Control transformers have aluminium or copper coils and windings for generating electric voltage, which is then transmitted to other equipment using cables. In liquid type transformers, the windings are immersed in a liquid held in a liquid-tight tank. The liquid acts as insulation for the windings. In the process of generating electric current, the windings produce lots of heat that interferes with the productivity of the transformer. The liquid absorbs the heat from the windings and transmits it to the outside of the liquid tank, keeping the windings cool. If you want to buy a liquid type transformer for your business, here are some of the important things that you need to know:
The Type Oil It Has
The transformer oil is the primary insulating and cooling agent in liquid type transformers. This oil can either be naphtha or paraffin based. Due to heat, oxidation occurs in the transformer oil. The process results in the formation of solid sludge, an unwanted precipitate. Naphtha-based transformer oil undergoes oxidation more easily than paraffin based transformer oil. This means that the sludge produced by the naphtha-based oil isn't deposited at the base of the transformer. Therefore, the sludge does not interfere with the circulation of the oil within the storage tank, maintaining the efficiency of the cooling system.
On the other hand, paraffin based oil oxidises at a slower rate than naphtha-based oil. Its sludge is insoluble and hence it is deposited at the bottom of the transformer. This necessitates regular cleaning to main the circulation of the oil. However, paraffin based oil is still useful in most cases because of its availability.
Indoor Versus Outdoor Applications
Are you going to install the liquid type transformer indoors or outdoors? Liquid type transformers are not suitable for indoor applications because of the elevated risk of a fire breakout. Transformer oil is highly flammable and poses a threat to the safety of the occupants of the building. The heat generated by the coils and winding, coupled with the danger of electrical short circuits and sparks increase the chances of a fire. These risks do not exist with dry type transformers (cooled by air or gas), which are better suited for indoor applications.
Improper cooling damages the coils and windings in the transformer. This is why you should keep an eye on the transformer oil levels and operating temperatures. Make sure that your liquid type transformer has a trip and alarm function that will terminate voltage generation or issue audio-visual signal on the pressure and temperature levels of the transformer oil.