SF6-free gas-insulated switchgear for secondary distribution 24kV
Key attributes
| Brand | ROCKWILL |
| Series | RAR |
| Rated voltage | 24 kV |
| Rated frequency | 50 Hz |
| Rated continuous current | 630 A |
| Rated short-time withstand current | 20kA |
Description
ROCKWILL RAR Ring/Plus Air 24kV Series – Ring Main Units
Product Positioning
Suitable for power distribution systems from 6kV to 24kV, the RAR series can be deployed in Ring Main Units (RMU) as well as compact metal-enclosed switchgear. It meets environmental regulations while maintaining the same usage habits as traditional SF₆ equipment.
Environmental Compliance
The series uses dry air as the insulating medium, featuring a Global Warming Potential (GWP) of zero. It fully complies with IEC standards and the EU F-gas Regulation (EU) 2024/573.
Core Technology: Rotary-Limited Mechanism + Linear-Drive Puffer Arc Extinction
ROCKWILL has self-developed the linear-drive three-position puffer arc-extinguishing technology for the RAR series load break switch.
The technology uses a rotary-limited three-position mechanism to directly drive the puffer device inside the arc-extinguishing chamber. At the moment of contact separation, it actively compresses air to form a high-speed airflow, forcing the arc to be extinguished. The three positions (closed / isolated / earthed) are integrated along the same linear drive sequence, resulting in a more compact structure and higher mechanical reliability.
Practical value: Achieves SF₆-like arc-extinguishing performance under dry air (zero GWP), rather than passively relying on the gas's own insulating properties.
Series Breakdown
| Model | Features | Application Scenarios |
|---|---|---|
| RAR Ring Air | Supports combinations of up to 4 modules | Most medium-voltage power distribution switching applications |
| RAR Plus Air | Modularly designed metal-enclosed switchgear, easy to expand, supports higher electrical parameters and various protection relays | Systems requiring expansion or higher performance |
Key Advantages
- Truly Eco-Friendly: Dry-air insulation with zero GWP, F-gas free, recyclable, and fully compliant with EU 2024/573.
- Active Arc Extinction, No Performance Compromise: Rotary-limited three-position mechanism combined with linear puffer arc extinction delivers SF₆-level performance using an Eco-friendly medium.
- Safe & Reliable: Full-direction 20kA/1s internal-arc protection, optional arc suppression, and safe earthing design.
- Compact & Flexible: Three-position linear drive structure reduces transmission components and saves space; supports modular expansion and flexible measurement configurations.
- High Performance: Rated at 24kV/630A, 20kA/3s short-time withstand current, and M2-class mechanical endurance.
- Intelligent Ready: Supports IEC 61850 protocol with integrated online monitoring and diagnostic capabilities.
- Harsh-Environment Adaptable: Operates above 1500m altitude with hermetically sealed anti-pollution components.
Main technical parameters
| Item | Unit | Value |
|---|---|---|
| Rated peak withstand current | kA | 50 |
| Rated duration of short‑circuit | s | 3 |
| Rated short‑time phase‑to‑earth withstand current | kA | 20 |
| Rated peak phase‑to‑earth withstand current | kA | 50 |
| Rated duration of phase‑to‑earth short‑circuit | s | 1 |
| Filling level for insulation and/or switching (abs.) | kPa | 200 |
| Minimum functional level for insulation and/or switching (abs.) | kPa | 180 |
| Rated short‑duration power‑frequency withstand voltage | kV | 50 |
Service Environment
| Item | Specification |
|---|---|
| Air temperature | Maximum temperature: +55℃
|
| Humidity | Monthly average humidity: 95%
|
| Above sea level | Maximum installation altitude: 2500 m or higher |
| Other conditions | Ambient air shall not be obviously polluted by corrosive or flammable gas, vapor, etc. No frequent violent vibration. |
Application Scenarios
- Urban and suburban medium‑voltage ring main distribution networks
- Industrial parks, manufacturing plants and large commercial complexes
- New‑energy power stations: wind farms, solar PV plants and energy storage stations
- Railway, subway, highway and tunnel power supply systems
- Mining, port and coastal projects with high humidity & salt‑fog environments
- Smart grid, data centers and hospital critical power supply projects
Solutions for switchgear
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Rockwill Medium-Voltage SF6-Free Gas-Insulated Switchgear Series – From RMR to REC and RARWithin Rockwill's SF6-free product portfolio, the RMR, REC, and RAR series all adopt gas-insulated, hermetically sealed structures that fully enclose high-voltage live parts in stainless steel tanks, ensuring complete sealing and maintenance-free operation. The three series share a similar modular design philosophy, but differ significantly in insulation medium, technical positioning, voltage coverage, and application scenarios.Core DifferencesIn terms of insulation medium and environmental char
Documentation Resource Library switchgear
FAQ for switchgear
While most domestic Chinese manufacturers utilize similar pure-air RMU architectures, they typically lack puffer-type load break switch (LBS) technology within a sealed tank. Consequently, they rely on Vacuum Circuit Breakers (VCB) to perform switching duties. This approach results in significantly larger dimensions and higher costs for the same voltage rating compared to Rockwill's RAR series.
In contrast, Rockwill’s RAR series utilizes a compact puffer-type LBS design, allowing for a much smaller footprint and superior cost-efficiency. Although currently optimized for secondary distribution, the RAR platform is set to expand into 36kV and higher voltage applications in the near future.
Yes, Rockwill provides comprehensive OEM/ODM programs for the RAR series. However, we are selective in our partnerships; we specifically seek technically capable manufacturers and local partners who possess strong engineering backgrounds and local service capabilities. Our goal is to collaborate with entities that can not only distribute but also technically support our advanced pure-air insulation technology in their regions.
Rockwill’s RAR series is specifically engineered as a pure-air insulated Ring Main Unit (RMU). Based on its unique rotate type puffer-type switch technology, the RAR offers a significantly more compact footprint than competitors.
For instance, at 24kV/1250A, the RAR achieves a unit width of just 325mm—one of the most space-saving designs on the market. Furthermore, the platform is highly scalable; it can be expanded to handle high-capacity applications up to 40.5kV, 4000A, and 40kA, providing a future-proof solution that goes beyond standard secondary distribution needs.
