10kV side expansion bus coupler (lateral bus connector) is a critical component used in European-style ring main units, cable branch boxes, and other power distribution equipment to extend bus interfaces and enable multi-circuit connections.
Product Overview
The 10kV side-extension bus coupler is a fully insulated, separable bus extension component designed for 10kV (compatible with 15kV system voltage class) power distribution systems. Manufactured via integral injection molding of ethylene propylene diene monomer (EPDM) rubber, it features full insulation, complete sealing, and a touchsafe construction. It is primarily used for bus-side extension on European-style ring main units to extend and expand bus interfaces, providing connection points for additional outgoing circuits without requiring modification of the existing bus structure.
Product Features
Insulation and Electrical Performance
Manufactured via integral injection molding of premium EPDM rubber, the component exhibits excellent insulation performance and is capable of withstanding the operating voltage of a 15kV system. Power-frequency withstand voltage and impulse withstand voltage performance comply with industry standards, ensuring safe electrical connections.
An integrated semiconductive shielding layer provides uniform electric field distribution, eliminating the risk of partial discharge caused by electric field concentration and enhancing long-term operational reliability.
The fully sealed structure provides IP67 protection, effectively preventing the ingress of moisture, dust, and oil contaminants. Suitable for harsh environments including high-humidity and high-dust conditions, ensuring stable bus connections.
Installation and Construction Characteristics
The separable plug-in design enables convenient installation without special tools. The component connects directly to the bus interface of European-style ring main units via plug-in coupling, allowing rapid installation, significantly reducing installation time and construction costs.
Standardized interfaces are compatible with the bus interfaces of 10kV European-style ring main units and cable branch boxes, offering strong universality and excellent interchangeability to facilitate equipment expansion and retrofitting.
The fully insulated, touchsafe construction ensures that the coupler surface is at ground potential after installation, with no exposed live parts, eliminating the need for additional insulation protection and ensuring the safety of operations and maintenance personnel.
Environmental and Weather Resistance
Excellent weather resistance allows adaptation to wide-temperature environments from -40°C to +90°C. Rubber elasticity and insulation performance do not degrade at high or low temperatures, with no risk of cracking, embrittlement, or deformation. Suitable for both indoor and outdoor applications.
Anti-aging, UV-resistant, and ozone-corrosion-resistant properties provide a service life of over 20 years with maintenance-free operation, reducing long-term operations and maintenance costs.
Chemical corrosion resistance enables adaptation to harsh environments including high humidity, heavy dust, salt spray, and mild acid-alkali conditions, with no risk of corrosion or degradation. Suitable for industrial and mining enterprises, coastal regions, and similar applications.
Mechanical and Safety Characteristics
High mechanical strength of the rubber material, including tear resistance and tensile resistance, allows the component to withstand mechanical stresses encountered during construction and operation, with no risk of damage or cracking.
Features anti-misoperation and electric shock prevention design. Upon completion of installation, the unit is automatically grounded, and the coupler surface is touchsafe, ensuring high safety for distribution applications where personnel contact is frequent.
Compact structure and small footprint are suitable for installation in confined spaces, requiring no additional internal equipment space.
Technical Parameters
| Parameter Category | Item | Technical Specification |
| Electrical Parameters | System Voltage | 10kV AC (compatible with 15kV voltage class) |
| | Rated Current | 630A (customizable upon request) | |
| | Power-Frequency Withstand Voltage (5 min) | 42kV, no breakdown | |
| | Impulse Withstand Voltage (peak) | 95kV, no breakdown | |
| | Insulation Resistance | ≥1000MΩ | |
| | Partial Discharge Level | ≤5pC (at 1.5 times rated voltage) | |
| Structural and Material Parameters | Body Material | Ethylene Propylene Diene Monomer (EPDM) rubber |
| | Compatible Interface Specification | Standard European-style ring main unit bus interface | |
| | Protection Rating | IP67 | |
| | Construction Type | Fully shielded separable side-extension bus coupler | |
| Environmental Parameters | Operating Altitude | ≤2000m (high-altitude customization available) |
| | Ambient Temperature | -40°C to +90°C (operating), -40°C to +70°C (storage) | |
| | Relative Humidity | ≤100% (non-condensing) | |
| | Seismic Rating | Grade 8 | |
| Applicable Standards | GB/T 12706, IEC 60840, GB/T 11022 General Requirements Common to High-Voltage Switchgear and Controlgear Standards |
Scope of Application
Applicable Voltage Class: 10kV AC power systems.
Applicable Scenarios:
Bus-side interface extension on European-style ring main units and cable branch boxes;
Bus circuit capacity expansion in compact substations and switching stations;
10kV distribution system retrofitting in urban power distribution networks, industrial and mining enterprises, and commercial buildings;
Bus extension connections for both indoor and outdoor applications;
Distribution scenarios with frequent personnel contact where high safety standards are required.
Functional Purpose: To provide bus interface extension for 10kV European-style power distribution equipment, enabling the connection of additional outgoing circuits without modifying the existing bus structure, thereby ensuring safe and stable operation of the distribution system and avoiding outage and construction risks associated with bus modification.
Operating Conditions
Normal Operating Conditions
Altitude: ≤2000m;
Ambient Temperature: -40°C to +90°C, without rapid temperature fluctuations;
Relative Humidity: ≤100% (non-condensing);
Environmental Conditions: free from corrosive gases, flammable and explosive media, and severe vibration or shock;
Installation Method: plug-in installation, connecting directly to the bus interface of European-style ring main units; installation space must satisfy the dimensional requirements of the bus coupler.
Special Operating Conditions (customization required)
Altitude exceeding 2000m;
Ambient temperature outside the range of -40°C to +90°C;
Severely polluted, salt spray, or chemically corrosive environments;
High-vibration or high-shock operating conditions;
Non-standard interfaces or special current rating requirements.
Installation and Maintenance
Installation Requirements
Before installation, inspect the product appearance to verify that the bus coupler is free of cracks, damage, and voids, and that all accessories are complete and undamaged.
Clean the ring main unit bus interface in accordance with process requirements, removing oil contaminants and dust to ensure the surface is dry and clean.
Insert the bus coupler directly into the bus interface via plug-in connection, adjusting the position to ensure reliable connection and proper seating.
After installation, verify that the bus coupler connection is secure with no looseness or misalignment, that the grounding connection is satisfactory, and confirm correct installation before completing the process.
Maintenance Requirements
Periodically inspect the bus coupler appearance for cracks, damage, discharge marks, and contamination buildup; verify that the connection between the bus coupler and bus interface is tight with no looseness or gaps.
Periodically test the insulation resistance of the bus coupler to ensure performance meets requirements and to identify potential hazards in a timely manner.
Clean the bus coupler surface to remove accumulated dust and contamination, maintaining a dry and clean surface and protecting against oil and chemical corrosion.
If abnormalities such as cracks, damage, discharge, or out-of-specification insulation resistance are detected, the bus coupler must be replaced promptly. Continued operation in a degraded condition is strictly prohibited.
Precautions
The product must be installed, commissioned, and maintained by qualified personnel holding high-voltage electrical installation credentials. Operation by unqualified personnel is strictly prohibited.
The product must be used in conjunction with the corresponding specification of 10kV European-style power distribution equipment. Mismatching equipment of different specifications is strictly prohibited, as this will result in connection failure and safety incidents.
Unauthorized disassembly or modification of the product is prohibited, as this will void the warranty and safety assurance. Forcible stretching or cutting of the bus coupler is strictly prohibited to prevent damage to the rubber material.
During installation, ensure that the bus coupler is fully seated and the connection is reliable to prevent degradation of electrical performance due to poor contact.
During storage, place the product in a dry, ventilated, and cool environment, away from direct sunlight, high temperatures, humidity, and compression. Contact with sharp objects that could damage the bus coupler is strictly prohibited.
During operation, periodically inspect the condition of the bus coupler; prevent external mechanical compression or impact forces on the bus coupler to avoid damage or sealing failure.
Applicable Standards and Certifications
International Standard: IEC 60840 Test Methods and Requirements for Power Cables with Extruded Insulation and Their Accessories for Rated Voltages above 30kV (Um=36kV) up to 150kV (Um=170kV);
National Standards: GB/T 12706 Power Cables with Extruded Insulation and Their Accessories for Rated Voltages from 1kV (Um=1.2kV) up to 35kV (Um=40.5kV); GB/T 11022 Common Specifications for High-Voltage Switchgear and Controlgear Standards;
The product has passed type testing by the National Wire and Cable Quality Supervision and Inspection Center and complies with national electric power industry standards.
Appendix: Product Dimensional Diagram
