| 摘要 |
FIELD: electricity.SUBSTANCE: overvoltage protection element contains body (2), at least one overvoltage-limiting component (3) placed in body (2), for example varistor or overvoltage protection gas-filled discharger, and two contact elements (4, 5) for electric connection of overvoltage protection element (1) to protected current or signal path. In normal condition of the protection element (1) contact elements (4, 5) are in electrically conductive contact with one pole of voltage-limiting component (3) respectively. Inside the body thermal expansion material (6) is placed so that at thermal overload of the overvoltage-limiting component (3, 3') position of this overvoltage-limiting component (3, 3') in result of expansion of thermal expansion material (6) is variable in regard to position of contact of contact elements (4, 5) so that at least one pole of the overvoltage-limiting component (3, 3') is not in electrically conductive contact with the respective contact element (4, 5).EFFECT: providing reliable electrical connection in normal condition and reliable disconnection of the defective overvoltage-limiting component (2).24 cl, 12 dwg |
