1. Product overview

KYN28A-12 metal armored withdrawn mid-mounted switchgear is a new development of VE vacuum switchgear technology widely absorbed by our factory and the advantages of similar products at home and abroad

type of mid-mounted switchgear. It is currently the most advanced switchgear in China.

Compliance with standards:

GB3906-91《3~35kV AC metal-enclosed switchgear》

GB11022-89 "General Technical Conditions for High Voltage Switchgear"

IEC298 (1009) "AC metal closed switchgear and control equipment with rated voltage above 1kV and 50kV and below"

DL404-91 "Technical Conditions for Ordering Indoor AC High Voltage Switch Cabinet"

2. Product use

KYN28A-12 metal armored withdrawable mid-mounted switchgear is used for 6~10 kV power distribution device as a single busbar system to receive and distribute electric energy.

3. Environmental conditions of product use

(1) Ambient temperature: maximum temperature +40 °C, minimum temperature -10 °C

(2) Ambient humidity: daily average relative humidity ≤95%, monthly average relative humidity ≤ 90%

(3) Altitude: below 1000m

(4) Seismic resistance: the earthquake intensity does not exceed 8 degrees

(5) The surrounding air should be free from obvious pollution such as corrosive combustible gas and water vapor

(6) There is no regular violent vibration place. The harsh design meets Class I requirements under harsh conditions.

(7) When used under normal environmental conditions exceeding the provisions of GB3906, the user and our company shall negotiate.

Widely used in power plants, substations, industrial and mining enterprises, high-rise buildings, etc.

This switchgear can be installed, debugged and maintained from the front, so it can be installed against the back to form a double column and against the wall, which improves the safety and flexibility of the switchgear and reduces the floor space; The cabinet adopts advanced stacked structure of building blocks, making it firm, compact and beautiful; High reliability of the combination unit type, each combination unit isolated from each other into an independent chamber, the bus bar is wrapped by a heat shrinkable tube with good insulation and easy heat dissipation; Interlocking device to prevent misoperation; The trolley is highly interchangeable and the combination scheme is persified; Small size, light weight, easy to operate, safe and reliable.

1. Shell and partition

The shell and partition of the switchgear are processed by CNC machine tools by aluminum-zinc steel plate, and adopt multiple folding process, so that the whole cabinet not only has high precision, strong corrosion resistance and oxidation resistance, but also because of the use of multiple folding process to make the cabinet body lighter weight and high mechanical strength than other similar equipment. The cabinet adopts an assembled structure, which is connected by riveting nuts and high-strength bolts, which makes the processing and production cycle short, the parts are versatile, the floor space is small, and it is convenient to organize production. The switchgear is pided into a handset room, a busbar room, a cable room, a relay instrument room (low voltage room), and each compartment shell is independently grounded. The door of the switchgear adopts a spray process, which makes its surface impact and corrosion resistant and ensures the beauty of the appearance.

2. Handcart

The skeleton of the hand car is made of steel plate after CNC machine machining and riveting. The handcart and the cabinet are insulated and coordinated, and the mechanical interlock is safe, reliable and flexible. According to the use, handcars can be pided into circuit breaker handcarts, voltage transformer handcarts, metering handcarts and so on. The height and depth of all types of handcarts are uniform, and handcarts of the same specification can be interchanged. The handcart has an isolation test position and a working position in the cabinet, and each position is equipped with a positioning device to ensure the reliability of the interlock, and must be operated in accordance with the interlock anti-misoperation procedure. All kinds of hand carts are used nuts, screw rocking to propell, exit, its operation is light and flexible, suitable for the operation of duty personnel. When the handcart needs to be removed from the cabinet, a special transfer cart can be easily withdrawn for various inspections and maintenance; Moreover, it adopts the mid-mounted type, and the whole handcart is small in size, and it is extremely convenient to inspect and maintain.

3. Compartment inside the switchgear

The main electrical components of switchgear have their own independent compartments, namely: circuit breaker car room, busbar room, cable room, relay instrument room. Each compartment has IP2X protection level; In addition to the relay room, the other three compartments have their own pressure relief channels. Due to the mid-mounted form, the cable room position is greatly increased, so that the device can be connected to multiple cables.

4. Prevent misoperation of the interlock device

The switchgear has a reliable interlock device to provide reliable safety protection for operators and maintenance personnel, and its functions are as follows:

(1) After the handcart is moved from the working position to the isolation/test position, the movable curtain plate separates the static contact box to prevent mistakenly entering the live compartment. For access, the movable curtain can be locked with a padlock.

(2) When the circuit breaker is in the closed state, the handcart cannot be pulled out from the working position or pushed from the isolation/test position to the working position; The circuit breaker's handcart is sufficiently locked to the test position or working position before it can be operated.

(3) The grounding switch can only be operated when the handcart is in the isolation/test position and outside the cabinet, when the grounding switch is in the closed state, the handcart cannot be retreated from the isolation/test position to the working position.

(4) When the handcart is in the working position, the secondary plug is locked and cannot be unplugged.

5. Pressure relief device

There are pressure relief devices above the handcar room, busbar room and cable room, when the circuit breaker or bus bar has an internal fault arc, with the appearance of arc, the internal air pressure of the switchgear rises, and the pressure release metal plate assembled on the top will be automatically opened to release pressure and exhaust gas to ensure the safety of operators and switchgear.

6. The secondary plug is interlocked with the position of the handcart

The contact between the secondary wire on the switchgear and the secondary wire of the handcart is realized by means of a secondary plug. The moving contact of the secondary plug is connected to the handcart by a nylon bellows, and the secondary static contact seat is mounted on the upper right side of the switchgear circuit breaker compartment. The secondary plug can only be inserted and unplugged when the handcart is in the test/isolation position, and the secondary plug is locked and cannot be released when the handcart is in the working position due to the mechanical interlock effect. The circuit breaker handcart can only be opened before the secondary plug is not connected, and because the closing mechanism of the circuit breaker handcart is locked by electromagnetism, it cannot be closed.

7. Live display device

The switchgear is equipped with a live display device. The device consists of two parts: a high-voltage sensor and a portable display. The sensor is installed on the bus or feeder side, the plug interface of the display is installed on the low-voltage compartment of the switchgear, when it is necessary to detect whether the ABC three-phase is live, the plug of the portable display can be inserted into the L1L2L3 interface, if the display is active, it means that the bus or feeder side is charged, otherwise, it means that it is not charged. At the same time, it can also be used as a phase sequence detector or electro-optical indicator, and its function is also to detect whether it is charged on the high voltage side.

8. Prevent condensation and corrosion

In order to prevent the danger of condensation in climatic environments with high humidity or large temperature changes. Heaters are installed separately in the circuit breaker and cable chambers for use in these environments and to prevent corrosion.

9. Grounding device

A 5×40mm grounded copper bar is set up separately in the cable room to run through the adjacent switchgear and have good contact with the cabinet. This ground bar is used by components that are directly grounded. At the same time, because the entire cabinet is spliced with aluminum-zinc plate, the entire cabinet is in a good grounding state to ensure the safety of the operating personnel and the cabinet.