summary:

VSC-12 indoor high-voltage vacuum circuit breaker (hereinafter referred to as circuit breaker) is applicable to indoor switchgear of 12kV power system. As a protection and control unit for power grid equipment and power design of industrial and mining enterprises, it is applicable to switching various loads of different nature and occasions of frequent operation and multiple breaking of short circuit current. The product adopts a new circuit breaker operating mechanism, and the NGVSC primary part can use brand fixed sealing pole, which can seal the vacuum arc extinguishing chamber and the main electrical circuit parts into a whole, protect the arc extinguishing chamber from the impact of collision, dust and condensation, and has strong environmental adaptability, which greatly reduces the operation and maintenance costs, and truly realizes that the primary part of the product is maintenance-free, and the operating mechanism is less maintenance; Operating mechanism and circuit breaker body - body design, verified by type test; It has E2 electrical life and M12 mechanical life.

Structure and working principle:

■ Main structure

The overall structure of VSC indoor high-voltage vacuum circuit breaker adopts the operating mechanism and the primary part is arranged in front and back, and the primary part is three-phase floor-type structure. The upper and lower outlet bases and arc extinguishing chambers are solidly sealed with epoxy resin APG process, so that there is no dust accumulation on the surface of the arc extinguishing chamber, which can prevent the vacuum arc extinguishing chamber from being damaged by external factors, and ensure that it can be used in the humid, hot and polluted environment.

When the circuit breaker is in the closing position, the main circuit current path is: (see Figure 2)

The upper outlet base 21 is connected to the static contact in the vacuum arc extinguishing chamber, and then to the lower outlet base 20 through the moving contact, the moving conductive rod and the soft connection connected with it.

■ Operating mechanism (see Fig. 1 and Fig. 2)

The operating mechanism is a modular spring energy storage operating mechanism. The operating mechanism is integrated with a closing unit, an opening unit composed of one or several overcurrent release electromagnets, auxiliary switches, indicating devices and other components; The front is equipped with closing and opening buttons, manual energy storage handle, spring energy storage status indicator, closing and opening indicator, etc.

■ Energy storage

The energy required for closing the circuit breaker is provided by the energy storage of the closing spring. The energy storage can be completed either by the external power drive motor or manually by using the energy storage handle.

Energy storage operation: It is carried out by the energy storage motor 2 fixed on the side plate of the mechanism, or by pulling the energy storage handle 8. The motor drives the gear transmission system (3, 4, 5) when storing energy electrically, and the gear shaft 9 drives the gear 5 when storing energy manually. When the gear 5 rotates, the energy storage shaft 6 is driven by the overrunning clutch 10 to stretch the closing spring for energy storage. When the energy storage position is reached, the energy storage holding switch 14 on the mechanism holds the roller on the cam, and the overrunning clutch is disengaged. At the same time, the connecting plate 7 drives the energy storage indicator to turn over and display the "stored energy" mark and switch the auxiliary switch to cut off the power supply of the energy storage motor. At this time, the circuit breaker is in the closing preparation state.

■ Closing

During closing operation, Whether the "closing" button is pressed by hand or the closing electromagnet is actuated by remote operation, the energy storage can keep the pawl 14 rotating and make the pawl release the roller on the cam 11. The closing spring retracts and drives the cam 11 to rotate through the energy storage shaft 6 and the overrunning clutch. The cam drives the linkage mechanism (15, 16, 17) Drive the insulating pull rod 19 and the moving contact into the closing position, and compress the contact disc spring to maintain the required contact pressure of the contact. After the closing action is completed, the closing holding switch 13 and the roller on the holding mechanism 12 remain in the closing position. At the same time, the energy storage indicator and auxiliary energy storage switch are reset, and the motor power supply circuit is connected. If the external power supply is also connected, it will enter the energy storage state again. The connecting rod 1 will pull the on/off indicator to display the "on" sign, and the transmission connecting rod will pull the main auxiliary switch to switch.

■ Opening

The "opening" button can be pressed, and the external power supply can also be reliably connected to make the opening release electromagnet or the overcurrent release electromagnet act to unlock the closing holding pawl 13 and the roller on the holding mechanism 12 to realize the opening operation. The energy stored by the contact spring and the opening spring 18 separates the dynamic and static contacts of the arc extinguishing chamber in the solid-sealed pole. At the later stage of the opening process, the hydraulic buffer absorbs the residual energy during the opening process and limits the separation position.

The connecting rod 1 pulls the closing/opening indicator to display the "opening" mark. At the same time, the counter is pulled to realize the counter counting. The transmission connecting rod pulls the main auxiliary switch to switch.

Note: When the circuit breaker is in the closing state or the locking device is selected without unlocking the locking device and the handcart circuit breaker is in the process of pushing and pushing, the closing operation cannot be carried out.

■ Anti-mirror interlocking

The circuit breaker can provide perfect anti-misoperation function. (See Figures 3 and 4)

1. After the closing operation of the circuit breaker is completed, close the interlocking bending plate

1. Move up to make the closing interlock plastic part 2 snap the closing plastic part 3 on the closing holding shaft, and it will not be able to close again when the circuit breaker is not opened.

2.After the closing of the circuit breaker, if the closing electrical signal is not removed in time, the anti-tripping control circuit inside the circuit breaker will cut off the closing circuit to prevent multiple reclosures.

3. If electrical closing locking is selected, closing operation is prevented without unlocking the locking device.

Note: The power of the closing locking device is 3.2W, and the working voltage range is 0.65~1.1 times of the rated voltage