1.1 Main purpose and scope of application
The ZW32-40.5 outdoor AC high-voltage vacuum circuit breaker (hereinafter referred to as the "circuit breaker")is a new generation of outdoor vacuum circuit breakers developed by introducing advanced foreign technology and combining the characteristics of China's power industry.
This circuit breaker is designed for three-phase AC 50/60HZ and has a rated voltage of 40.5KV, making it suitable for outdoor high-voltage switchgear. It is primarily used in the distribution systems of urban and rural power grids, substations, as well as industrial and mining enterprises, for opening and closing load currents, overload currents, and short-circuit currents. Due to the special properties of vacuum circuit breakers, they are particularly suitable for applications requiring frequent operations and oil-free retrofits.
This model of circuit breaker adopts a three-phase separated pole structure, ensuring that a fault in one phase will not cause a three-phase short circuit. The vacuum arc extinguishing chamber is housed within the insulating sleeve of each phase, eliminating the risk of short-circuit faults caused by condensation. The external insulation employs imported outdoor epoxy resin or silicone rubber materials, providing excellent hydrophobic and anti-fouling properties, making it suitable for outdoor environments with high weather resistance requirements and harsh operating conditions. The overall structure of the circuit breaker is compact, with a small footprint,light weight, and easy installation. The interior of the cabinet is filled with transformer oil but contains no sulfur hexafluoride gas, meeting the requirements for oil-free retrofits and environmental protection.
The standards that the circuit breaker meets GB1984: High-voltage Circuit Breaker GB/T11022: Common Technical Requirements for High-voltage Switchgear and Control Equipment JB3855: 3. 6~40. 5kV Outdoor AC High-voltage Vacuum Circuit Breaker DL/T403: 12~40. 5KV AC High-voltage Vacuum Circuit Breaker Ordering Technical Conditions IEC56: AC high-voltage Circuit Breaker
a. Environmental temperature: maximum temperature - 40℃, minimum temperature - 45℃, maximum daily temperature difference - 25℃;
b. Environmental humidity: Daily average relative humidity≤95%, monthly average relative humidity≤90%,daily average saturated vapor pressure≤2. 2×10-3MPa, monthly average saturated vapor pressure ≤1. 8×10-3MPa;
c. Altitude: not exceeding 2000m;
d. The seismic intensity shall not exceed level 8;
e. Wind speed: not exceeding 35m/s;
f. Pollution level: IV;
g. Places without fire, explosion, chemical corrosion, and frequent severe vibration.
When the usage conditions exceed the above range, the allowable range and technical measures should be determined through consultation with the supplier.
Table 1 : Main Rated Parameters
| No . | Name | Unit | Parameters | |||||||||||
| 1 | Rated voltage | KV | 35 | |||||||||||
| 2 | Rated frequency | HZ | 50/60 | |||||||||||
| 3 | Rated insulation level | 1-minute rated power frequency withstand voltage | KV | Wet: 80 Dry: 95 (phase to phase ,relative to the ground)/95 (fracture surface) | ||||||||||
Rated lightning impulse withstand voltage (peak value) | Alternating and facing the ground | 185 | ||||||||||||
| Fracture Surface | 185 | |||||||||||||
| 4 | Rated current | A | 630-2500 | |||||||||||
| 5 | Rated short circuit breaking current | KA | 25 、31.5 | |||||||||||
| 6 | Rated short-circuit closing current (peak) | 63 、80 | ||||||||||||
| 7 | Rated dynamic stability current (peak value) | 63 、80 | ||||||||||||
| 8 | Rated thermal stability current (effective value) | 25 、31.5 | ||||||||||||
| 9 | Rated short-circuit breaking current times | Times | 30 | |||||||||||
| 10 | Rated thermal stability time | S | 4 | |||||||||||
| 11 | Rated operating sequence | CO-0 .3S-CO-180s-CO | ||||||||||||
| 12 | Mechanical life | Times | 10000 | |||||||||||
| 13 | Allowable wear thickness of contacts | mm | 3 | |||||||||||
| 14 | Secondary circuit 1-minute power frequency withstand voltage | KV | 2 | |||||||||||
| 15 | Weight | kg | 580/780 | |||||||||||
Table 2: Main Rated Parameters
| No . | Name | Unit | Parameters | |||||||||||
| 1 | Clearance between open contacts | mm | 18±1 | |||||||||||
| 2 | Contact over-travel | 4±1 | ||||||||||||
| 3 | Interphase center distance | 700±1 .5 | ||||||||||||
| 4 | Bouncing time of closing contact | ms | ≤5 | |||||||||||
| 5 | Three-phase on-off asynchrony | ≤2 | ||||||||||||
| 6 | Opening time | ≤50 | ||||||||||||
| 7 | Closing time (electric closing) | ≤100 | ||||||||||||
| 8 | Average opening speed | m/s | 1.4~1.8 | |||||||||||
| 9 | Average closing speed | 0.9~1.1 | ||||||||||||
| 10 | Resistance of each phase conductive circuit | μΩ | ≤50 | |||||||||||
