ZW20-12 Outdoor High Voltage Vacuum Circuit Breaker

Overview of ZW20 Vacuum Circuit Breaker:
ZW20-12 outdoor AC high-voltage boundary vacuum circuit breaker is a user boundary switch
It mainly consists of three parts: ZW20-12 vacuum circuit breaker body, fault detection controller, and external voltage transformer
The three are electrically connected through aviation sockets and outdoor sealed control cables, with fault detection, protection control, and communication functions
Can reliably judge and detect milliampere level zero sequence current and phase to phase short-circuit fault current inside and outside the boundary, achieving automatic removal of single-phase grounding faults and phase to phase short-circuit faults
The main switch adopts vacuum arc extinguishing and SF6 gas insulation. The box body refers to the gas sealing, explosion-proof, and insulation structure technology of Toshiba Corporation in Japan
The overall sealing performance is excellent, and the SF6 gas filled inside does not leak or be affected by the external environment,
The spring operating mechanism has been miniaturized and optimized for performance, significantly improving the reliability of the action compared to traditional spring mechanisms in China. The contact between the shaft and the sleeve of the main circuit adopts an inward and outward tension chain structure, resulting in low contact resistance and low temperature rise in the main circuit.
Reliable product performance is a true maintenance free product.
Environmental conditions for the use of ZW20 vacuum circuit breaker:
1. Surrounding air temperature: -40 ℃~+40 ℃; Daily temperature difference: The daily temperature change does not exceed 25 ℃; According to the properties of SF6 gas, when the ambient temperature is -40 ℃ and the internal pressure of the box is 0.05Mpa, SF6 is still in the gaseous state to ensure the normal operation of the product. When the ambient temperature is -40 ℃ and the gauge pressure is 0.05Mpa, the liquefaction point of SF6 is -55 ℃; Zero gauge pressure, SF6 liquefaction point will not exceed -60 ℃.
2. Wind speed not exceeding 35m/s;
3. Places without flammability, baozha hazards, strong chemical corrosives such as various acids, alkalis, or thick smoke, and places with severe vibrations.
4. Altitude: ≤ 1000m;
5. Coverage thickness: 10mm;
6. Air pollution level: Level IV;
7. Seismic intensity: ≤ 7 degrees;
8. Neutral grounding method for power grid: neutral point not grounded, neutral point grounded through arc suppression coil, neutral point grounded through low resistance.

Main technical parameters of ZW20 vacuum circuit breaker:
3.1 The rated parameters of the circuit breaker are shown in Table 1
serial number
project
unit
Numerical value
1
rated voltage
KV
12
2
rated frequency
Hz
50
3
rated current
A
630
4
Rated short-circuit breaking current
KA
20
5
Rated peak withstand current (peak)
KA
50
6
Rated short-time withstand current (4S)
KA
20
7
Rated short-circuit closing current (peak)
KA
50
8
Mechanical lifespan times
time
10000
9
Rated short-time breaking current breaking times
time
30
10
Power frequency withstand voltage (1min): dry test (phase to phase, ground/fracture)
KV
42/48
11
Lightning impulse withstand voltage (peak) phase to phase, relative/fracture
KV
75/85
12
Rated operating sequence
KV
Min-0.3s HeFen-180s HeFen
13
Rated operating voltage auxiliary circuit rated voltage
V
AC220
Note: When the altitude of the product usage site exceeds 1000m, the insulation withstand voltage should be adjusted according to GB/T11022-1999.
3.2 Circuit breaker assembly adjustment parameters are shown in Table 2
serial number
project
unit
Numerical value
1
Contact opening distance
mm
9+1-0.5
2
Contact overtravel
mm
3+1-0.5
3
Average opening speed
m/s
1.2±0.2
4
Average closing speed
m/s
0.6±0.2
5
Contact closing bounce time
ms
≤2
6
Center distance between poles inside the box
mm
135
7
Center distance between poles outside the box
mm
280
8
Synchronization time difference of three-phase disconnection
ms
≤2
9
DC resistance of each pole circuit
μ Omega
≤200
10
Closing time
ms
≤45
11
Opening time
ms
≤45
12
Allowable wear thickness of moving contact
mm
3
13
Contact pressure during closing
N
2000±200
14
Rated pressure of SF6 gas (gauge pressure)
MPa
0
15
Net weight
Kg
185
3.3 Main technical parameters of the operating mechanism
3.3.1 Energy storage motor: DC series excited motor is used, and its technical data is shown in Table 3
Model YJ220-5301BS rated voltage (DC 220V) normal operating range (85~120 rated operating voltage)
Energy storage time under rated power (20W) and rated voltage (≤ 5s)

3.3.2 Manual energy storage operation force: When using the energy storage handle equipped with the mechanism, the maximum operation force is less than 25 kilograms.
3.3.3 Closing Electromagnetic Magnet: A spiral tube electromagnetic magnet is used, and its coil technical data is shown in Table 4.
Rated voltage DC 220V Rated current 3.9A Rated power 860W 㺔 ℃ Coil resistance 56 Ω
Normal operating voltage range 65~110 rated operating voltage

3.3.4 Technical parameters of the opening electromagnetic coil, the same as the closing coil.
3.4 One current transformer is installed in each phase A and C of the circuit breaker body, with a transformation ratio of 400/5, for phase to phase protection.
3.5 Zero sequence current transformer
One zero sequence current transformer with a transformation ratio of 20/1 is installed in the circuit breaker body. It has a good linear relationship in the zero sequence current range of 0.1-5A, and the transformation ratio error under rated load (0.1VA) is less than 3. When the zero sequence current is 400A, the secondary output current is not less than 5A.
3.6. Operating power supply
3.6.1 The power supply needs to be operated when the circuit breaker is in operation. The operating current can be supplied by an external AC or DC 220V power supply, but generally an external operating power transformer or voltage transformer is installed on a 10KV line to obtain an AC 220V operating power supply with a capacity of 1kva and a weight of 45kg.
3.7 Technical parameters of the controller are shown in Table 5
serial number
project
unit
parameter
1
Input working voltage
V
AC220
2
Input working voltage frequency
HZ
50
3
Allowable fluctuation range of input working voltage

±20
4
Total power consumption
W
＜10
5
Sampling phase current input value once
A
Adjustable from 0 to 3600
6
Sampling zero sequence current input value once
0~20
7
Sampling error of power input value

±5
8
Overcurrent protection primary current setting range (secondary)
A
Adjustable from 0 to 1500
9
Quick break protection primary current setting range (secondary)
Adjustable from 0 to 3600
10
Delay time value of overcurrent protection action
ms
Adjustable from 0 to 5000
11
Zero sequence protection primary current setting range
A
0~20 adjustable
12
Zero sequence protection action delay time value
S
Adjustable from 0 to 1200
13
Number of reclosing cycles
time
0~1
14
First coincidence time
S
0~9.9
15
Simple remote control distance
rice
100
16
Net weight of controller
kg
12

The basic structure of ZW20 vacuum circuit breaker body:
4.1 Structure of Circuit Breaker Body
The structure of the circuit breaker body consists of a conductive circuit, an insulation system, sealing components, and a housing. The conductive circuit is composed of incoming and outgoing conductive poles, conductive clamps, flexible connections, and vacuum arc extinguishing chambers. This product uses SF6 gas insulation. The incoming and outgoing insulation sleeves are made of epoxy resin and silicone rubber cast as a whole. To reduce the volume of the switch, corner sleeves are used for phases A and C to ensure good external insulation; The internal adopts a composite insulation structure, which can achieve the corresponding insulation level without filling SF6 gas. This product adopts a mature sealing structure. The mechanism cover and shell cover are sealed with stamped grooves, and the output pointer shaft is sealed with double-layer "O" rings. The inlet and outlet conduit are cast as a whole to ensure good air tightness.
4.2 Operating Mechanism: The operating mechanism of this product is composed of electric energy storage, electric opening and closing, as well as manual energy storage, manual opening and closing. The entire structure is composed of closing springs, energy storage systems, opening and closing coils, manual opening and closing systems, auxiliary switches, and energy storage indicators

Ordering Notice:
When placing an order, the user should provide the model, name, quantity, current ratio, specifications, quantity, and accuracy level of the current transformer for the breaking current of the product, as well as whether a transition frame is installed and the height dimension of the transition frame. When ordering for the renovation of old stations, users should specify the original installation dimensions of the old station.
After-sales service
Our company adheres to the spirit of quality, efficiency, and development, with the concept of high-quality products and thoughtful services. We solemnly promise to you publicly and responsibly as follows:
1. The minimum warranty period for all products sold by our factory is one year, and some products have a three-year warranty. During the warranty period, free on-site repairs are provided, except for malfunctions or damages caused by human factors or uncontrollable natural phenomena.
2. Upon receiving the repair notice, arrive at the scene within seven working days and resolve the issue.
3. Users can consult technical issues through after-sales telephone and obtain clear solutions.
When users experience performance failures during normal use, our company promises the above warranty services. In addition, if there are clear provisions in the applicable laws and regulations of the country, our company will comply with the relevant laws and regulations.
During the warranty period, paid repair services will be provided for the following situations:
Damage caused by human or uncontrollable natural phenomena.
Malfunctions or damages caused by improper operation.
Malfunctions or damages that occur due to modifications, disassembly, or assembly of the product