Safety device for a power transformer, and related power transformer using such a safety device

摘要

Safety device for a power transformer containing a cooling liquid, comprising: - a shaped body having an inner chamber which is suitable to be at least partially immersed in the cooling liquid and inside which gas can accumulate; - a first floating element and a second floating element suitable to be at least partially immersed in and moved by the cooling liquid; - switching means suitable to be actuated by the first floating element when the gas accumulated is such that the level of the cooling liquid in the inner chamber reaches a predetermined first threshold level and by the second floating element when the gas accumulated is such that the level of said cooling liquid in the inner chamber reaches a lower predetermined second threshold level, respectively. The first and second floating elements are mounted on and move linearly relative to one or more corresponding guiding supports.