GN22-12/5000A High-Voltage Disconnector for High-Current Cabinets

The GN22-12 disconnector is a high-voltage switching device with a rated voltage of 12kV, suitable for three-phase AC 50Hz indoor installations. Its main function is to connect, cut off or convert circuits when there is voltage but no load, providing a visible and reliable electrical isolation point for equipment that needs power-off maintenance to ensure maintenance safety.

I. Main Features

This disconnector has a novel structural design, adopts a two-step locking method, with excellent thermal and dynamic stability and small operating force. The conductive part is mainly composed of a knife blade and a static contact. The knife blade is composed of two slotted pieces to increase the heat dissipation area, improve mechanical strength and dynamic stability. The main conductive body adopts T2 copper one-time forming technology, which improves the current carrying capacity. New materials and processes such as epoxy resin insulators and brush plating silver are adopted, with good electrical conductivity, small size and light weight. The outlet terminals are convenient for connecting with vacuum circuit breakers and oil circuit breakers, which can reduce the volume of the switch cabinet and lower the cost.

II. Technical Parameters

The main technical parameters of the GN22-12 series disconnectors are as follows:

Rated voltage: 12 kV

Rated frequency: 50 Hz

Rated current: 1600A, 2000A, 2500A, 3150A, etc.

Rated short-time withstand current (4s): 40 kA (corresponding to 1600A-2000A), 50 kA (corresponding to 2500A-3150A)

Rated peak withstand current: 100 kA (corresponding to 1600A-2000A), 125 kA (corresponding to 2500A-3150A)

Rated insulation level: The power frequency withstand voltage is 42 kV between poles and between poles and ground, and 49 kV at the breaking opening; the lightning impulse withstand voltage is 75 kV between poles and between poles and ground, and 85 kV at the breaking opening.

The rated current range of this series of products covers 2000A to 6300A, and there are multiple derivative models corresponding to different grounding methods (moving contact side grounding, static contact side grounding and double grounding). The product structural forms include flush mounting type, wall penetrating type, flush mounting grounding type, wall penetrating grounding type, etc.

III. Operating Environment and Operation Requirements

The operating environment must meet the following conditions:

Altitude: no more than 1000m (can be extended to 3000m upon special request).

Ambient temperature: -30℃ to +40℃.

Relative humidity: the daily average value is not more than 95%, and the monthly average value is not more than 90% (at +25℃).

Seismic intensity: no more than 8 degrees.

The disconnector does not have arc extinguishing capability, and it is strictly forbidden to operate with load. It must be ensured that the circuit is in a no-load state during operation, and it is usually operated with a CS6-1, CS6-2 manual operating mechanism or a CX-6Ⅱ electric operating mechanism. In the power distribution system, it is often used in conjunction with a circuit breaker to realize circuit switching or change the system operating mode.

IV. Main Applications

The GN22-12 disconnector is mainly used in high-voltage power distribution systems, and its specific applications include:

Power isolation: Form an obvious disconnecting point between high-voltage maintenance equipment and live equipment.

Switching operation: Cooperate with the circuit breaker to change the system operating wiring mode, such as busbar switching in a double-busbar circuit.

Connect or disconnect small current circuits

Its design meets the basic isolation needs of the power system, and has an important impact on the design, establishment and safe operation of substations and power plants.