Solid Insulated Ring Main Unit: Leading the Future of Compact Fully Insulated Power Distribution Solutions

The solid insulated ring main unit is a revolutionary product in the modern medium-voltage distribution network field. It uses high-performance solid insulating materials such as epoxy resin to fully cast or seal all high-voltage live parts, including vacuum interrupters, forming one or several independent, fully insulated module units. This design completely abandons traditional SF₆ gas and air insulation, achieving major breakthroughs in safety, environmental protection, and miniaturization of power distribution equipment.

I.Core Insulation Method: Fully Sealed Solid Encapsulation

The core of the solid insulated ring main unit lies in its "fully insulated and fully sealed" structure:

1.Insulation Medium: High-performance solid insulating materials such as epoxy resin or silicone rubber.

2.Encapsulation Process: Through advanced APG (Automatic Pressure Gelation) process, busbars, vacuum interrupters, isolating switches, grounding switches, and other live parts are integrally cast into a solid, fully sealed insulating module.

3.Technical Results: The module exterior forms a grounded metal shielding layer with zero surface potential, truly eliminating the risk of electric shock to personnel and achieving a protection rating up to IP67.

II.Outstanding Product Features

Ultimate Environmental Protection: Completely free of SF₆ gas, eliminating greenhouse gas emissions and potential leakage risks, with a Global Warming Potential (GWP) of zero—truly "green power equipment."

Absolute Safety

Fully insulated and sealed: No exposed live parts in the entire high-voltage circuit, fundamentally preventing personnel electric shock and phase-to-phase short circuits.

Extremely strong environmental adaptability: Unaffected by condensation, pollution, salt fog, altitude, small animals, or other external factors—especially suitable for humid, dusty, and harsh environments.

Flame-proof and explosion-proof: Insulating material is non-combustible solid with no internal arc fault risk, far superior in safety to gas and air insulated equipment.

Compact Structure and Small Size: Due to the much higher dielectric constant of solid insulating materials compared to air, phase-to-phase and ground distances can be greatly reduced, making the cabinet volume 40%-60% smaller than equivalent air-insulated cabinets, significantly saving installation space.

Maintenance-free and Long Lifespan: All high-voltage components are permanently sealed by solid materials, unaffected by oxygen or humidity, with no aging—truly maintenance-free throughout the lifecycle, significantly reducing operation and maintenance costs. The switching part uses vacuum arc extinguishing technology for long electrical life and reliable breaking.

Modular Design and Flexible Expansion: Standardized insulating functional modules can be combined like "building blocks" for easy expansion, flexibly forming various main wiring schemes to meet future load growth needs.

III. Practical Application Scenarios

With its outstanding performance, the solid insulated ring main unit is widely used in scenarios with stringent requirements for safety, environmental protection, and space:

1.Space-Constrained Areas: Narrow distribution rooms in urban core districts, high-end office buildings, commercial centers, and subway stations.

2.Harsh Environments: Coastal areas, chemical parks, mines, windy and sandy plateaus, ships, and offshore platforms.

3.Projects with High Environmental Requirements: National parks, ecological protection zones, and green building projects actively implementing the "dual carbon" strategy.

4.Facilities Requiring High-Reliability Power Supply: Data centers, hospitals, airports, financial centers, etc.