The disclosure relates to a gas-insulated load break switch (1) and a gas-insulated switchgear (100) comprising a gas-insulated load break switch (1).
The gas-insulated load-break switch (1) has a housing (2) defining a housing volume for holding an insulation gas at an ambient pressure; a first main contact (80) and a second main contact (90), the first and second main contacts (80, 90) being movable in relation to each other in the axial direction (A) of the load break switch (1); a first arcing contact (10) and a second arcing contact (20), the first and second arcing contacts (10, 20) being movable in relation to each other in an axial direction (A) of the load break switch (1) and defining an arcing region in which an arc is formed during a current breaking operation, wherein the arcing region is located, at least partially, radially inward from the first main contact; a pressurizing system (40) having a pressurizing chamber (42) for pressurizing a quenching gas during the current breaking operation; and a nozzle system (30) arranged and configured to blow the pressurized quenching gas onto the arc formed in the quenching region during the current breaking operation, the nozzle system (30) having a nozzle supply channel for supplying at least one nozzle (33) with the pressurized quenching gas.
The first main contact (80) comprises at least one pressure release opening (85) formed such as to allow a flow of gas substantially in a radial outward direction, wherein the total area of the at least one pressure release opening (85) is configured such that during a supply of the pressurized quenching gas, a reduction of the flow of gas out of the pressure release opening (85) is suppressed.