Switch-fuse module

A ring main unit comprising a switch fuse module including:

• at least one fuse;
• and
• at least one fuse canister having the at least one fuse inside;
• the security device including:
• at least one slider configured to linearly move between an open slider position and a closed slider position;
• at least one earthing switch that i) is galvanically connected to an end of the at least one fuse, ii) is operable between an open and a closed state, iii) is designed to earth the end of the at least one fuse in the closed state, and iv) is coupled to the at least one slider in such a manner that the open slider position effects the open state of the at least one earthing switch and the closed slider position effects the closed state of the at least one earthing switch;
• an energy-storing propulsion element configured to move the at least one earthing switch from the open to the closed state when discharging;
• and
• a locking mechanism adapted for blocking access to the at least one fuse in a locked state and for releasing access to the at least one fuse in an unlocked state,
• wherein the at least one slider is coupled to the locking mechanism in such a manner that the at least one slider is in the closed slider position while the locking mechanism is in the unlocked state,
• so that the at least one fuse may only be accessed if it is ensured that the at least one fuse is earthed,
• wherein the energy-storing propulsion element is arranged at a back panel of the at least one slider located longitudinally opposed to a front edge of the at least one slider.

A method of operating a switch-fuse module having a security device, the switch-fuse module comprising:

• at least one fuse;
• and
• at least one fuse canister having the at least one fuse inside;
• the security device including:
• at least one slider configured to linearly move between an open slider position and a closed slider position;
• at least one earthing switch that i) is galvanically connected to an end of the at least one fuse, ii) is operable between an open and a closed state, iii) is designed to earth the end of the at least one fuse in the closed state, and iv) is coupled to the at least one slider in such a manner that the open slider position effects the open state of the at least one earthing switch and the closed slider position effects the closed state of the at least one earthing switch;
• an energy-storing propulsion element configured to move the at least one earthing switch from the open to the closed state when discharging;
• and
• a locking mechanism adapted for blocking access to the at least one fuse in a locked state and for releasing access to the at least one fuse in an unlocked state,
• wherein the at least one slider is coupled to the locking mechanism in such a manner that the at least one slider is in the closed slider position while the locking mechanism is in the unlocked state,
• so that the at least one fuse may only be accessed if it is ensured that the at least one fuse is earthed,
• wherein the energy-storing propulsion element is arranged at a back panel of the at least one slider located longitudinally opposed to a front edge of the at least one slider;
• and
• wherein the method includes the steps of:
• a) moving the at least one slider from the closed slider position to the open slider position i) to bias or charge the energy-storing propulsion element, ii) to turn the at least one earthing switch to the open state, and iii) to lock the locking mechanism for blocking access to the at least one fuse;
• and
• b) moving the at least one slider from the open slider position to the closed slider position i) to move the at least one earthing switch from the open to the closed state while the energy-storing propulsion element discharges, for earthing the end of the at least one fuse, and ii) to unlock the locking mechanism for releasing access to the at least one fuse.