Disconnector device for surge arrester and a protection assembly comprising a surge arrester connected to such a disconnector device

A disconnector device for a surge arrester, the disconnector device comprising:

• a housing encompassing a cavity;
• a disconnector provided inside the cavity, having a first terminal connectable to the surge arrester, a second terminal connectable to ground potential, and a movable member provided at the second terminal and being fitted to the cross section of the cavity, and a disconnector cartridge;
• wherein the movable member is movably arranged such in the housing that once the disconnector operates, the movable member is propelled inside the cavity towards an end of the cavity by gas from the disconnector cartridge, and wherein the housing has ventilation openings connecting the cavity to an outside of the disconnector device for releasing gases from the operating disconnector cartridge, the ventilation openings being dimensioned such that no particles harmful size that are potentially capable of igniting a fire can pass the ventilation openings;
• wherein the cavity has an elongated shape, and wherein the housing has a retaining section for retaining the movable member at the retaining section once the movable member was propelled towards the end of the cavity;
• and
• wherein the ventilation openings are slits extending along the cavity in a direction of a longitudinal axis defined by the overall shape of the cavity.