Abstract: A vacuum circuit breaker 10 comprising a vacuum interrupter 12 coupled between upper 18 and lower 20 terminals and being operable to make or break an electrical connection between the upper and lower terminals. The circuit breaker has a body 22 formed from electrically insulating material, the vacuum interrupter being located in an internal chamber of the body. The lower terminal 20 comprises a hollow body 26 that forms part of the internal chamber and which is shaped and dimensioned to allow the vacuum interrupter 12 to pass through it. An electrical connector device 50 has a movable part 52 that is connected to the movable contact and an annular fixed part 54 that is connected to the lower terminal 20. The movable part 52 is connected to the first part 54 by flexible connectors 56, and has a socket (58) for engaging an electrical connector 60 of the vacuum interrupter 12. A pulling rod 16 is coupled to the movable contact via the electrical connector 60.

Abstract: A vacuum circuit breaker comprising a vacuum interrupter (12) coupled between upper (18) and lower (20) terminals and being operable to make or break an electrical connection between the upper and lower terminals. The circuit breaker has a body 22 formed from electrically insulating material, the vacuum interrupter being located in an internal chamber of the body. The circuit breaker body is arranged to provide an isosceles triangle between the upper (C) and lower (A) terminal connection interfaces. This allows the same design of both upper and lower external connectors 80, 82. A pulling rod (16) coupled to the vacuum interrupter comprises a core (70) of heat-resistant plastic co-moulded with a shell (72) formed from impact resistant plastic.

Abstract: A vacuum circuit breaker comprising a vacuum interrupter (12) coupled between upper (18) and lower (20) terminals and being operable to make or break an electrical connection between the upper and lower terminals. The circuit breaker has a body 22 formed from electrically insulating material, the vacuum interrupter being located in an internal chamber of the body. The circuit breaker body is arranged to provide an isosceles triangle between the upper (C) and lower (A) terminal connection interfaces. This allows the same design of both upper and lower external connectors 80, 82. A pulling rod (16) coupled to the vacuum interrupter comprises a core (70) of heat-resistant plastic co-moulded with a shell (72) formed from impact resistant plastic.

Abstract: A vacuum circuit breaker 10 comprising a vacuum interrupter 12 coupled between upper 18 and lower 20 terminals and being operable to make or break an electrical connection between the upper and lower terminals. The circuit breaker has a body 22 formed from electrically insulating material, the vacuum interrupter being located in an internal chamber of the body. The lower terminal 20 comprises a hollow body 26 that forms part of the internal chamber and which is shaped and dimensioned to allow the vacuum interrupter 12 to pass through it. An electrical connector device 50 has a movable part 52 that is connected to the movable contact and an annular fixed part 54 that is connected to the lower terminal 20. The movable part 52 is connected to the first part 54 by flexible connectors 56, and has a socket (58) for engaging an electrical connector 60 of the vacuum interrupter 12. A pulling rod 16 is coupled to the movable contact via the electrical connector 60.

Abstract: A method of controlling a circuit breaker that has a movable contact and an actuator for moving the movable contact between an open position and a closed position. With the movable contact in the open position, a voltage is applied to the actuator to cause the movable contact to move towards the closed position. The voltage is applied for a limited time period ending before the movable contact reaches the closed position. At the end of the limited time period, the voltage is adjusted to reduce the acceleration exerted on the contact. The voltage is subsequently increased just before, after, or substantially at the same time as the contact reaches its closed position.