EV12 SF6-Free 12kV Ring Main Unit: Solving SF6 Compliance in Medium-Voltage Distribution Switchgear

For distribution engineers specifying medium-voltage switchgear under current and forthcoming SF6 phase-down regulations, the JYDQ Customizable EV12 Eco-friendly Gas Insulated Switchgear 12kV 11kV SF6-free RMU Ring Main Unit Power Distribution Cabinet GIS delivers full 12kV switching and fault protection performance — 25kA short-circuit breaking, 63kA peak making, 25kA/4s short-time withstand, 42kV power-frequency and 75kV lightning impulse dielectric withstand — using nitrogen or dry air at 0.02 MPa gauge. SF6 content is zero. The global warming potential of the insulating gas is zero. No gas management obligations exist across the equipment's service life.

Key Technical Features

Zero SF6 at Near-Atmospheric Pressure

The EV12 insulates with nitrogen or dry air at 0.02 MPa — a fill pressure requiring no pressure vessel certification, no periodic pressure testing, and no specialist gas-handling equipment for maintenance. The 0.02 MPa fill is replenishable from a standard nitrogen cylinder. The sealed IP67 gas tank maintains rated dielectric integrity at zero gauge pressure, eliminating the gas density alarms, automatic lockouts, and emergency callout costs that are routine operational concerns with conventional SF6 RMUs. This zero-pressure operational floor addresses the most common SF6 ring main unit failure mode: dielectric degradation from undetected gas leaks below alarm thresholds. Every gas tank is evacuated and filled to 0.02 MPa using automated filling equipment with dew-point verification at the factory, and each unit undergoes helium leak testing to confirm IP67 integrity before despatch.

Modular C+V Architecture for Targeted Fault Protection

Cabinet C provides a 63kA-peak load break switch for ring-switching operations. Cabinet V provides a 25kA vacuum circuit breaker for fault protection at transformer feeder and sectionalizing positions. Both modules share identical dimensions, gas interfaces, busbar connections, and cable entry arrangements, enabling free mixing in C-C-C-V or C-C-V-V configurations. When ring main network faults propagate beyond the immediate failure zone due to misallocated or absent circuit breaker protection, the C+V modular design resolves this directly: fault interruption is placed exactly where it is needed, without over-specifying the full assembly with all-VCB cabinets.

IP67 Sealed Gas Tank and 1.1Ir Thermal Certification

The gas tank is independently tested to IP67 — dust-tight and protected against temporary water immersion. Sites experiencing seasonal flooding, high groundwater, or coastal salt-spray conditions benefit from a gas tank validated to this ingress standard, where conventional RMU seal performance under sustained environmental exposure is a genuine long-term maintenance concern. The 1.1Ir temperature rise certification (693A continuous, verified in type testing) provides documented thermal margin for the seasonal peak loads and contingency switching currents that are routine in distribution network operation. It is a common assumption that a switchgear unit with a higher current rating must be more reliable — but reliability is determined by how well design margins align with actual operating conditions, not by the rated ceiling.

Applications

• Prefabricated Compact Substation Integration: The EV12 SF6-free RMU serves as the high-voltage switching compartment in prefabricated compact substation assemblies, combining with the distribution transformer and LV panel in a single enclosure. Maintenance-free sealed design reduces lifecycle cost for compact substation operators in urban and commercial distribution projects.
• Ring Main Networks with Under Frequency Relay Coordination: Cabinet V's 25kA vacuum circuit breaker supports protection relay coordination including under frequency relay schemes for islanding detection and load shedding in distributed generation ring networks. RTU/FTU integration enables full remote automation of Cabinet C load break switch positions.
• Renewable Energy Collector Substations — GSU Transformer Interface: Wind and solar farm collector substations connecting a GSU transformer to the 12kV distribution ring require SF6-free primary switchgear for environmental permitting. Remote and unattended renewable energy sites benefit from the EV12 maintenance-free sealed design and zero gas management requirement. All switching, cable termination, and maintenance activities on this medium-voltage equipment are subject to PPE electrical work requirements under applicable national electrical safety regulations. Qualified personnel must use arc-flash-rated protective equipment and follow authorized switching protocols. The EV12 mechanical and electrical interlocking per IEC 62271-200 supports safe switching procedures and prevents inadvertent operation.

Technical Parameters

Commercial Terms

Why Specify the JYDQ EV12?

The JYDQ Customizable EV12 Eco-friendly Gas Insulated Switchgear 12kV 11kV SF6-free RMU Ring Main Unit Power Distribution Cabinet GIS is the specification choice for distribution utilities, EPC contractors, and industrial power engineers who require full 12kV medium-voltage protection with zero SF6 content and zero environmental liability. KEMA-accredited IEC 62271-200 type-test certification covers every configuration. JYDQ manufactures from Zhejiang, China with capacity of 200 sets per month, delivery in 25-40 working days, and full customization to project specification.

FAQ

1. What is EV12 environment-friendly gas insulated switchgear used for?

EV12 is 12kV medium voltage gas insulated switchgear adopting eco-friendly insulating gas instead ofSF6. It is used for receiving, distributing electric energy and circuit fault protection in urban distributionnetworks, box substations and industrial power supply systems.

2. What structural characteristics does EV12 have?

The main switching components are sealed inside a compact metal gas tank. The cabinet occupies smallspace, and the closed structure is not affected by external dust and moisture, maintaining stableperformance in various working environments.

3. What core technical parameters of EV12 can be customized?

We can customize rated current, short-circuit withstand level and main circuit combination scheme. Different configurations can be designed to meet ring-in, ring-out and transformer feeder requirements.

4. What certifications do your EV12 environment-friendly gas insulated switchgears have?

All our EV12 environment-friendly gas insulated switchgears hold CE certification. We can provide CEdocuments and complete technical datasheets for tender submission and customs clearance.

5. What warranty service do you provide for EV12 switchgear?

We provide 10 years warranty for all EV12 gas insulated switchgears. Our technical team provides remote operation guidance and fault analysis support during the whole warranty period.