| Brand | ROCKWILL |
| Model NO. | 363kV 380kV 400kV 550kV HV SF6 Circuit Breaker supplier |
| Rated voltage | 550kV |
| Rated normal current | 6300A |
| Series | LW55B |
Description
Pioneers in China's GIS tank circuit breaker industry. As the country's first source factory specializing in this field, we boast decades of technical accumulation and continuous innovation — ensuring reliable products while leading the way in Research and Development. Thanks to our outstanding reliability, we've been chosen for numerous major power projects.
LW55B-550/Y4000-50 tank type SF6 circuit breaker is the 3-phase AC transmission equipment.Used in the power system of 550KV, can be realized the controlling, measurement and protection. It is composed of circuit breaker, current transformer and bushings for the wire’s incoming and outgoing. Circuit breaker is a single fracture design, equipped with the first domestic integrated block, high-power hydraulic operating mechanism, all of the hydraulic pipes built-in, no leakage.
This is a product based on new technology research and development, and its performance is at the leading level in the world.
Main Features
Circuit breaker arcing chamber is a single fracture design, simple and reasonable structure, high technical content.
Strong breaking capacity, long contact electrical life(rated short circuit breaking up to 20 times), long service period.
As for the rectifier circuit breaker, except for the bushing unit is packaged independently, arcing unit, hydraulic operating mechanism, current transformer and other components are packaged as a whole unit, without on-site docking and adjustment, easy installation.
Circuit breaker unit is installed on site without opening the chamber, which can be filled the SF6 gas directly, to avoid the intrusion of dust and foreign bodies
There are almost no external pipe for this new type of hydraulic operating mechanism, the possibility of oil leakage is reduced.
When operating the oil pressure, hydraulic operating mechanism is controlled by the pressure switch automatically, can be maintained constantly the rated oil pressure without being affected by ambient temperature, at the same time, the relief valve in the mechanism can be exempted from the risk of overpressure.
After the loss of pressure, hydraulic operating mechanism has the function of not slowing points when the pressure is reconstructed.
The closing resistance of the product can be installed or removed according to the user’s requirements.
Technical Parameters
Among these, some SF6 tank circuit breakers cover non-standard voltage levels including 138kV, 225kV, 230kV, 245kV, 275kV, 330kV, 345kV, 400kV, 756kV, and 800kV (note: 145kV is a standard voltage level, adjusted for accuracy), with a rated short-circuit breaking current of 50kA or 63kA, and we offer customization services.
Specifications |
Unit |
Value |
|
Rated voltage |
kV |
363kV 380kV 400kV 550kV |
|
Rated current |
A |
6300 |
|
Rated frequency |
Hz |
50/60 |
|
Operational altitude |
m |
≤3000 |
|
Operating ambient temperature |
℃ |
-40~40 |
|
Operating pollution class |
Class |
Ⅳ |
|
Wind speed resistance |
m/s |
34 |
|
Aseismatic class |
0.4G (AG4) |
||
Rated short-time withstand current (r.m.s) |
kA |
63 |
|
Rated short-circuit withstand time |
s |
3 |
|
1min rated power frequency withstand voltage (r.m.s) |
Phase to earth |
kV |
740 |
Across isolating distance |
kV |
740 (+318) |
|
Phase to phase |
kV |
740 |
|
Rated lightning impulse withstand voltage (peak) |
Phase to earth |
kV |
1675 |
Across isolating distance |
kV |
1675 (+450) |
|
Phase to phase |
kV |
1675 |
|
Rated SF6 gas pressure (20℃) |
MPa |
0.6 |
|
Opening time |
ms |
20±2 |
|
Closing time |
ms |
70±10 |
|
Closing-Opening time |
ms |
≤50 |
|
During the normal operation and interruption processes of a circuit breaker, SF₆ gas can decompose, producing various decomposition products such as SF₄, S₂F₂, SOF₂, HF, and SO₂. These decomposition products are often corrosive, toxic, or irritating, and therefore require monitoring.If the concentration of these decomposition products exceeds certain limits, it may indicate abnormal discharges or other faults within the arc quenching chamber. Timely maintenance and handling are necessary to prevent further damage to the equipment and to safeguard personnel health.
The leakage rate of SF₆ gas must be controlled at an extremely low level, typically not exceeding 1% per year. SF₆ gas is a potent greenhouse gas, with a greenhouse effect 23,900 times that of carbon dioxide. If a leak occurs, it can not only cause environmental pollution but also lead to a decrease in the gas pressure within the arc quenching chamber, affecting the performance and reliability of the circuit breaker.
To monitor the leakage of SF₆ gas, gas leakage detection devices are typically installed on tank-type circuit breakers. These devices help to promptly identify any leaks so that appropriate measures can be taken to address the issue.
Integral Tank Structure: The breaker's arc quenching chamber, insulating medium, and related components are sealed within a metal tank filled with an insulating gas (such as sulfur hexafluoride) or insulating oil. This forms a relatively independent and sealed space, effectively preventing external environmental factors from affecting the internal components. This design enhances the insulation performance and reliability of the equipment, making it suitable for various harsh outdoor environments.
Arc Quenching Chamber Layout: The arc quenching chamber is typically installed inside the tank. Its structure is designed to be compact, enabling efficient arc quenching within a limited space. Depending on different arc quenching principles and technologies, the specific construction of the arc quenching chamber may vary, but generally includes key components such as contacts, nozzles, and insulating materials. These components work together to ensure that the arc is quickly and effectively extinguished when the breaker interrupts the current.
Operating Mechanism: Common operating mechanisms include spring-operated mechanisms and hydraulic-operated mechanisms.
Spring-Operated Mechanism: This type of mechanism is simple in structure, highly reliable, and easy to maintain. It drives the opening and closing operations of the breaker through the energy storage and release of springs.
Hydraulic-Operated Mechanism: This mechanism offers advantages such as high output power and smooth operation, making it suitable for high-voltage and high-current class breakers.
