Structural Features
The circuit breaker has an outdoor compact floor-mounted tank-type structure, equipped with a CT35 spring operating mechanism. The mechanism is integrally mounted with the body, ensuring simple installation, easy commissioning, and reliable operation, making it suitable for frequent operations. The mechanism’s lifespan exceeds 10,000 operations.
It adopts a compressed air arc-extinguishing structure with strong breaking capability. It can interrupt 40 kA of fault current up to 12 times, setting a domestic record. The sealing performance is reliable, using imported sealing gaskets. The dynamic seal employs a “V”-shaped sealing ring with a spring pressure compensation structure. The secondary wiring board for the current transformer is supplied by a joint venture, ensuring an annual leakage rate of <0.5%.
The internal current transformers use microcrystalline alloy materials with high magnetic conductivity, and the accuracy class can reach 0.2 or 0.2S. Based on user requirements, up to 12 current transformers can be included. It is capable of handling no-load long lines of up to 50 km without reignition.
Main Technical Parameters of Circuit Breaker
| No. | Parameter Name | Unit | Parameter Value |
| 1 | Rated voltage | kV | 40.5 |
| 2 | Rated insulation level | kV | 185 (lightning impulse, full wave peak) / 95 (power frequency, 1 min) |
| 3 | Rated current | A | 2000 |
| 4 | Mechanical life | Times | 10,000 |
| 5 | Rated SF6 gas pressure (20℃ gauge pressure) | MPa | 0.5 |
| 6 | Alarm/minimum functional pressure (20℃ gauge) | MPa | 0.45 |
| 7 | Rated short-circuit breaking current | kA | 40 |
| 8 | Rated short-circuit making current (peak) | kA | 100 |
| 9 | Rated short-time withstand current (thermal) | kA | 40 |
| 10 | Rated short-time withstand current (dynamic) | kA | 100 |
| 11 | Rated out-of-step breaking current | kA | 10 |
| 12 | Accumulated breaking times (rated short-circuit) | Times | 12 |
| 13 | Rated short-circuit duration | s | 4 |
| 14 | Closing time (rated operating voltage) | s | ≤0.15 |
| 15 | Opening time (rated operating voltage) | s | ≤0.06 |
| 16 | Rated operating sequence | – | O—0.3s—CO—180s—CO* |
| 17 | Rated switching current (single capacitor bank) | A | 400 |
| 18 | SF6 gas annual leakage rate | %/Year | ≤0.5 |
| 19 | SF6 gas moisture content (V/V) | ppm | ≤150×10⁻⁶ |
| 20 | Rated operating voltage (CT14 spring mechanism) | – | See notes |
| 21 | Closing/Opening coil voltage | V | DC 110/220 |
| 22 | Energy storage motor voltage | V | AC 220/380; DC 110/220 |
| 23 | SF6 gas weight | kg | 8 |
| 24 | Circuit breaker weight (including mechanism) | kg | 1400 |
