LW58A-550 Dead Tank SF6 Circuit-Breaker

///LW58A-550 Dead Tank SF6 Circuit-Breaker

LW58A-550 Dead Tank SF6 Circuit-Breaker


  1. Product introduction:

LW58A-550 GCB is one of AC transmission switchgear, which is composed of circuit breaker, current transformer, bushing. And it can control, measure, protect power system of 550kV.


  • The domestic first high power spring operation mechanism of circuit breaker , which has the small volume and is safe and stable, free of maintenance. high reliable and conform to oil free and gas free requirements for operation mechanism;
  • Interrupter unit adopts shunt capacitor to balance the voltage between open contacts It improves short line fault breaking capability;
  • Excellent insulation level and low partial discharge. The only company in the industry that can achieve: under the 80% power-frequency withstand voltage (80%×740kV = 592kV), the partial discharge of intervals is lower than 5pC, the partial discharge of the insulator is lower than 3pC. It’s better than the IEC standard that the partial discharge should be lower than 5pC under 1.2 times phase voltage (1.2×550/√3 = 381kV);
  • Partial discharge and lightning impulse voltage withstand test before delivery; The hidden trouble of discharge must be eliminated and ensure the reliability of  products;
  • The insulator quality is stable and reliable. The insulator pouring process reaches the international advanced level;
  • High parametric: All product technical parameters are the highest standard in the industry;
  • Arrangement of circuit breaker is horizontal, it’s convenient for overhauling and emergency maintenance; it also will make lighter impact to the ground;
  • Flange surface adopts double sealing ring structure, inner ring sealing gas, and its gas leakage rate is lower than IEC standard. Its outer ring prevents water and impurities from getting inside thus to improve safety and reliability;
  1. Application environment
  2. Installation site: outdoor;
    2. Ambient temperature:
    Maximum temperature: +55
    Minimum temperature: -40
    Maximum daily temperature difference: 32 K

          3. Altitude: 2500m;
    4. Sunshine intensity: 1000 W/m2;
    5. Pollution class: Class III/IV;
    6. Ice thickness: 10 mm/20 mm;
    7. Wind speed/ wind pressure: 34m/s ( equals cylinder surface 700 Pa);
    8. Humidity:
    Average of daily relative humidity: 
    Average of monthly relative humidity: 
    9. Seismic resisting ability: 9 degree;

III.      Product usage

LW58A-550  GCB is one of the latest generation of switch equipments developed by Shanghai Sieyuan Electric Co,. Ltd. It obtains users’ trust because of its advanced design and reliable property. At present, this whole set of equipment have passed the KEMA and XIHARI type test.


  1. Product feature
  • Fully spring mechanism, high reliability;
  • Excellent breaking ability;
  • The arc extinguish of CB adopts double-interrupter structure, and rated short-circuit breaking current is 63kA;
  • E2-M2-C2 ;
  • Strong current flow capacity;
  • Excellent insulation level, low partial discharge;
  • Excellent corrosion resistance;
  • Advanced designing tool;
  • Double sealing structure;
  • Strict assembly technology;