Natural and forced cooling
Providing the correct natural ventilation of the transformer room is a crucial perequisite of the transformer performance. The working conditions depend on the insulating material used and defined by the Standards in force IEC 60076. EBG suggests making windows on the walls of the room. The cast resin transformer has a considerable thermal inertia and is able to withstand overloaded situations of a short duration (IEC 60076-12). The overload capacity depends on the continuous load, which is present, and on the external temperature.
For special applications in which temporary power increases above the nominal values are necessary, it is suggested the use of forced ventilation. The ventilation kit is provided with a centralization box to control the fans by the dedicated relay. Transformers fitted with ventilation kit, the power may be increased up to 40%. This is applicable to power transformers up to 10 MVA.