Design and drive
Strong and functional structure
The center-break type disconnector (EDC)’s chassis are made of steel. Support insulators are on top of rotating feet on the chassis. The support insulators carry aluminum current arms. Axis deviations can be easily corrected by adjusting bolts on the rotating feet. If required, disconnector can be equipped with an earthing unit. The earthing unit has an indivual operating mechanism. All parts are designed to have maintenance free disconnectors. The steel components are hot-dip galvanized to protect disconnectors from atmospherical effects.
Separate control systems
The disconnector and earthing units are operated with separate control systems. The motion transmitted to the rotating feet from the operating mechanism, is immediately transferred to the other phases by the cross levers and ensures simultaneous drive of all three phases. Current arms are rotated 90 degree and become parallel each others when EDC is open. Depends on the requirements, disconnectors can be delivered manual or motor controlled. All of three disconnectors’ phases are activated by only one operating mechanism (up to 245 kV) and earthing unit is activated by another separated operating mechanism. Adjustment is possible with the motion pipes placed between the phases. There is a mechanical and electrical interlocking facility between disconnector and earthing units. Thus the earthing blade cannot be closed when the disconnector is in “closed” position.
Ice-layers formed 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
Disconnectors are connected to the system through the terminals. These terminals’ are cylindrical, and they are made of electrolytic copper with silver coating these terminals rotate also on their axis. These terminals’ diameters and lengths are variable depends on the disconnectors’ voltage and current ratings. There is one / two earthing bolt on the chassis for earthing connections.
Parallel installation/Serial installation
|See also :|| |