The mechanical and electrical core of modern metal-clad switchgear. Delivering flawless short-circuit interruption, precision chassis tracking, and mechanical endurance up to 30,000 operations.
An Indoor Vacuum Circuit Breaker (VCB) is the primary protection device housed inside medium-voltage metal-clad switchgear (such as the KYN28 or KYN61 series). It utilizes high-vacuum interrupters to rapidly and safely extinguish electrical arcs caused by massive short-circuit fault currents.
Central Type Panels
Mounted on a precision-engineered chassis truck equipped with high-conductivity silver-plated tulip contacts. Designed to be smoothly racked into the "Service" and "Test" positions within central-type switchgear (KYN series).
Compact Panels & RMU
A stationary unit hard-bolted to the switchgear framework. Lacking a chassis and tulip contacts, it significantly reduces the overall depth of the panel, making it ideal for compact secondary substations (XGN series) and Ring Main Units.
The vacuum interrupter and main conductive parts are cast entirely in solid APG epoxy resin. This completely shields the interrupter from dust, condensation, and mechanical impact, achieving a truly maintenance-free primary circuit. Highly recommended for heavy pollution or high-humidity areas.
The vacuum interrupter is housed within an insulated polymer tube. This traditional design provides excellent air convection cooling, making it highly effective for heavy current applications (up to 4000A) while maintaining a lower cost profile for clean indoor environments.
| Parameter | Unit | 12kV VCB Series | 24kV VCB Series | 36kV / 40.5kV Series |
|---|---|---|---|---|
| Rated Voltage | kV | 12 | 24 | 40.5 |
| Rated Current (Max) | A | 630 / 1250 / 3150 / 4000 | 630 / 1250 / 3150 | 1250 / 2500 / 3150 |
| Rated Short-Circuit Breaking Current | kA | 20 / 25 / 31.5 / 40 / 50 | 20 / 25 / 31.5 | 25 / 31.5 |
| Short-Time Withstand Current (3s) | kA | 20 / 25 / 31.5 / 40 / 50 | 20 / 25 / 31.5 | 25 / 31.5 |
| Standard Phase-to-Phase Distance | mm | 150 / 210 / 275 | 210 / 275 | 300 / 400 |
| Mechanical Endurance | Ops | 20,000 to 30,000 Operations (M2 Class) | ||
| Operating Mechanism Type | - | Spring-Charge (Motorized/Manual) or Permanent Magnetic | ||
The phase-to-phase distance (e.g., 150mm, 210mm, 275mm) represents the spacing between the centers of the three poles (phases). This is a critical dimension because it must precisely match the spacing of the static contacts (spout boxes) within your switchgear cabinet (like KYN28). A 210mm distance typically fits an 800mm wide cabinet, while 275mm fits a 1000mm cabinet.
Yes, as an OEM manufacturer, we can fully customize the length, diameter, and silver-plating thickness of the tulip contacts and contact arms to ensure they perfectly engage with your specific switchgear design and maintain optimal current carrying capacity without overheating.
Absolutely. All our withdrawable VCB chassis are equipped with strict mechanical interlocks designed to comply with the "Five Preventions" safety standards. For instance, the breaker cannot be racked in or out while it is in the closed position, and it cannot be closed unless it is securely locked in either the Test or Service position.
Submit your requirements on a business day, and our engineers will provide an initial OEM proposal within 24 hours.
We supply complete medium & high voltage solutions, including:
• Air Insulation Series
• Gas Insulation Series
• Switching Devices
• Instrument Transformers
