Abstract: The device comprises a three-pole lightning arrester, switch means having conductive blades, trigger means having a trigger fuse piece which is thermally connected to the lightning arrester, and conductor means which define input and output line terminals and a ground terminal. The conductor means provide links between the input terminals and the output terminals, between the line electrodes of the lightning arrester and the input terminals, and between a ground electrode of the lightning arrester and the ground terminal. The trigger piece maintains the blades in their first position until a heating limit temperature above which the piece melts and enables the blades to be resiliently returned to their second position. The trigger piece is made up of a recessed central body bearing against the lightning arrester, and of blade-retaining members positioned on either side of the central body so as to secure the blades to the trigger piece.

Abstract: The invention relates to a connection strip for transmission lines, having two rows of tags on a tag block for the pairs of conductors that define the lines, and having lightning arresters connected in parallel with the lines. The tag block has three rows of chimneys on its front face for the two rows of tags for the conductors, and a third row of tags for the lightning arresters, with the lightning arresters being mounted in a protection strip which is itself removably mounted on the third row of chimneys. The invention is applicable to telecommunications.