Design and drive
The Double side break type (EDB) disconnectors chassis are made of steel. Rotating feet on the chassis carries moving insulators, each phase comprise 2 fixed insulator connected to chasis at both side and one rotating
insulator connected to rotating feet in the middle. Rotating insulators carry current arms.
Current arms are manufactured from aluminum alloy profiles for 123 kV disconnectors and over, up to 123 kV from electrolitic copper. Axis deviation on the insulators can be easily adjusted by the bolts on the rotating feet.
If required, disconnector can be equipped with earthing units. The earthing unit has an individual operating mechanism. All parts have been permanently lubricated and designed to have maintenance free operation.
The steel components are hot-dip galvanized to protect from atmospherical effects. The connection terminals are placed on the insulators at both sides.
High mechanical rigidity
Double break type system ensures high mechanical rigidity and safe current transmission in short circuit. It requires less distance between the phases. The disconnector can be delivered as manual or motor controlled.
Three poles of disconnector and earthing unit could be activated by only one operating mechanism (up to 245 kV). Adjustment is possible through the connection levers placed in between the poles. There is a mechanical and electrical interlocking facility between the disconnector and
earthing units thus, earthing contacts can not be closed when the disconnector is in “closed position”.
Disconnector and earthing unit are operated with an individual operation mechanism. The motion transmitted from the operation mechanism trough the rotating insulator is immediately transferred to the other phases by the cross levers and ensures simultaneous drive of all three phases. Each phase is operated by an individual mechanism over 245 kV disconnectors.
Special locking system
Current arms rotate through rotating insulator that is in the middle of each phase. Because of the lengths of motion transmission pipes between the phases are adjustable, to ensure simultaneous motion for each
phase, the positions can be adjusted accurately. Unnecessary motions are restricted by mechanical stoppers.
Mechanism system ensures electromechanical lock in open and closed position. This interlock prevents motions may be caused by external factors such as short circuit forces, winds, and earthquake. Ice-layers that form because of the bad weather conditions can be broken easily by opening and closing forces of current arms thus opening and closing operation are performed.
The main circuit connections are placed on the insulators and both sides. It is suitable for fixing any kind ofconnection means.
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