66kV 69kV 72.5kV outdoor HV SF6 circuit breaker is a high voltage electric transmission and equipment which is normally used in power grid system. It can open/close the rated current and fault current for realizing protection. It adopts latest design which has great quality for a long service life. 
 
Environment Conditions:
1.Ambient temperature:  -40℃--+ 50℃
2.Wind pressure:≤700 pa
3.Altitude:≤3000m
4.Seismic intensity:≤9degrees
5.Air polluted degree: level Ⅲ
     
| Item | Unit | Technical Data | 
| Rated voltage | kV | 72.5 | 
| Rated frequency | Hz | 50 | 
| Rated current | A | 3150 | 
| Rated short circuit breaking current | Short circuit current | kA | 31.5 | 
| DC component |  | 40% | 
| Duration of rated short time withstand current | s | 4 | 
| Rated short time withstand current | kA | 40 | 
| Rated short circuit making current (peak) | kA | 100 | 
| Rated peak withstand current | kA | 100 | 
| Rated 1 min power frequency withstand voltage (effective value) | To earth | kV | 140 | 
| Breaking isolation | 160 | 
| Rated lighting impulse withstand voltage (peak value) | To earth | 200 | 
| Breaking isolation | 220 | 
| 5 min zero air pressure withstand voltage (effective value) | To earth, Breaking isolation | 75 | 
|
| Rated out of phase breaking current | kA | Ie×25% | 
| Breaking current of fault at close zone | Ie×90%,Ie×75% | 
| Rated line charged breaking current | A | 50 | 
| Rated operation sequence |  | O-0.3s-CO-180s-CO | 
| Constant of first opened pole |  | 1.5 | 
| Closing time | ms | ≤145 | 
| Opening time | ≤60 | 
| Breaking time | ≤60 | 
| Closing-opening time | 60 | 
| Symmetrical time of opening | 3 | 
| Symmetrical time of closing | 5 | 
| Rated pressure of SF6 gas (20℃) | Mpa | 0.5 | 
| SF6 annual leakage rate |  | ≤0.5% | 
| Water content | ppm (v/v) | ≤150 | 
| Potential of wireless radio interference | μV | ≤2500 | 
| Mechanical life | times | 6000 | 
| Mass of each other | kg | 1200 | 
| Mass of SF6 for each breaker | 6 | 
| Resistance of main circuit in each pole | μΩ | ≤80 |