Current Transformer Circuit Breaker

A Current Transformer Circuit Breaker is an integrated medium-voltage switching device that combines vacuum arc interruption technology with built-in current transformer measurement functions. Designed for power distribution networks, substations, industrial facilities, and renewable energy systems, it provides accurate current sensing, reliable fault protection, and simplified switchgear installation in one compact solution.

Unlike conventional configurations that require separate current transformers installed outside the circuit breaker, this integrated design places precision CT components directly within the breaker structure. The result is reduced secondary wiring complexity, improved measurement accuracy, shorter installation time, and enhanced reliability for modern medium-voltage power systems.

Our vacuum circuit breaker solutions cover a wide range of applications, including the 40.5KV Vacuum Circuit Breaker for high-capacity distribution networks, the Outdoor Vacuum Circuit Breaker for exposed environments, and the 35KV Substation Circuit Breaker for utility and industrial substations. For higher voltage requirements, our High Voltage Vacuum Circuit Breaker platform provides extended insulation performance and advanced protection capability.

Why Choose a Vacuum Circuit Breaker with Integrated Current Transformer?

In traditional medium-voltage switchgear, current transformers are installed separately from circuit breakers, requiring additional bus connections, control wiring, and commissioning procedures. An integrated CT circuit breaker eliminates these extra components by combining protection and measurement functions inside a factory-tested assembly.

• Space Optimization: Integrated CT installation reduces panel footprint and simplifies compact switchgear design.
• Higher Measurement Accuracy: Factory-calibrated current transformers provide stable ratio performance and phase accuracy for protection and metering applications.
• Reduced Installation Cost: Fewer external components mean less wiring, shorter installation periods, and lower maintenance requirements.
• Improved System Reliability: Internal CT connections reduce potential wiring failures caused by loose terminals or incorrect field installation.
• Flexible Protection Configuration: Multiple CT cores support feeder protection, energy monitoring, and revenue metering simultaneously.

Advanced Design for Medium Voltage Power Protection

The integrated structure combines vacuum interrupters, epoxy-resin insulated current transformers, and a spring operating mechanism into a unified protection platform. The vacuum interrupter provides fast and reliable fault current interruption, while the embedded CT cores continuously transmit accurate current signals to protection relays, smart meters, and automation systems.

The epoxy encapsulated CT assembly offers excellent insulation strength, moisture resistance, and mechanical stability under thermal cycling conditions. Each unit undergoes factory testing to verify insulation performance, current ratio accuracy, and mechanical operation reliability before shipment.

With support for protection classes such as 5P10 and 5P20 and metering classes including 0.2S and 0.5S, this solution meets the requirements of demanding applications such as transformer feeders, industrial motor protection, capacitor switching, photovoltaic power plants, and smart grid distribution systems.

Key Features

• Integrated current transformer structure reduces external CT cabinets and secondary wiring complexity.
• Vacuum interruption technology provides fast arc extinction with long electrical service life.
• High-strength epoxy insulation improves environmental resistance and dielectric performance.
• Multiple CT secondary cores support independent protection, measurement, and monitoring circuits.
• Available in indoor fixed type and withdrawable configurations for different switchgear layouts.
• Spring stored-energy operating mechanism ensures stable closing and opening performance.
• Factory testing according to IEC and IEEE standards ensures dependable field operation.

Technical Specifications

Applications of Integrated CT Circuit Breaker

The Current Transformer Circuit Breaker is widely used in medium-voltage electrical systems where accurate current monitoring and reliable protection are required:

• Utility distribution substations
• Industrial power distribution networks
• Transformer feeder protection systems
• Motor control centers
• Solar and renewable energy grid connections
• Capacitor bank switching applications
• Smart grid automation projects

Customization and OEM Support

As a professional medium-voltage switchgear manufacturer, we provide customized solutions according to project requirements, including CT ratio selection, accuracy class configuration, voltage ratings, mounting structures, secondary terminal arrangements, and communication interface requirements.

Our engineering team supports OEM and project-based orders with technical consultation, production testing, and global delivery services to help customers build reliable power distribution systems.

Frequently Asked Questions

Q1: What is the advantage of a Current Transformer Circuit Breaker compared with a standard vacuum circuit breaker?

A: The integrated design combines current measurement and circuit protection in one device, reducing external CT installation requirements, wiring complexity, and commissioning time.

Q2: Can the CT configuration be customized?

A: Yes. CT ratio, accuracy class, burden capacity, and secondary winding configuration can be customized according to protection and metering requirements.

Q3: Which applications require integrated CT circuit breakers?

A: They are commonly used in substations, industrial plants, renewable energy systems, and distribution networks requiring both accurate measurement and fast fault interruption.