Outdoor High Voltage SF6 Live Tank Circuit Breaker

I. Product Overview
The LW30-252/T4000-50 outdoor high voltage SF6 live tank circuit breaker is the latest generation of 252kV SF6 disconnecting device independently developed by our company on the basis of our years of experience in designing SF6 products. It is China's first self-energy circuit breaker equipped with full spring mechanisms and passing 50kA rated short circuit breaking current test. It is applicable to the control and protection of 252KV power transmission and distribution system and it is also able to serve as an interconnecting circuit breaking device. Its features are described below.

1. Self-energy Type Arc Extinguishing, Excellent Breaking Performance
The principle of self-energy type arc extinguishing is as follows. The SF6 gas inside the air cylinder is heated by the arc energy. Its volume expands and its pressure increases, which increases the arc blowing pressure of the circuit breaker when the arc current crosses zero. This arc extinguishing method reduces the operating power required, thus reducing the burden on the operating mechanism, while ensuring good breaking capacity.Our product is equipped with an improved self-energy arc extinguishing chamber. With no breaking dead zone, it has excellent breaking performance in all breaking sections. The breaking times at 50kA and full capacity is more than 20 times.

2. Full Spring Mechanism
The LW30-252/T4000-50 outdoor high voltage SF6 live tank circuit breaker is equipped with the full spring mechanism developed by our company. There is no risk of oil or air leakage. Compared with other spring operating mechanisms which use ratchet and pawl for speed reduction and transmission, our spring mechanism adopts worm gear and chain drive. Hence, there is no impact and the transmission is stable with high reliability. In addition, the tripping system of our spring mechanism adopts three-level force reduction mechanism which has smaller tripping force, more sensitive and reliable operation, as well as smaller impact in compared with two-level force reduction mechanism.

3. Modular Structure
The circuit breaker and the operating mechanism are designed in line with the modular design concept. This simplifies structure and reduces interactions between each part, thus greatly reducing potential hazards. The modular structure also facilitates onsite repair and maintenance.

4. High Quality Components
All important components are imported. For example, the opening and closing spring of the circuit breaker is imported from Japan and all bearings are from Germany or Japan. Key components are processed by the machining center and the CNC wire cutting machine, so as to ensure the machining precision of the components. Excellent components ensure reliable performance of the product. The mechanical life of our circuit breaking device reaches 6000 times or more.

5. Beautiful Appearance, Wide Adaptation
The body part of this product adopts support porcelain bushing and hot dip galvanized bracket. The operating mechanism box is made of high quality stainless steel. The whole product is beautiful in appearance and it has strong corrosion resistance.The rated short circuit breaking current of our product still reaches 40kA when it is used in the low-temperature region of minus 40 degrees. All transmission parts adopt wide-temperature-range lubricating grease, making the circuit breaker applicable to areas with various harsh natural conditions.

II. Comparison with Similar Products at Home and Abroad
The mainstream products of major domestic 252kV circuit breaking device manufacturers adopt puffer type arc extinguishing. They are equipped with hydraulic or pneumatic operating mechanism. Gas leaks, oil spills, pressure relief and other issues exist. The rated short circuit breaking current of the 252kV disconnecting device which are newly developed by major domestic manufacturers and equipped with full spring mechanism only reaches 40kA. Even adopting self-energy arc extinguishing and full spring mechanism, the value is still the same. However, our LW30-252/T4000-50 outdoor high voltage SF6 live tank circuit breaker, adopting self-energy arc extinguishing and full spring mechanism, has a rated current of 4000 or 3150 A and a rated short circuit breaking current of 50kA. These parameter values reach domestic leading level. In terms of electrical life, mechanical life and other main technical indexes, our product is also comparable with similar products from world well-known manufacturers.

Related Names
High Voltage Switching Device | Thermal Breaker | Short Circuit Protection Breaker