EFX-12 series environmentally-friendly gas(dry air) standardized ring main unit is a circuit breaker cabinet developed according to the State Grid Corporation “The standardized Design and Customization Scheme of 12kV Ring Main Unit”，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. EFX-12 series ring main unit does not need SF6 gas, reduces the damage to the atmosphere, with significant ecological benefit, it is the future direction of environmentally-friendly electrical equipment.
EFX series standardized ring main unit is mainly used in the housing and distribution projects of the State grid, and is also suitable for the transformation of power system urban network, power distribution 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 | |||||
| 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 frequency | Hz | 50 | |||||
| Rated current | A | 630 | |||||
| Rated short-circuit breaking current | kA | 20 | |||||
| Rated short-time withstand current | kA/s | 20/4 | |||||
| Rated peak withstand current | kA | 50 | |||||
| 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 | ||||||
