摘要 |
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.
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