Description

Product Overview:
This is a core protection and control device designed for medium-voltage (24kV) indoor power systems. It utilizes vacuum interruption technology, features a rated current of 1250 Amperes, and boasts a high short-circuit breaking capacity of 25 kiloamperes (rms). Its “draw-out type” design means the circuit breaker itself is mounted on a withdrawable chassis, facilitating easy maintenance, inspection, and rapid replacement.

Core Applications:

1. Power System Protection (Primary Function):

   • Overload Protection: Automatically trips to cut off power when the line or equipment current exceeds its safe operating value (rated current 1250A) for an extended period, preventing equipment damage from overheating.

   • Short-Circuit Protection: Rapidly (typically within tens of milliseconds) and reliably interrupts severe short-circuit fault currents up to 25kA to prevent equipment destruction, fires, and system collapse. The 25kA breaking capacity is a key performance indicator.

   • Earth Fault Protection (in coordination with relay protection devices): When used with appropriate relay protection devices, it can detect and interrupt line-to-ground short-circuit faults.

2. Electrical Load Control:

   • Normal Switching Operations: Allows safe manual or remote-controlled (via motorized operating mechanism) connection/disconnection of normal load currents up to 1250A. Used for starting/stopping equipment, line switching, and isolation for maintenance.

   • Fault Isolation: After tripping due to a fault, it isolates the faulty section from the rest of the healthy power system, ensuring continued power supply to unaffected areas.

3. System Operation Management:

   • Network Reconfiguration: Used to safely switch between different power supply circuits when changing supply modes or transferring loads.

   • Standby Power Switching (in coordination with automatic transfer schemes): Acts as a critical switching element at points for transferring between main and backup power sources.

Typical Application Scenarios:

• Substations:

  • Incomer/Feeder Cubicles in 10kV / 20kV / 35kV medium-voltage distribution systems.

  • Bus Tie/Section Cubicles connecting two busbar sections.

  • Transformer Incomer/Feeder Cubicles providing protection for transformers.

• Industrial & Mining Plants:

  • Main incoming switches, bus tie switches, or large motor/transformer feeder switches within main distribution rooms or workshop substations of large factories and mines.

• Large Commercial Buildings/Data Centers:

  • Core protection switches within medium-voltage distribution systems of critical facilities like high-rise buildings, hospitals, and data centers.

• Renewable Energy Integration:

  • Protection for medium-voltage output circuits connecting small-to-medium wind farms or photovoltaic power stations.

• Electrified Railways/Urban Rail Transit:

  • Distribution protection within traction substations.

Key Advantages (Based on Parameters and Type):

• High Reliability: Mature and reliable vacuum interruption technology, long electrical and mechanical lifespan, extended maintenance-free intervals.

• High Breaking Capacity: The 25kA short-circuit breaking capacity meets the protection requirements of the vast majority of 24kV distribution systems, ensuring system safety.

• High Current Carrying Capacity: The 1250A rated current is suitable for circuits supplying larger loads.

• Ease of Maintenance: The draw-out design is a major advantage. The breaker can be conveniently withdrawn from the switchgear (to test position or fully outside the cubicle) for inspection, testing, or replacement without disconnecting the main busbars, significantly reducing downtime and improving power supply reliability.

• Enhanced Safety: Clear isolation gap visible upon withdrawal, equipped with reliable safety interlock devices to prevent maloperation.

• Modular Design: Easily integrates into standard mainstream metal-clad withdrawable switchgear like KYN28A-24, KYN61-40.5.

• Environmentally Friendly: Vacuum interruption medium, free of SF6 greenhouse gas.

Summary:
This 24kV, 1250A, 25kA Indoor Draw-out Vacuum Circuit Breaker is a core switching device in modern medium-voltage distribution systems, undertaking critical tasks of protection (overload, short-circuit) and control (switching, isolation). Its robust specifications (especially the 25kA breaking capacity) and convenient draw-out structure make it widely applicable in indoor power distribution installations like substations, industrial plants, and large buildings. It is essential for ensuring the safe, stable, reliable, and flexible operation of power systems, particularly suited for applications demanding high reliability, large-capacity power supply, and convenient maintenance.