| Brand | ROCKWILL |
| Model NO. | 24kV SF6 Insulated Ring Main Unit（RMU） |
| Rated voltage | 24kV |
| Rated normal current | 400A |
| Rated short circuit breaking current | 16kA |
| Backup Power | NO |
| Series | Sabre |
Product Description
The Sabre Ring Main Unit (RMU) is a high-performance medium-voltage switchgear engineered for secondary distribution networks up to 24kV. Featuring SF6 gas insulation and a sealed stainless steel tank, it offers exceptional reliability with an annual gas leakage rate ≤0.1% and a 30-year service life. Available in non-extensible, extensible, and modular configurations, it supports indoor/outdoor installation and integrates advanced safety, remote monitoring, and flexible expansion capabilitiesideal for utilities, commercial, industrial, and critical infrastructure applications.
Key Features
Superior Safety Protection: Equipped with mechanical interlocks, padlocking facilities, and anti-reflex mechanisms to prevent accidental operation. Fully internal arc-rated (per IEC standards) for maximum operator and pedestrian safety.
SF6 Gas Insulation: Sealed stainless steel tank with SF6 insulation ensures excellent dielectric performance, minimal maintenance, and resistance to harsh environmental conditions.
Long Service Life & Reliability: Robotic welding for structural integrity, fully sealed oil tank (where applicable), and high mechanical endurance components deliver a 30-year life expectancy.
Modular & Extensible Design: Non-extensible, extensible, and modular formats allow on-site expansion without special tools or SF6 gas transfer, adapting to evolving network needs.
Remote Monitoring & Control: Seamless integration with Gemini 3 RTU for real-time monitoring of gas pressure, partial discharge, and switch status. Supports remote operation and predictive maintenance.
Easy Installation & Maintenance: Factory-tested and pre-assembled modules enable fast on-site deployment. Maintenance-free design with accessible components and ≤4-hour single-bay replacement time.
Wide Environmental Adaptability: Operates in -25℃ to 60℃ temperatures, up to 1000m altitude (without derating), and resists pollution, sandstorms, and coastal salt spray.
Comprehensive Protection Options: Offers TLF (time limit fuses) or self-powered relay protection for overcurrent and earth faults.
Smart Grid Ready: Integrates with SCADA systems and supports auto-changeover, auto-sectionalizing, and real-time network condition monitoring for smart grid applications.
Compact & Flexible Mounting: Freestanding or transformer-mounted designs fit limited spaces, with IP54 protection for outdoor use (no kiosk required).
Technical Specifications
Parameter |
Details |
Rated Voltage |
12kV, 15.5kV, 17.5kV, 24kV |
Rated Current |
Up to 630A |
Rated Short-Time Withstand Current |
16kA, 20kA, 21kA (3 seconds) |
Insulation Medium |
SF6 gas (annual leakage rate ≤0.1%) |
Interruption Medium |
Vacuum (vacuum circuit breaker) |
Protection Rating |
Unit: IP54; HV Tank: IP67; LV Control Box: IP54 |
Operating Temperature Range |
-25℃ to 60℃ |
Maximum Altitude (No Derating) |
1000m |
Mechanical Endurance |
Ring switch: M2 (5000 operations); Circuit breaker: M1 (2000 operations) |
Internal Arc Rating |
Up to 21kA for 1 second (unit); 12.5/20kA for 1 second (cable box, optional) |
SF6 Filled Pressure |
0.4~0.5 Bar (G) |
Mounting Options |
Freestanding (indoor/outdoor), transformer-mounted |
Application Scenarios
Urban & Rural Medium-Voltage Distribution Networks: Ideal for branching and distributing power in residential areas, suburban communities, and rural towns. Its compact design fits narrow installation spaces, while low leakage and long service life reduce grid operational costs. The extensible feature supports future network expansion.
Commercial & Public Facilities: Suitable for hotels, shopping centers, hospitals, office buildings, and data centers. Remote monitoring ensures 24/7 stable power supply, and non-exposed live parts plus safety interlocks protect dense human traffic. Fast installation adapts to building construction timelines.
Renewable Energy Integration: Perfect for wind and solar power projects (utility-scale and distributed). It connects renewable energy systems to the grid, stabilizes power output, and works with energy storage systems. Its environmental adaptability withstands desert, plateau, and coastal conditions.
Critical Infrastructure & Transportation: Deployed in airports, tunnels, underground railways, and ports. Complies with strict safety standards (internal arc protection, seismic resistance) and supports remote operations and maintenance to minimize on-site disruptions. Resists harsh environments like salt spray and sandstorms.
Industrial Plants: Powers manufacturing facilities (automotive, mining, cement, petroleum), water/wastewater treatment plants, and industrial parks. Flexible protection options (TLF/relay) adapt to industrial load demands, and modular expansion supports production capacity growth.
