Gw4 Disconnect Switch

Zhejiang Usune Electric Co., Ltd. is a professional factory integrating R&D, design, production, and sales. Its main products include 12kV～245kV indoor and outdoor high-voltage vacuum circuit breakers, SF6 circuit breakers, load switches, and various disconnecting switches. It is a trusted professional supplier for power engineering projects both domestically and internationally.

The Usune Gw4 Disconnect Switch is specifically designed for three-phase AC 50Hz/60Hz power systems. Its primary function is to connect or disconnect high-voltage circuits under energized, no-load conditions and to provide visible electrical isolation clearance for the maintenance of busbars, circuit breakers, transformers, and other high-voltage equipment.

1. Standards Implemented

-GB 1985-2004: AC High Voltage Disconnect Switches and Grounding Switches
-IEC 62271-102: High Voltage Switchgear and Controlgear
-GB/T 11022: General Specifications for High Voltage Switchgear and Controlgear

2. Design Types

GW4 Series: Double-post insulator, horizontal rotating, interrupted type

Structural Features

1. Double-post insulator structure, two post insulators per phase rotate horizontally 90° synchronously.
2. Main contacts are center-broken, silver-plated copper contacts, low contact resistance, and good conductivity.
3. Base is made of hot-dip galvanized steel, with sealed bearings, corrosion-resistant and durable.
4. GW4 Disconnect Switch can be equipped with single-sided or double-sided grounding switches, with mechanical interlocking to ensure operational safety.
5. Operating mechanism can be manual (CS14G, CS17G) or electric (CJ6B, CJ11, XCJ-I).

Main Technical Parameters

Practical Application Case

A 110kV... Wind Power Substation Project

This project is located in a northern region with significant temperature differences, requiring high equipment reliability and cold resistance. The project selected multiple Usune GW4 Disconnect Switches, equipped with electric mechanisms and double-sided grounding switches. For many years since commissioning, the equipment has operated stably, with reliable mechanical actions and excellent corrosion resistance, effectively ensuring substation maintenance safety and daily operation efficiency, earning high praise from the user.

Main Technical Parameters

Outer Dimensions

INSTALLATION & COMMISSIONING

1. Inspection Before Installation

• Insulators: No cracks, damage, or dirt.
• Contacts: Clean, silver-plated surface intact.
• Fasteners: All bolts tightened.
• Mechanism: Smooth rotation; lubricate moving parts.

2. Adjustment

• Insulator verticality: Adjust with shims (max 3mm per location).
• Three-phase synchronization: Adjust crank-arm and linkage rods.
• Contact pressure: Ensure proper insertion and pressure.

OPERATION

• Only operate under NO LOAD; confirm circuit breaker is open.
• Manual operation: Use operating handle; avoid excessive force.
• Motorized operation: Use local/remote control; monitor position.
• Interlock: Do not force operation if interlocked.

MAINTENANCE

• Periodic overhaul: Every 1–2 years.
• Clean insulators and contacts; apply industrial vaseline.
• Lubricate bearings and transmission parts.
• Check for loose bolts, worn contacts, and insulator damage.
• After short-circuit: Inspect immediately.

TROUBLESHOOTING

• Cannot operate: Check interlock, jammed linkage, or motor fault.
• Asynchronous phases: Adjust cross-linkage rods.
• Contact overheating: Clean and retighten; check silver plating.

Project Reference

Cas-space Rocket Launch Project

Test Report

FAQ

Q1: Can the GW4 Disconnect Switch be opened or closed under load?

A: No. The GW4 Disconnect Switch is only suitable for isolation and switching under voltage-only, no-load conditions. It does not have arc-extinguishing capabilities and is strictly prohibited from operation under load. It must be used in conjunction with a circuit breaker.

Q2: What is the function of the mechanical interlock of the grounding switch?

A: The mechanical interlock enforces a safe operating sequence: main switch open → grounding switch closed; grounding switch open → main switch closed, preventing misoperation and ensuring the safety of maintenance personnel.

Q3: Can this product be used in high-altitude or extremely cold regions?

A: The standard type is suitable for environments with an altitude of ≤2000m and a temperature of -40℃ to +40℃, which can meet the needs of most outdoor substations; for special high-altitude or heavily polluted areas, reinforced insulation and anti-corrosion solutions can be customized.