Manual for 1HDB 050016-YN-A

2.1 Disconnector: High-voltage disconnectors provide electrical isolation in high-voltage networks by creating a visible isolation distance when switched off. They are operated under no-load conditions and can control small capacitive or inductive currents. The SGF two-column rotary disconnector is a single-pole unit for outdoor installation, which can be coupled to form a 2- or 3-pole group.

2.2 Earthing Switch: One or two earthing switches can be mounted per pole to earth and short-circuit switched-off plant sections.

5.1 General: The disconnector and earthing switch have separate operating mechanisms. A dead-center position is reached before end positions to prevent automatic operation due to short-circuits or external influences like storms or earthquakes.

5.2 Disconnector: The operating mechanism moves the disconnector via a rotary pedestal and diagonal rod. The current paths rotate 90°, establishing connection between contacts during switching-on. Current is transferred via tulip-type contacts to high-voltage terminals. Coupling rods ensure simultaneous movement of poles in a group.

5.3 Earthing Switch: The operating mechanism moves an earthing-switch shaft, which swivels a tubular contact arm to connect with the earthing contact. Earthing connections link the contact arm to the base frame.

5.4 Interlocking: Mechanical and/or electrical interlocking prevents the disconnector from being ON when the earthing switch is ON, and vice versa. Mechanical interlocks are factory-fitted and cannot be retrofitted.