Eco‑Friendly Ring Main Units Gain Traction as SF₆‑Free Technologies Mature
The medium‑voltage distribution sector is undergoing a significant shift as utilities and industrial users increasingly seek alternatives to sulfur hexafluoride (SF6) – a potent greenhouse gas commonly used as an insulating and arc‑quenching medium in switchgear. Ring main units (RMUs), which are essential for secondary distribution networks, are now available in SF6‑free designs that reduce environmental impact while maintaining reliable performance. These innovations align with global regulatory trends and corporate sustainability goals, making them a preferred choice for new installations and retrofit projects.
A growing number of suppliers in the Asian manufacturing hub are offering SF6‑free RMUs that utilise vacuum interruption and solid or alternative‑gas insulation. The SF6 free ring main unit China segment includes models rated up to 24kV, featuring compact footprints, modular configurations, and integrated protection relays. Without SF6, these units eliminate the need for specialised gas handling equipment during installation and maintenance, simplifying logistics and lowering long‑term operational overhead. They are designed to withstand harsh environmental conditions and comply with IEC 62271‑200 standards, ensuring compatibility with existing network infrastructures.
For applications requiring higher fault‑making capacities and more flexible busbar arrangements, the SF6 free gas insulated switchgear category extends the SF6‑free concept to complete switchgear assemblies. These systems typically replace SF6 with clean‑air mixtures or fluoronitrile‑based gases that have significantly lower global warming potential. They retain the compact advantages of gas‑insulated designs – such as reduced spacing and enhanced protection against pollution – while offering comparable dielectric strength and switching endurance. Such switchgear is well suited for urban substations, wind farms, and data centre power distribution where space is at a premium and environmental compliance is strictly enforced.
Among the most innovative alternatives is solid‑insulated technology, where the main conductive parts are encapsulated in high‑performance epoxy resin. The CKSS 12kV epoxy solid insulated ring main unit supplier – represented by Zhuhai Comking Electric Co., Ltd. – offers a complete range of 12kV solid‑insulated RMUs that are entirely SF6‑free. These units feature a vacuum interrupter for load‑break and fault‑making operations, with the solid encapsulation providing excellent dielectric properties, moisture resistance, and thermal stability. The CKSS series is designed with a modular structure, allowing for flexible combinations of incoming, outgoing, and metering compartments. It also includes visible earth‑switching and interlocking mechanisms to ensure safe operation. Maintenance intervals are extended due to the absence of gas pressure monitoring and leak detection, reducing the total cost of ownership over the equipment’s life.
Zhuhai Comking Electric Co., Ltd. supplies both the SF6‑free ring main units and the solid‑insulated CKSS series, catering to projects that prioritise environmental responsibility without sacrificing operational reliability. All products undergo rigorous type tests, including internal arc classification, temperature‑rise, and mechanical endurance trials. As regulations on SF6 usage tighten in many regions, these SF6‑free solutions are expected to play an increasingly important role in modernising distribution grids, providing a durable and sustainable answer to the evolving needs of power networks worldwide.