| Brand | ROCKWILL |
| Model NO. | 225kV 230kV 245kV 252kV High Voltage gas-insulated metal-enclosed switchgear(GIS) |
| Rated voltage | 252kV |
| Rated normal current | 4000A |
| Rated frequency | 50（Hz） |
| Series | ZF29-252 |
Description：
ZF29-252 gas-insulated metal-enclosed switchgear (referred to as GIS) is used for three-phase AC 50HZ, 220KV power system. The product adopts a common-phase three-station isolated grounding switch structure and modular design, which can meet various wiring methods.
Industry applications：
It is mainly used in power plants, substations, and large industrial and mining enterprises. Divide and combine no-load, load and fault currents, conversion loads, isolation lines, grounding protection and measurement of power transmission and transformation systems.
Features：
The circuit breaker adopts horizontal arrangement, the arc extinguishing chamber adopts a single-break double-acting structure, and the self-energy arc extinguishing principle is equipped with a low-power spring operating mechanism, which effectively reduces mechanical stress, has high mechanical operation reliability, and has a mechanical life of 10,000 times.
Adopt three-station isolation grounding switch structure, mechanical interlocking between isolation and grounding, effectively avoid misoperation, high reliability, and mechanical life of 10,000 times.
Three-station isolation grounding switch and main bus adopt three-phase co-box structure. The sealing surface and bonding surface of SF6 gas are reduced, which greatly reduces the air leakage rate; The three-station isolated grounding switch has no complex external connecting rods and connectors, simple structure and excellent corrosion resistance.
The rated SF6 gas pressure is low, except for the circuit breaker, the other gas chambers are rated at 0.4MPa, which greatly reduces the use of SF6 gas and reduces the greenhouse effect.
Technical parameters：
Dimension：
We have a professional service team.
We have good after-sales.
We can guarantee the quality of our products.
What is the insulation principle of gas-insulated switches?
Insulation Principle:
In an electric field, the electrons in SF₆ gas molecules are slightly displaced from the nuclei. However, due to the stability of the SF₆ molecular structure, it is difficult for electrons to escape and form free electrons, resulting in high insulation resistance. In GIS (Gas-Insulated Switchgear) equipment, the insulation is achieved by precisely controlling the pressure, purity, and electric field distribution of the SF₆ gas. This ensures a uniform and stable insulating electric field between the high-voltage conductive parts and the grounded enclosure, as well as between different phase conductors.
Under normal operating voltage, the few free electrons in the gas gain energy from the electric field, but this energy is not sufficient to cause collision ionization of the gas molecules. This ensures the maintenance of the insulating properties.
