GFX-12 series SF6 standardized ring main unit is a new product developed according to the State Grid Corporation “The standardized Design and Customization Scheme of 12kV Ring Main Unit”，there are two types of cabinets: circuit breaker cabinet and composite apparatus cabinet, it has two forms of side expansion and top expansion, the interface type of the primary and secondary equipment conforms to the standard requirements of the state grid, and its general interchangeability is strong. To achieve any combination and full modularization through the extension of the busbar. The extended busbar is fully insulated and shielded, with dynamic and thermal stability, ensuring high reliability and safety. GFX series standardized ring main unit is mainly used in the State Grid housing project, also suitable for the transformation of power system urban network, distribution power station and load center power station, petrochemical industry, steel and mining industry, general enterprises and institutions, high-rise buildings, etc.
| Project | Unit | Circuit breaker cabinet | Combined electrical cabinet | ||||
| Rated voltage | kV | 12 | |||||
| Power frequency withstand voltage（1min） | Phase to phase and phase to ground | kV | 42 | ||||
| Between open contacts | kV | 48 | |||||
| Lightning impulse withstand voltage | Phase to phase and phase to ground | kV | 75 | ||||
| Between open contacts | kV | 85 | |||||
| Rated peak withstand current | Hz | 50 | |||||
| Rated current | A | 630 | 125 | ||||
| Rated short-circuit breaking current | kA | 20 | 31.5 | ||||
| Rated short-time withstand current | kA/s | 20/4 | / | ||||
| Rated peak withstand current | kA | 50 | / | ||||
| Rated short-circuit making current | kA | / | 80 | ||||
| Rated transfer current | A | / | 1500 | ||||
| Annual leakage rate | ≤0.1% | ||||||
| Arcing test | 20kA 1s | ||||||
| Protection grade | Air box | IP 67 | |||||
| Ring main unit | IP 4X | ||||||
Extension-method | Side expansion, top expansion | ||||||
