126KV Outdoor SF6 Circuit Breaker

The 126KV Outdoor SF6 Circuit Breaker (model LW36-126) is a high-voltage transmission-class switching device designed for power grid substations, utility transmission systems, and large-scale industrial electrical networks. It is widely used for control, protection, and switching of load current, overload current, and short-circuit fault current, and can also function as a tie circuit breaker in interconnected power systems.

This 126KV Outdoor SF6 Circuit Breaker adopts sulfur hexafluoride (SF6) gas as the arc-quenching and insulation medium, combined with a single-column, single-break per pole structure. During interruption, the self-energy arc extinguishing principle generates high-speed gas flow inside the arc chamber to efficiently cool and extinguish the arc, ensuring stable breaking performance under high fault conditions.

Equipped with a CT-driven motor spring operating mechanism and a three-stage mechanical linkage system, the LW36-126 offers precise switching performance, high mechanical reliability, and excellent long-term operational stability in demanding outdoor environments.

Product Appearance

Product Dimensions Diagram

Operating Environment

• Installation altitude: ≤ 3000 meters above sea level
• Ambient temperature: -30°C to +40°C
• Maximum wind speed: ≤ 34 m/s
• Pollution level: Class III (25 mm/kV)

Technical Parameters

Product Features

• Advanced SF6 gas insulation ensures excellent arc extinction and dielectric performance.
• Single-column, single-break pole design reduces mechanical complexity and improves reliability.
• High breaking capacity up to 40kA for transmission-level fault interruption.
• CT-driven spring operating mechanism ensures stable and precise switching operation.
• Suitable for harsh outdoor environments with strong resistance to pollution, wind, and temperature variations.
• Long mechanical life with low maintenance requirements for grid operators.
• Compatible with modern substation automation and remote control systems.

Product Structure & Working Principle

The 126KV Outdoor SF6 Circuit Breaker consists of an SF6 gas-filled arc extinguishing chamber, current transformer integration, operating mechanism, insulating support structure, and steel enclosure system. The SF6 gas acts as both insulation and arc-quenching medium, providing high dielectric strength and rapid recovery after interruption.

During fault conditions, the operating mechanism drives the moving contact to separate, generating a high-speed SF6 gas flow inside the arc chamber. This airflow rapidly cools and deionizes the arc, ensuring safe interruption of high-voltage fault currents. The three-stage mechanical linkage system ensures synchronized pole operation and high breaking consistency.

Applications

• High-voltage transmission substations
• Power grid interconnection systems
• Utility transmission and distribution networks
• Hydropower and thermal power stations
• Industrial high-voltage power systems
• Large-scale infrastructure and energy projects
• Railway and transportation power systems

Frequently Asked Questions

What is a 126KV Outdoor SF6 Circuit Breaker used for?

It is used to interrupt and control high-voltage electrical currents in transmission networks, ensuring safe operation of substations and power systems during faults or switching operations.

Why is SF6 gas used in circuit breakers?

SF6 gas has excellent insulation and arc-quenching properties, allowing efficient interruption of high-voltage fault currents while maintaining compact equipment size.

Is the LW36-126 suitable for outdoor installation?

Yes. The 126KV Outdoor SF6 Circuit Breaker is specifically designed for outdoor substations and can operate reliably under harsh environmental conditions.

What are the advantages over traditional circuit breakers?

Compared with oil-based breakers, SF6 circuit breakers offer higher reliability, lower maintenance, faster arc extinction, and better performance under high-voltage conditions.