able to fix the problem and you have to get a new transformer for your place.