Three-positions disconnector for medium voltage panels

1. A three-positions disconnector for a three-phase system, characterized in that it comprises, for each phase:

an insulating casing which comprises a first cavity and a second cavity separated by an insulated partition wall, a through hole being present in said partition wall between said first and second cavity;

a first fixed contact suitable for ground connection;

the first cavity housing:

a second fixed contact electrically connected to a corresponding branch conductor of a bus-bar system;

at least a portion of a movable contact pivotally mounted on a support positioned in said first cavity, said support extending through said hole to form a first electrical terminal, said movable contact being electrically connected to a first electrical terminal;

the second cavity housing said first electrical terminal;

the disconnector also comprising an operating mechanism and a kinematical chain linking said movable contact with said operating mechanism, said movable contact being movable between a first position in which it is coupled to said second fixed contact, a second position in which it is isolated from both said second and first fixed contacts, and a third position in which it coupled to said first fixed contact.

2. The three-positions disconnector of claim 1 , characterized in that said insulating casing is a single-block casing made of polymeric material.

3. The three-positions disconnector of claim 1 , characterized in that said movable contact comprises a bar-shaped element having a first end pivotally connected to said support and a second end that is movable along an arc, said first and second fixed contacts being positioned in two points of said arc.

4. The three-positions disconnector according to claim 3 , characterized in that said support of the movable contact is positioned in said first cavity on said partition wall in correspondence of said through hole.

5. The three-positions disconnector according to claim 4 , characterized in that said support of the movable contact and said second contact are positioned in said first cavity at a different level with respect to a lateral view of said insulating casing.

6. The three-positions disconnector according to claim 1 , characterized in that said kinematical chain comprises a rotary shaft operatively connected to said operating mechanism and, for each phase, a first crank rigidly coupled to said shaft and a connecting rod which connects said crank to said movable contact.

7. The three-positions disconnector according to claim 5 , characterized in that said connecting rod is connected to said bar-shaped element at a point between said first and second end thereof.

8. The three-positions disconnector according to claim 1 , characterized in that said operating mechanism comprises a handle bar.

9. A Medium Voltage panel, characterized in that said it comprises a three-positions disconnector according to claim 1 .

10. A three-positions disconnector, characterized in that it comprises, for each phase;

an insulating casing which comprises a first cavity and a second cavity separated by an insulated partition wall, a through hole being present in said partition wall between said first and second cavity;

a first fixed contact suitable for ground connection:

the first cavity housing:

a second fixed contact electrically connected to a corresponding branch conductor of a bus-bar system;

at least a portion of a movable contact pivotally mounted on a support positioned in said first cavity, said movable contact being electrically connected to a first electrical terminal;

the second cavity housing said first electrical terminal;

the disconnector also comprising an operating mechanism and a kinematical chain linking said movable contact with said operating mechanism, said movable contact being movable between a first position in which it is coupled to said second fixed contact, a second position in which it is isolated from both said second and first fixed contacts, and a third position in which it coupled to said first fixed contact;

a first compartment housing a bus-bar system and a second compartment housing a cable system; said three-positions disconnector being positioned at the interface between said first and second compartments, with said first cavity of said insulating casing facing towards said first compartment and said second cavity of said insulating casing facing towards said second compartment; the panel also comprising a circuit breaker unit having, for each phase, a second electrical terminal connected to said first electrical terminal of said three-positions disconnector, and a third electrical terminal connected to a corresponding cable of said cable system.

11. The Medium Voltage panel according to claim 10 , characterized in that said circuit breaker unit is directly connected to said three-positions disconnector.

12. The Medium Voltage panel according to claim 10 , characterized in that it has a fixed circuit breaker configuration.

13. The three-positions disconnector of claim 2 , characterized in that said movable contact comprises a bar-shaped element having a first end pivotally connected to said support and a second end that is movable along an arc, said first and second fixed contacts being positioned in two points of said arc.

14. The three-positions disconnector according to claim 13 , characterized in that said support of the movable contact is positioned in said first cavity on said partition wall in correspondence of said through hole.

15. The three-positions disconnector according to claim 14 , characterized in that said support of the movable contact and said second contact are positioned in said first cavity at a different level with respect to a lateral view of said insulating casing.

16. The three-positions disconnector according to claim 15 , characterized in that said connecting rod is connected to said bar-shaped element at a point between said first and second end thereof.