PROBLEM TO BE SOLVED: To provide a distribution transformer capable of preventing lightning damages such as the breakage of primary bushing and the disconnection of a primary lead wire due to lightning surges even when the lighting surges intrude into the distribution transformer inexpensively, and to provide a small-sized electrode for protection against lightning to be used as the countermeasure means.;SOLUTION: For the distribution transformer, the electrode for protection against lightning is provided in the air part of the primary lead wire whose one end is electrically connected to a high voltage distribution line through the primary bushing fixed to the sidewall of a grounded outer box and other end is electrically connected to a transformation part housed inside the outer box, the electrode for protection against lightning is provided with an electrode part projected to the inner wall surface of the outer box, and the distal end of the electrode part is separated from the inner wall surface for such an interval that discharge can be performed when an excessive voltage exceeding the maximum using voltage is applied between them. It is preferable that a convex curved surface is formed toward the outer box inner wall surface at the distal end of the electrode part.;COPYRIGHT: (C)2009,JPO&INPIT
展开▼
