Products
High Quality Ring Main Unit Components for Reliable Power Distribution
- View as
33KV Medium Voltage Circuit Breaker Operating Mechanism
The KDCM-40.5/630-20-X series 33KV Medium Voltage Circuit Breaker Operating Mechanism is a critical component in medium-voltage power distribution system, as a circuit breaker actuator which governs the opening and closing of the main circuit breaker. Manufactured by Cotenele, a professional China supplier, this operation mechanism utilizes a unique dual-spring system:a tension spring for closing and a compression spring for opening,This dual-spring system can ensure reliable operation of circuit breaker.
22kV Vacuum Circuit Breaker with Load Break Switch
Cotenele International Trade (Wenzhou) Co., Ltd., a leading Chinese manufacturer, produces the 22kV Vacuum Circuit Breaker with Load Break Switch, a core switching element in ring main units (RMUs), typically used to achieve safe and reliable power control in medium-voltage distribution networks. Its three-position load break switch integrates visual isolation and grounding functions, primarily used to interrupt load current under normal operating conditions. In modern power distribution systems covering voltage levels from 6kV to 40.5kV, this load break switch is a crucial core component of ring main unit switchgear.
22KV Medium Voltage Switchgear Electrical Mechanism
The KDCM-24D/630-20 series 22KV Medium Voltage Switchgear Electrical Mechanism from Cotenele International Trade (Wenzhou) Co., Ltd combines tension and compression springs to ensure reliable operation, with a mechanical endurance exceeding 10,000 operations. Supporting both manual and electric operation, the mechanism features anti‑misoperation design and complies with GB 1984 - 2014 (high-voltage AC circuit breakers) and GB/T 1985‑2023 (high-voltage AC disconnectors) standards.
11KV MV Panels Vacuum Circuit Breaker Isolating Switch
Cotenele International Trade (Wenzhou) Co., Ltd is a leading China manufacturer and exporter of 11KV MV Panels Vacuum Circuit Breaker Isolating Switch for eco-friendly medium-voltage switchgears (MV panels, RMUs, GIS). Our products provide high reliability, operational safety, and low maintenance for industries such as power, railway, petrochemical, municipal construction, and renewable energy.
11KV MV Switchgear Circuit Breaker Isolation Mechanism
Cotenele, a professional manufacturer in China, produces the 11kV MV Switchgear Circuit Breaker Isolation Mechanism, a core component of ring main units. These mechanisms are designed to provide safe, high-speed protection and reliable electrical isolation. We specialize in providing medium-voltage switchgear and ring main unit solutions for power, railway, petrochemical, municipal, and renewable energy projects.
11KV Electrical Operation Mechanism for Circuit Breaker Isolating Switch
Cotenele, a professional China manufacturer, provides 11KV Electrical Operation Mechanism for Circuit Breaker Isolating Switch, a crucial component of environmentally friendly switchgear and ring main units (RMUs) widely used in power distribution systems. These core components of RMUs and environmentally friendly switchgear are critical to power grid reliability. Modular mechanism solutions can significantly improve the safety, space utilization, and lifespan of power equipment.
Common Ring Main Unit Components
Primary Circuit Components
- Vacuum Circuit Breaker (VCB)
- Load Break Switch (LBS)
- Disconnector (Isolator)
- Earthing Switch
Protection and Measurement Components
- Current Transformer (CT)
- Voltage Transformer (VT)
- Fuses
- Surge Arrester
Control and Indication Components
- Operating Mechanism
- Interlocking System
- Voltage Presence Indicator
- Secondary Terminal Blocks
Insulation and Support Components
- Insulators
- Bushings
- Solid or Gas Insulation Structural Parts
Key Switching Devices in RMU Systems
Vacuum Circuit Breaker (VCB)
A Vacuum Circuit Breaker uses vacuum as both the insulating and arc-extinguishing medium. Its core contacts are sealed inside a vacuum interrupter. When the moving contact separates from the fixed contact, an electric arc is generated. In a vacuum environment, the arc rapidly disperses and is extinguished as the metal vapor condenses. The arc is naturally extinguished at current zero, and dielectric strength is quickly restored.
Application: VCBs are characterized by high breaking capacity, frequent operation capability, and low maintenance requirements. They are widely used in 3–10kV distribution systems for protection and control of power lines and equipment. They can interrupt both normal load current and short-circuit fault current, providing overload, short-circuit, and under-voltage protection. VCBs can be installed in both withdrawable and fixed-type switchgear.
Application: VCBs are characterized by high breaking capacity, frequent operation capability, and low maintenance requirements. They are widely used in 3–10kV distribution systems for protection and control of power lines and equipment. They can interrupt both normal load current and short-circuit fault current, providing overload, short-circuit, and under-voltage protection. VCBs can be installed in both withdrawable and fixed-type switchgear.
Load Break Switch (LBS)
A Load Break Switch is a switching device located between a disconnector and a circuit breaker. It is equipped with a simple arc-extinguishing mechanism and can make and break normal load current and overload current, but it cannot interrupt short-circuit fault current. After disconnection, a visible isolation gap is usually formed.
Application:LBS is used for switching electrical circuits under normal load conditions. Since it cannot interrupt fault currents, it is usually used together with high-voltage fuses, which provide short-circuit protection. It is widely used in 10kV and below distribution systems for transformer control.
Application:LBS is used for switching electrical circuits under normal load conditions. Since it cannot interrupt fault currents, it is usually used together with high-voltage fuses, which provide short-circuit protection. It is widely used in 10kV and below distribution systems for transformer control.
Disconnector
A disconnector has a simple structure. Its main feature is a clearly visible isolation gap after opening, ensuring that electrical equipment is safely isolated from the power source during maintenance. It has no arc-extinguishing capability and must not be operated under load conditions.
Application:It is mainly used during maintenance or inspection to ensure reliable isolation between equipment and the energized system, providing a clear and visible safety separation point.
Application:It is mainly used during maintenance or inspection to ensure reliable isolation between equipment and the energized system, providing a clear and visible safety separation point.
Switchgear Comparison
| Item | Vacuum Circuit Breaker | Load Break Switch | Disconnector |
|---|---|---|---|
| Arc-Quenching Device | Vacuum interrupter | Simple arc-extinguishing device | No arc-extinguishing capability |
| Making/Breaking Capacity | Can interrupt load and short-circuit currents | Can interrupt load current only | Cannot interrupt load current |
| Primary Purpose | Protection and control | Load switching | Isolation |
| Disconnection Visibility | No visible disconnection | Usually visible disconnection | Clear visible isolation gap |
Operating Mechanism
The operating mechanism is an essential execution unit in Ring Main Unit components, responsible for driving the opening and closing operations of main switches and earthing switches. It converts mechanical, electromagnetic, or stored spring energy into precise mechanical motion to ensure reliable switching performance.
Common Types of Operating Mechanisms
- Spring-Operated Mechanism:Most widely used type, storing energy in a spring for fast and reliable operation.
- Magnetic Mechanism:Simple structure, high reliability, and low maintenance requirements.
- Manual Mechanism:Used as backup or low-cost solution for basic distribution systems.
RMU Unit Types and Operating Mechanisms
| RMU Type | Unit Name | Main Switching Component | Operating Mechanism Type | Description |
|---|---|---|---|---|
| C-Unit | Load Break Switch Unit | Load Break Switch (LBS) | Spring-Operated Mechanism | Single spring operation; optional motorization available |
| F-Unit | LBS-Fuse Combination Unit | LBS + Fuse | Spring Mechanism with Trip Function | Dual spring system; fuse striker trip protection |
| V-Unit | Vacuum Circuit Breaker Unit | Vacuum Circuit Breaker (VCB) | Spring / Magnetic Actuator | Interrupts fault current; works with protection relays |
| D-Unit | Busbar Riser Unit | No main switch | None | Used for busbar connection between sections |
Withdrawable Switchgear vs RMU
| Item | Withdrawable Switchgear (KYN28) | Ring Main Unit (RMU) |
|---|---|---|
| Main Switching Component | Withdrawable Vacuum Circuit Breaker | Load Break Switch + Fuses or fixed VCB |
| Disconnector Function | Replaced by withdrawable truck | Integrated 3-position switch |
| Fuses | Less common | Common for transformer protection |
| Structure | Withdrawable design | Fixed compact design |
| Protection Function | Advanced protection systems | Simpler fuse-based protection |
| Size | Larger | Compact |
