GN30-12 Rotary Disconnector (Indoor)

The GN30-12 indoor AC disconnector (isolator) is intended for making and breaking, without load, sections of medium-voltage networks up to 12 kV (50/60 Hz) and for safe earthing/grounding of de-energized circuits. The GN30-12 series is a three-pole, rotary double-break design with a very compact two-plane layout, optimized for installation in metal-clad/metal-enclosed switchgear, XGN/HXGN panels and RMU cabinets where footprint, reliability and service access are critical.

Application and scope

The GN30-12 provides a visible isolation gap for operational switching, maintenance and repair in 6–12 kV distribution systems - in metal-clad/metal-enclosed switchgear lineups, busbar compartments, cable/feeder/transformer bays, unit substations and MV switchrooms of primary/secondary substations and modular switchgear. It addresses typical project queries like “12 kV disconnector buy/price/spec” and engineering needs:

operational isolation (a clear, visible break) with enhanced dielectric margins thanks to the double-break path and optimized creepage distances;
work-zone safety via a built-in earthing switch in GN30-12D executions; supports portable grounds where required;
sectionalizing, maintenance, bus-tie and busbar transfer switching without load; integration in XGN15/HXGN panels, RMU and compact unit substations;
interfaces cleanly with vacuum circuit breakers, instrument transformers and protection & control systems, incl. renewable generation, mining, oil & gas, cement, metals and data-center infrastructure;
status indication and remote control readiness (limit switches for dry-contact telemetry and optional motor operator); key/method-based interlocks supported;
global market adaptability (Europe, USA, Asia, Africa): 50/60 Hz marking, IEC-aligned ratings; ANSI/IEEE references for metal-clad assemblies as applicable by project;
cabinet footprint optimization through rotary kinematics and multiple terminal orientations (parallel/vertical), ideal for metal-clad and compact switchgear with limited depth.

A compact build and three-position logic (CLOSED - OPEN - EARTHED) simplify standardization across substation projects. Available drives include manual CS6-1 and motorized options, with left/right shafting and multiple phase center distances to match panel architecture.

Technical data (12 kV, rotary, double-break)

Rated voltage, kV	10
Maximum system voltage, kV	12
System frequency, Hz	50/60
Rated continuous current, A	400; 630; 1000; 1250; 1600–3150
Short-time withstand current (4 s), kA	12.5; 20; 31.5; 40
Peak withstand (dynamic), kA	31.5; 50; 80; 100
Phase center distance P, mm	210; 230; 250; 275 (by project)
Mechanical endurance (main path), ops	≥ 2000
Installation category	Indoor service (per IEC 62271-1 service conditions)

Service conditions (IEC/IEEE)

Location: indoor switchgear rooms, unit substations and cabinets;
Ambient temperature: -25 °C to +40 °C; Relative humidity: up to 95% daily / 90% monthly (no condensation);
Altitude: up to 1000 m (higher altitudes by insulation derating/project rules);
Seismic capability: up to Zone 8 (by project); Pollution degree: II; atmosphere free of corrosive gases/aerosols and excessive vibration per MV switchgear norms.

Layout and construction of GN30-12

Rotary double-break knife - contacts arranged on two planes of a common frame; rotary motion reduces operating force and depth;
Post insulators (porcelain/epoxy) with increased creepage; welded base frame with adjustment slots;
Earthing switch (GN30-12D) with mechanical interlock to the main knife;
Operating mechanisms: manual CS6-1 (standard) or motor operator (on request); limit switches for CLOSED/OPEN/EARTHED telemetry;
Terminal options: parallel/vertical pads on one or both sides; left/right operating shaft; mounting above/below the breaker compartment.

Assembly	Function	Features
Base frame	Mounting of three poles & drive	Welded; high rigidity; precise adjustment
Rotary knife (double-break)	Visible isolation / earthing	Low operating force; stable contact pressure
Post insulators	Dielectric support	Porcelain/epoxy; extended creepage
Earthing switch	Operator grounding	Hard interlocks with main knife
Drive / IO	CLOSED-OPEN-EARTHED	CS6-1 or motor; dry-contact limit switches

Safety and interlocks

Three fixed positions prevent any simultaneous main-path closure with the earthing switch;
Mechanical/key interlocks with doors and the associated circuit breaker;
Visible break confirms the de-energized state prior to work;
Provision for sealing the operating handle and mounting of position micro-switches;
Dedicated earthing points for portable grounds during planned work.

Versions and options

GN30-12 (without earthing) and GN30-12D (with integrated earthing switch);
left/right drive; terminal orientation: parallel/vertical (one/both sides);
connection types for bus packages, cable lugs and flexible bars;
porcelain/epoxy insulators; phase centers 210/230/250/275 mm;
limit switches for status indication; motor operator for remote control/SCADA.

Option	Description	Purpose / note
GN30-12D (earthing)	Earthing knife interlocked with main path	Operator grounding of isolated section
Limit switches	Dry contacts for CLOSED/OPEN/EARTHED	Status/remote indication & interlocking
Motor operator	Three-position electric drive	Remote control/automation
Interlock kit	Mechanical/key interlocks	Prevents incorrect operation

Standards and compliance

IEC 62271-102 / EN IEC 62271-102 - High-voltage switchgear and controlgear - AC disconnectors and earthing switches;
IEC 62271-1 / EN 62271-1 - High-voltage switchgear and controlgear - Common specifications;
IEEE/ANSI references for North America: IEEE C37.20.2 (metal-clad switchgear assemblies), IEEE C37.100.1 (common requirements). Project-specific application per switchgear type and local code.

Partnering and integration

We supply drawings/specs from pre-bid packages to full manufacturing documentation;
Design adaptation to your facilities (tooling, machining, finishing, assembly);
Support for type/routine testing, FAT/SAT, operator training and first-series builds.

Documentation offered

Part and assembly drawings (DWG/DXF, specs, BOM), 3D models (STEP/IGES/Parasolid);
Wiring diagrams and assembly/adjustment instructions;
Test programs & protocols, product datasheet and user manual.

Why work with us

- Ready-to-manufacture documentation without building a large in-house engineering team.
- Rapid move to serial production with minimal rework.
- Expert guidance on manufacturing and testing of GN30-12, including fixtures and quality-control plans.