ZW20-12/630 water test

1. Overview
ZW20A-12/T1000 (630) -25 high-voltage AC vacuum circuit breaker (hereinafter referred to as the circuit breaker) is an outdoor distribution equipment with a rated voltage of 12kV and three-phase AC 50Hz. It adopts vacuum arc extinguishing and SF6 gas as insulation medium, and is an improved product of ZW20-12 column mounted vacuum circuit breaker. The insulation structure technology has been improved, and the sealing performance of the incoming and outgoing line conduits has also been improved. The overall sealing performance is excellent, and the SF6 gas filled inside does not leak and is not affected by the external environment. The spring operating mechanism has been designed for miniaturization and optimized for reliability and stability, using a direct acting chain active and multi-stage trip system. The reliability and stability of the action are several times higher than traditional spring operating mechanisms in China. The contact between the shaft and the sleeve of the main circuit adopts an inward retracting and outward expanding meter chain structure, which has low contact resistance and low temperature rise in the main circuit. So, ZW20A-12 outdoor pole mounted vacuum circuit breaker is a maintenance free product and is a good product among pole mounted circuit breakers.
ZW20A-12 also adds overcurrent protection, mechanism spring energy storage indication, and is equipped with an aviation socket for secondary electrical connection compared to ZW20-12, making it easy to integrate with intelligent controllers.
The excellent electrical and mechanical performance has enabled the ZW20A-12 outdoor column mounted vacuum circuit breaker to be widely used. Mainly used for opening and closing the load current and short-circuit current of 10kV power systems, suitable for protection and control in substations and industrial and mining enterprise distribution systems, and more suitable for frequent operation of the power grid. This product is compatible with the controller and has excellent recloser function, which can meet the requirements of distribution automation systems.
This product mainly complies with the following standards:
GB1984 High Voltage AC Circuit Breaker
GB/T11022 Common Technical Requirements for High Voltage Switchgear and Control Equipment Standards
2. Model and meaning3. Usage conditions

3.1 Altitude: not exceeding 2000m;
3.2 Surrounding air temperature: -40 ° C to+40 ° C, daily temperature difference: daily temperature change not exceeding 25 ° C;
3.3 Wind speed: not exceeding 35m/s;

4. Product features
Flexible and convenient operation: This product can be used for electric energy storage, electric opening and closing, as well as manual energy storage, manual opening and closing functions, and can be operated remotely at close range or far away;
Breaking performance *: breaking short-circuit current of 25KA for 30 times;
Low operating power and high reliability: The newly designed miniaturized electric spring mechanism has reduced the number of components and the rated power of the energy storage motor (about 40W) to * * * level;
Flexible installation method: column mounted lifting or sitting installation can be used;
Maintenance free feature: the main circuit, anime devices and operating mechanism of the circuit breaker are sealed in SF6 gas (zero gauge pressure), which is not affected by the external environment, with stable, reliable and maintenance free performance;
Reliable sealing performance: using mature sealing structure technology, the sealing performance is reliable;
Excellent insulation performance of incoming and outgoing lines: using silicone rubber sleeves to ensure sufficient insulation between terminal blocks, with excellent external insulation performance and safe use;
Four remote functions: can be matched with the controller to achieve remote control, telemetry, remote signaling, and remote adjustment functions.
5. Technical parameters
5.1 Rated parameters of circuit breaker body

5.2 Mechanical characteristic parameters of circuit breaker body

5.3 Main technical parameters of the operating mechanism
5.3.1 Energy storage motor: adopts DC motor, its technical data5.3.2 Manual energy storage operating force: When using the energy storage handle equipped with the mechanism, the operating force is less than 25 kilograms.

5.3.3 Closing Electromagnetic Magnet: Adopting a spiral tube electromagnetic magnet, its coil technical data5.3.4 The coil and technical parameters of the opening electromagnet are the same as those of the closing coil.

Rated working voltage range for closing: 85% -110%; Rated operating voltage range for tripping: 65% -120%, 30% rated voltage should not trip for three consecutive times.
5.4 Configuration of Current Transformers
Current transformer variation: 50/5-1000/5, selected by the user according to their needs; Standard configuration plan: 2 through type current transformers. Additional configuration options: 3 core type current transformers can be configured for 150/5 and below, and 6 core type current transformers can be configured for 200/5 and above, with 3 for protection and 3 for metering.
5.5 Adjustment range of switch protection setting value
Configuring a delay device (also known as a surge controller or timed limit switch overcurrent release), the circuit breaker will have excellent protection performance.
5.5.1 Overcurrent protection Overcurrent value: 5A Overcurrent delay time adjustment range: 40-3000ms
5.5.2 Quick break protection
Quick break current multiple adjustment range: 2-7x Quick break delay adjustment range: 0-120ms
5.5.3 Surge Protection
Surge delay adjustment range: 40-240ms
5.6 Operating current
5.6.1 The power supply needs to be operated when the circuit breaker is in operation. The operating power supply can be externally connected to an AC 220V or DC 24V power supply (the voltage should match the controller power supply), but generally an external operating power transformer or voltage transformer is installed on the 10kV line to obtain an AC 220V operating power supply.
5.6.2 If only single-sided operation of the power supply is required, only one single-phase operation power transformer or a single-phase voltage transformer with a rated voltage of 220V and single winding on the secondary side needs to be installed on the incoming line side.
5.6.3 Although only one side of the power supply needs to be operated, the voltage transformer should also be used for metering purposes. Two secondary double winding voltage transformers should be selected, with a secondary rated voltage of AC 100V and 220V. The primary side is connected to phases A, B, and B, C, with a V-shaped connection. The secondary metering winding (100V) is connected in a V-shape.
5.6.4 It is necessary to operate the power supply on both sides, and install one single-phase operating power transformer or secondary single winding, rated voltage AC 220V single-phase voltage transformer on each side of the switch inlet and outlet lines.
5.6.5 The model of external operating power transformer or voltage transformer is selected by the user, and it is recommended to choose outdoor products with fuses for easy installation. If the external operating power transformer or voltage transformer does not have a fuse, the user must also install an outdoor fuse to protect the external operating power transformer or voltage transformer.
5.6.6 The configuration of the secondary side fuse for operating the power supply is detailed in the accompanying shipping documents.

6. Main components of the product

7. Product Structure

This product consists of three parts: the circuit breaker body, the operating mechanism, and the lifting device.
7.1 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 (as shown in Figure 1). The conductive circuit is connected to the incoming conductive pole, conductive clamp, flexible connection, and vacuum arc extinguishing chamber.
This product uses SF6 gas insulation. The insulation sleeve for the incoming and outgoing lines is 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 structure 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 a double-layer "0" ring. The inlet and outlet conduit are cast as a whole to ensure good air tightness.
7.2 Operating mechanism
The operating mechanism of this product is electric energy storage, electric opening and closing, and also has manual energy storage, manual opening and closing, and overcurrent protection. The entire structure consists of closing springs, energy storage systems, overcurrent release devices, opening and closing coils, manual opening and closing systems, auxiliary switches, and indicators (as shown in Figures 4 and 5)
7.3 Delay Generator
According to user requirements, a delay device (also known as a surge controller or timed limit switch overcurrent release) can be configured to provide better protection performance for circuit breakers. It is possible to adjust the surge delay time to avoid the closing surge, adjust the overcurrent setting and overcurrent action extension time: adjust the quick break current multiple and quick break action delay time.

8. Working principle
8.1 Energy Storage
The energy storage of the mechanism is shown in Figure 3, where Figure 3 (a) shows the final energy storage state of the closing spring, and Figure 3 (b) shows the energy storage state of the closing spring.
8.1.1 Electric energy storage principle: The electric motor applies the output torque to the small gear of the mechanism, which is then transmitted through a chain to the large gear on the main shaft, thereby driving the crank arm to rotate. Store energy in the closing spring. When the screw on the connecting arm presses down the travel switch, the power supply to the motor is cut off, and the energy storage of the spring is completed.
8.1.2 Manual energy storage principle: The output shaft of the manual energy storage transmission mechanism transmits the rotational torque to the small gear through its small gear, fully meshing with the large gear (located on the main shaft and riveted to the large sprocket), thereby driving the crank arm to rotate and storing energy in the closing spring

8.2 Closing
Figure 4 is a schematic diagram of the mechanism closing.
8.2.1 Electric closing
After receiving the closing signal, the moving iron core of the closing electromagnet moves upward, pushing the closing release rod to move upward, causing the closing half shaft to rotate counterclockwise and release the constraint on the closing pawl. At the same time, the closing pawl rotates counterclockwise under the pressure of the roller, releasing the energy storage maintenance. The cam located on the spindle generates an impact force due to the contraction force of the closing spring, which collides with the rocker arm on the manual energy storage shaft (i.e. output shaft), and is transmitted to the switch through the connecting rod to complete the electric closing operation.
8.2.2 Manual Closing
When operating the manual closing device, the toggle plug installed on the closing half shaft rotates counterclockwise, driving the closing half shaft to rotate in the counterclockwise direction, thereby producing the same effect as the closing electromagnet operation and closing.
8.2.3 Reclosing the switch
After releasing the energy of the energy storage spring, the mechanism completes the closing operation. In the closed state, the mechanism stores energy again. After energy storage, the mechanism is in the closed and stored state. In this state, once a trip is triggered and a reclosing signal is received, the mechanism can achieve automatic reclosing once.
8.3 Disconnecting
Figure 5 is a schematic diagram of the opening operation of the mechanism.
8.3.1 Electric circuit breaker
After receiving the opening signal, the moving iron core of the opening electromagnet moves upward, pushing the opening release rod to move upward, causing the opening half shaft to rotate counterclockwise and release the constraint on the opening pawl. At the same time, the opening pawl rotates counterclockwise under the pressure of the roller, and the rocker arm rotates counterclockwise due to the pushing force of the opening spring inside the switch, thus completing the operation.
8.3.2 Manual disconnection
When the manual opening device is operated, the plug installed on the opening half shaft rotates counterclockwise, which drives the opening half shaft to rotate counterclockwise, thereby producing the same effect as the opening electromagnet operation and opening the circuit.
8.3.3 Overcurrent release
When the overcurrent coil in the overcurrent release passes through the specified tripping current, the electromagnet acts and the push rod pushes the tripping rod. Rotate the half axis of the circuit breaker counterclockwise to release the constraint on the latch and produce the same effect as the operation of the opening electromagnet, completing the overcurrent tripping action of the circuit breaker.

8.4 Electrical schematic diagram of control circuit
In the figure, when the mechanism is in the final energy storage state, the normally closed contact of the travel switch WD is connected, and the motor M drives the closing spring to start energy storage. After the energy storage is completed, the normally closed contact of the travel switch WD is disconnected, the power is cut off, and the motor stops running.
After the energy storage of the closing spring is completed, if the mechanism is in the opening position, as long as there is a closing signal, the closing electromagnet HQ will be powered on, and the mechanism will perform electric closing. After the electric closing is completed, the normally closed contact of the auxiliary switch S will be disconnected, and the power supply of the closing electromagnet will be cut off. The WD normally closed contact is connected to the power supply of the energy storage motor M. The motor M drives the closing spring to store energy until the energy storage is completed and the travel switch WD normally closed contact is disconnected.
After the switch is closed, as long as there is a disconnection signal, the normally open contact of the auxiliary switch S has been closed, and the disconnection electromagnetic coil TQ is powered on, and the mechanism performs the disconnection operation. After opening, the normally open contact of auxiliary switch S opens, cutting off the power supply to the opening solenoid coil.9. Operation, acceptance, and storage