XGN-12(TT), as a key part of the automatic power distribution system, is a type of intelligent and eco-friendly switchgear. The XGN-12(TT) type switchgear composes of three functional units, unit V (circuit breaker unit), unit C (load switch unit) and unit F (combined electric apparatus unit). When the system is required to be equipped with multiple units, it can be extended freely on both right and left sides, and arranged at random in accordance with different design schemes, thus satisfying different requirements for configuration.

　　Structurally, each unit consists of the instrument chamber, the operating mechanism and the primary circuit. The instrument chamber can be provided with microprocessor-based protection and other meters and gauges; the operating mechanism is a mechanism designed exclusively for spring operating, and if required, an electric operating mechanism can be equipped additionally; the primary circuit features its automatic pressure gelation (APG) process, through which the busbar, isolating switch and arc extinguish chamber are totally enclosed in epoxy resin together, with the busbar connected with a special-purpose connector.

　　With its advantage of compact structure, full insulation, long service life, maintenance-free, less space occupation, good safety & reliability, and being free from environmental impact, the XGN-12(TT) type solid-insulated switchgear is widely applied to power supply to industrial and civil ring networks and terminals, specially to smaller secondary substations, switching stations, industrial and mining establishments, airports, railways,

　　The XGN-12(TT) type solid-insulated totally enclosed switchgear is produced from the special epoxy resin as insulating material. This type of epoxy resin boasts its

　　excellent performance:

　　Dielectric strength:20~30KV/mm

　　Volume resistivity:(ρv)1×1013~15Ω.m

　　Dielectric loss angle tangent:(tgδ)＜0.004(50Hz)

　　1. Able to endure a heat as high as above 200℃, and to keep a good insulation property even at a high level of temperature;

　　2. Stable chemical property: excellent resistance to alkali, acid and solvent, as well as good resistance to temperature aging and radiation aging;

　　3. With a coefficient of thermal conductivity of 80×10-2~100×10-2W/m.k, it contributes to heat dispersion;

　　4. Having strong cohesion for any substances, close molecular structure and high mechanical strength, it plays a protective role for switchgears.

　　5. With a curing shrinkage as low as 1%~2% generally and a coefficient of liner expansion as low as 6×10-5/℃ generally, it allows switches to have a stable dimension

　　and a small internal stress for fear of a cleavage in any circumstances.

　　1. An electric operating mechanism is optional not only for the main switch but also for the isolating switch and ground switch, as is a profound backup for the automation

　　and intelligentization of the electric distribution network;

　　2. The totally sealed design of live parts allows an integral realization of the fully insulated and totally sealed structure, with a degree of protection of IP67, which means

　　the unit can function normally for a short time even under water.

　　3. The open/close positions of switches can be seen clearly from the sight glass;

　　4. The modular design with segregated phases facilitates combination of units and expansion of loops, and enhances insulating property.

　　5. An absolute eco-friendly structure, with no SF6 being used for gas insulation and free from pollution forever;

　　6. The ingenious design of mechanical and electric interlocks can meet the requirements for the ?five preventions? , thus ensuring the safety of personnel and equipment;

　　The delicate outline and pastel shades bring users a sensuous enjoyment.

　　1. The disuse of SF6 in the solid-insulated switchgear avoids any explosive accidents arising from deterioration in insulating property and arc-extinguishing capability, which is attributable to insufficient gas pressure in the SF6 ring network cabinet.

　　2. The adoption of an explosion-proofing vacuum arc-extinguishing chamber, in which the solid insulating layer provides the switch with further protection, ensures the safety of equipment and personnel.

　　3. The modular design of the segregated structure between phases avoids any accidents arising from short circuit between phases or between multiple loops.

　　4. The “five-prevention interlock” between the main circuit switch, isolating switch, ground switch and cabinet door ensures the safety of repairmen and maintenance personnel.

　　5. The open/close positions of all phases of switches can be seen clearly from the sight glass, thus enhancing the safety of personnel during operation, examination and repair.

　　6. The high glass temperature of epoxy resin guarantees that the insulating property of epoxy resin and silicon rubber would not deteriorate when suffering a high temperature.

　　7. The adoption of flexible fillers between the epoxy resin insulating layer and the primary conductor of switches eliminates the stress caused by expansion with heat and contraction with cold, thus avoiding the occurrence of cracks.

　　8. The adoption of all-round reversing gear with the operating mechanism improves the reliability of the operating mechanism.

　　9. A degree of protection as high as IP67 allows the solid-insulated switch to function normally even under water.

　　10. The switch position indication is fixed to the main shaft, thus enhancing the correctness of the indication.