An electric switchgear comprising: - a casing having at least one compartment provided with a door; and - a plurality of electrical conductors suitable to be connected to a load; - a multi-phase switching device which is mounted on a truck, said truck being movable inside said compartment between a connected position wherein each phase of said switching device is electrically connected to a corresponding electrical conductor and a withdrawn position wherein each phase of said switching device is electrically separated from the corresponding electrical conductor; - a mechanism adapted for stopping said switching device in a position intermediate between said connected position and said withdrawn position; - an interlocking mechanism keeping said door closed when moving said truck between said connected position and said withdrawn position, characterized in that it said truck comprises - a movable draw-shaped body having a pair of truck lateral plates at least one of which is provided with a protuberance; - a cross member which is suitable to be removably connected inside the compartment at the front part thereof, said cross member being coupled with a cylindrical element having a through hole, wherein at least one spring is positioned between and connected to said cross member and said cylindrical element; and - a worm screw which is connected to said draw-shaped body and has one end which passes through said cross member and is inserted into said through hole of the cylindrical element, said draw-shaped body moving relative to said cross member, and wherein said interlocking mechanism comprises: - a first element mounted on the internal side of said door and provided with a through hole suitable to be aligned with said through hole of the cylindrical element so as to allow said worm screw to be operatively connected to a tool for moving said switching device between said connected position and said withdrawn position; - a first protuberance suitable to engage with/disengage from a first recess provided on a rod which is coupled to and moved by a handle for closing/opening said door, and a movable pin adapted for mechanically interacting with said switching device so as to cause said first protuberance to disengage from/engage with said first recess and allow/prevent opening of said door; - a block connected to said cross member, said block being provided with a second recess and a second protrusion suitable to be interposed between said cylindrical element and said cross member, and an L-shaped pivot which is mounted on the internal side of said door and has one end suitable to enter into said second recess and allows moving said second protrusion away from the position interposed between said cylindrical element and said cross member. - a casing having at least one compartment provided with a door; and - a plurality of electrical conductors suitable to be connected to a load; - a multi-phase switching device which is mounted on a truck, said truck being movable inside said compartment between a connected position wherein each phase of said switching device is electrically connected to a corresponding electrical conductor and a withdrawn position wherein each phase of said switching device is electrically separated from the corresponding electrical conductor; - a mechanism adapted for stopping said switching device in a position intermediate between said connected position and said withdrawn position; - an interlocking mechanism keeping said door closed when moving said truck between said connected position and said withdrawn position, - a movable draw-shaped body having a pair of truck lateral plates at least one of which is provided with a protuberance; - a cross member which is suitable to be removably connected inside the compartment at the front part thereof, said cross member being coupled with a cylindrical element having a through hole, wherein at least one spring is positioned between and connected to said cross member and said cylindrical element; and - a worm screw which is connected to said draw-shaped body and has one end which passes through said cross member and is inserted into said through hole of the cylindrical element, said draw-shaped body moving relative to said cross member, - a first element mounted on the internal side of said door and provided with a through hole suitable to be aligned with said through hole of the cylindrical element so as to allow said worm screw to be operatively connected to a tool for moving said switching device between said connected position and said withdrawn position; - a first protuberance suitable to engage with/disengage from a first recess provided on a rod which is coupled to and moved by a handle for closing/opening said door, and a movable pin adapted for mechanically interacting with said switching device so as to cause said first protuberance to disengage from/engage with said first recess and allow/prevent opening of said door; - a block connected to said cross member, said block being provided with a second recess and a second protrusion suitable to be interposed between said cylindrical element and said cross member, and an L-shaped pivot which is mounted on the internal side of said door and has one end suitable to enter into said second recess and allows moving said second protrusion away from the position interposed between said cylindrical element and said cross member.