SURGE PROTECTION DEVICE, COMPRISING AT LEAST ONE SURGE ARRESTER AND ONE SHORT-CIRCUIT SWITCHING DEVICE WHICH IS CONNECTED IN PARALLEL WITH THE SURGE ARRESTER, CAN BE THERMALLY TRIPPED AND IS SPRING-PRETENSIONED

摘要

The invention relates to a surge protection device, comprising at least one surge arrester and one short-circuit switching device which is connected in parallel with the surge arrester, can be thermally tripped and is spring-pretensioned, wherein the abovementioned means form one physical unit. The thermal tripping means is arranged in the region where heating of the surge arrester is expected when it is overloaded, and operating or surge current does not flow through said thermal tripping means. The thermal tripping means is in the form of a stop part which releases an unlocking slide of the switching device in the event of thermal overload. The switching device has two opposite contact pieces, wherein at least one of the contacts is of moveable design and is under spring pretension in the closing direction of the switching device. The opening state of the switching device is ensured by the unlocking slide and is released by the thermal tripping means for closing the switching device.