| Brand | ROCKWILL |
| Series | RMR，REC |
A compact gas-insulated ring main unit for primary distribution networks, using G3 / clean gas insulation instead of SF6. Sealed for life, maintenance-free, and engineered for 12–40.5kV primary rings.
A ring main unit where the live parts are enclosed in a sealed tank filled with G3 clean gas, built for primary distribution — the upstream network feeding secondary rings.
A primary gas insulated RMU uses G3 (fluorinated ketone) clean gas for phase-to-earth and phase-to-phase insulation, paired with a sealed vacuum interrupter for current breaking. Unlike traditional SF6 RMUs, G3 has a global warming potential near zero. The sealed tank makes it immune to pollution, dust and humidity, making it ideal for primary networks in industrial, renewable and urban environments where compactness and reliability matter.
G3 (3M Novec) insulation with near-zero GWP — the environmentally responsible alternative to SF6.
Fully sealed tank means no gas top-ups, no maintenance, and immunity to external pollution.
Gas insulation allows a much smaller footprint than air-insulated equivalents — ideal for space-constrained primary stations.
G3 clean gas replaces SF6 — near-zero GWP, no F-gas reporting burden.
Sealed tank ignores dust, humidity, salt fog and industrial pollution.
No gas-density monitoring or top-ups; vacuum interrupters sealed for life.
Type-tested to IEC 62271 with proven G3 technology in service worldwide.
12kV, 24kV, 33kV and 40.5kV classes for primary distribution networks.
Built to your ring layout and brand, with IEC 62271 documentation for tenders.
Representative values; the certified datasheet is prepared on request — contact us.
| Parameter | Typical value |
|---|---|
| Rated voltage | 12kV / 24kV / 33kV / 40.5kV |
| Power frequency withstand | 28kV / 50kV / 70kV (by class) |
| Lightning impulse withstand | 75kV / 125kV / 170kV (by class) |
| Rated frequency | 50 / 60 Hz |
| Insulation medium | G3 clean gas (fluorinated ketone) — SF6-free, near-zero GWP |
| Breaking device | Sealed vacuum interrupter |
| Busbar rated current | 630A / 1250A (up to 2000A on request) |
| Rated short-time withstand | 20kA / 25kA for 3s |
| Configuration | 2 ring incomers + transformer feeder (switch-fuse / VCB) |
| Standard | IEC 62271-1, -102 / -103 |
It is a gas-insulated ring main unit built for primary distribution networks, using G3 clean gas instead of SF6 for compact, sealed, low-maintenance protection.
No. G3 (3M Novec fluorinated ketone) is a clean gas with near-zero global warming potential. It delivers comparable dielectric performance to SF6 without the environmental penalty.
Gas-insulated RMUs are sealed and compact — immune to pollution, humidity and dust, with a smaller footprint than air-insulated equivalents. This matters in primary stations where space and reliability are critical.
Yes. We manufacture primary gas insulated RMUs under OEM/ODM with your nameplate and IEC 62271 documentation.
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