Over-voltage protection device

Over-voltage protection device comprising a plurality of stacks (1, 2) of series-connected, identical surge arrester sections (3), mutually electrically connected at their upper and lower ends, in which each arrester section (3) comprises an insulating casing containing a voltage-dependent resistor (4) series-connected with a spark gap assembly (5), and a triggering circuit (7, 8, 16) in parallel with the arrester stacks (1, 2), said triggering circuit comprising a plurality of series-connected control spark gaps (7), corresponding to the number of arrester sections (3) in each arrester stack (1, 2), and a triggering resistor (8) connected in series with the control sparks gaps, and cross-sections containing triggering impedances (16) from a connection point (10, 11) between two control spark gaps (7) only to a corresponding connection point (12, 13 and 14, 15, respectively) between two arrester sections (3) of each of the parallel arrester stacks (1, 2), said triggering circuit having a higher resistance and a lower ignition voltage than said arrester stacks.