Product Overview

The LW36-126T (W)/3150-40 Outdoor High Voltage SF₆ Dead Tank Circuit Breaker is a high-performance transmission-class circuit breaker designed for 72.5kV and 126kV, 50Hz three-phase AC power systems. It integrates the circuit breaker and current transformer (CT) into a compact dead tank structure, delivering reliable switching, protection, and control for substations and transmission networks.

The interrupter chamber is horizontally mounted inside a grounded aluminum alloy enclosure and operated by the CT26 spring operating mechanism. Using SF₆ gas as both the insulating and arc-extinguishing medium, the breaker provides outstanding dielectric strength, high interruption capacity, and long electrical service life.

Manufactured with CNC precision machining and equipped with premium bearings from internationally recognized brands such as IKO, INA, and SKF, the LW36-126T offers exceptional mechanical reliability with a mechanical life of up to 10,000 operations.

It is widely used as a line breaker, transformer feeder breaker, bus coupler breaker, and capacitor bank switching breaker in utility substations and high-voltage transmission systems.

Model Designation

LW36-126(W)/T3150-40

Key Features

Integrated Dead Tank Design

The LW36-126T adopts a compact dead tank construction with the interrupter chamber installed inside a grounded aluminum alloy tank. Built-in current transformers eliminate the need for external CTs, reducing installation space, simplifying primary wiring, and lowering project costs.

Benefits include:

• Integrated circuit breaker and CT

• Compact footprint

• Improved operational safety

• Simplified substation layout

• Reduced installation time

Advanced SF₆ Arc-Extinguishing Technology

SF₆ gas serves as both the insulation and arc-quenching medium, providing:

• Excellent dielectric performance

• High short-circuit interruption capability

• No restrike during capacitive current switching

• Long electrical endurance

• Stable operation under severe system faults

The optimized interrupter structure and self-developed arc-extinguishing technology significantly improve switching efficiency while reducing operating energy.

High Mechanical Reliability

All major mechanical components are precision manufactured using CNC machining centers.

Premium imported bearings from IKO, INA, and SKF ensure:

• Smooth mechanical transmission

• Low operating friction

• Stable synchronization

• Long-term reliability

• Mechanical life up to 10,000 operations

Excellent Corrosion Resistance

Designed for long-term outdoor service, the breaker incorporates multiple anti-corrosion measures:

• Stainless steel operating mechanism cabinet

• Hot-dip galvanized structural steel components

• Hot-dip galvanized fasteners

• High-strength support frame

• Excellent resistance to moisture, salt spray, and industrial pollution

The anti-pollution (W) version is particularly suitable for coastal regions and heavily contaminated industrial environments.

Outstanding Current Carrying Capacity

The breaker successfully passes temperature rise tests at 120% of rated current (3,780A), providing excellent thermal margin for continuous operation.

Additional advantages include:

• Low temperature rise

• Stable contact resistance

• Excellent overload capability

• Reliable continuous current carrying performance

Easy Installation and Low Maintenance

The compact structure simplifies transportation, installation, commissioning, and maintenance.

Additional features include:

• Centralized CT26 spring operating mechanism

• Online SF₆ gas density monitoring

• Fast motor charging (≤15 seconds)

• Reduced maintenance workload

• Long inspection intervals

Technical Specifications

Electrical Ratings

Insulation Performance

Altitude correction factor K:

• 2000 m: K = 1.13

• 3000 m: K = 1.28

Mechanical Performance

CT26 Spring Operating Mechanism

SF₆ Gas Characteristics

Dimensions & Installation

Standardized mounting dimensions enable quick installation on conventional concrete substation foundations.

Main Components

Typical Applications

The LW36-126T SF₆ Dead Tank Circuit Breaker is suitable for a wide range of high-voltage transmission and substation applications, including:

• 72.5kV and 126kV transmission substations

• Utility transmission and distribution networks

• Transformer feeder protection

• Bus coupler applications

• Capacitor bank switching

• Industrial power substations

• Renewable energy grid connections

• Heavy industrial facilities

• Coastal and high-pollution environments

Why Choose the LW36-126T?

• Integrated dead tank circuit breaker with built-in current transformers

• Advanced SF₆ gas insulation and arc-extinguishing technology

• Rated voltage up to 126kV

• Rated current 3150A

• 40kA short-circuit breaking capacity

• Premium IKO, INA, and SKF bearings for superior mechanical reliability

• Mechanical life of 10,000 operations

• Stainless steel control cabinet and fully hot-dip galvanized steel structure

• Excellent corrosion resistance for harsh outdoor environments

• Online SF₆ gas density monitoring

• Fast energy storage within 15 seconds

• Easy installation with low maintenance requirements

• Ideal for transmission substations, utility grids, capacitor banks, and transformer switching

Customization Services

Weisho Electric provides comprehensive customization services to meet various utility and EPC project requirements.

Available options include:

• Different rated currents

• Anti-pollution (W) configurations

• Control voltage customization

• Auxiliary contact configurations

• Current transformer ratios and accuracy classes

• OEM and private label manufacturing

• Factory Acceptance Test (FAT)

• Complete technical documentation and engineering support

Our engineering team can tailor the LW36-126T SF₆ Dead Tank Circuit Breaker to comply with IEC, ANSI, or project-specific technical specifications for global power transmission projects.