Product name: MV switchgear

Naming rule:

Description:

11kV switchgear is the latest generation of indoor complete power distribution equipment with three phase AC 50Hz or 60Hz, 3.6kV to 12kV single busbar section system. It's mainly used in power plant, substation, industrial and mining factories, as well as high-rise buildings, for power reception and power distribution, with functions of controlling, protecting and detecting electric circuits.

Technical parameters:

 Features:

1. Metal-clad and fully enclosed structure, can prevent dirt and small animals from entrance. 

2. Each small compartment in the switchgear is separated and independent from each other.

3. Fast closing earthing switch is used for earthing and provides short-circuit current closing capacity.

4. All operations can be conducted when the door panel is closed, including breaker switching on and off, breaker trolley's drawing in or out, as well as earthing switch's switching on and off.

5. Reliable latch device is used to effectively prevent misoperation.

6. VCB trolley is maintenance free and the equipped operating mechanism requires only a little maintenance. Good interchangeability of trolleys, very easy to replace circuit breakers.

7. Through the front and rear observation windows in the door panel, breaker's switching status, trolley position, mechanism energy stored status, earthing switch switching position and cable end connection status can be clearly viewed.

8. Secondary wire is laid in ample wire casing, neat and convenient for inspection.

9. Reliable FIVE-PREVENTION interlock can effectively prevent from mal-operation and entrance into energized compartments.

Structure:

1. Switchgear is composed of cubicle and removable parts (so called trolley). The cubicle is separated into several functional compartments by metal sheet, including busbar compartment, circuit breaker compartment, cable compartment and low voltage com

2. Switchgear removable parts can be equipped with VCB trolley, voltage transformer trolley, lightning arrester trolley and fuse trolley.

3. Pressure relief devices are installed above trolley compartment, busbar compartment and cable compartment. Special sealing ring on the door seals the panel door. In case of faults inside the compartments resulting in arc, the pressure is going up inside the switchgear and the pressure relief equipped on the top will open automatically, to release pressure and high temperature gas. In this way, it can ensure the safety of operating staff and the switchgear.

4. The secondary connection of the switchgear and trolleys are conducted via secondary plug coordination. The secondary plug is connected to trolleys through a nylon bellow. The plug is located on the upper right side of switchgear’s trolley compartment. Only when the trolley is on Test position, the secondary plug can be plug in or out. When the trolley is on Operating position, the plug is locked.

5. The switchgear is installed electrical indication device in primary circuit. The device includes high voltage sensors and an indicator, and can indicate high voltage circuit electrical status. It can also cooperate with electromagnetic lock to conduct compulsory latching on operating handle, cubicle door and adjacent cubicles. Thus, it can prevent from withdrawing isolation trolley with loads, prevent earthing switch from energized closing, and prevent from entrance of energized compartment. In this way, it can increase prevention performance of the equipped products.

6. In order to prevent condensation in high humidity or dramatically changed temperature environment, electrical heater is installed separately in circuit breaker compartment and cable compartment, to avoid dielectric accidents in the above conditions.

7. Cable compartment installs additionally earthing copper busbar which goes through adjacent cubicles and with good connection to cubicles. The copper busbar is used for direct earthing components. Since the whole cubicle is joint by aluminum zinc coated steel plates, the cubicle is in good earthing status, thus ensuring safety of operating staff.

Circuit breaker compartment:

1.  Circuit breaker compartment is designed with metal shutter to meet requirements of simultaneously automatic isolation between circuit breaker and busbar side.

2.  A special guide rail is installed inside the circuit breaker compartment for circuit breaker trolley to slide and work on it. The rail has automatic positioning function so that the primary moving stationery contact can be aligned automatically when the circuit breaker pushes in. In the compartment, the trolley has "SERVICE" and "TEST" positions. When the trolley is moving from "TEST" position to "SERVICE" position, the shutter is opened automatically; when trolley is moving in a negative direction, then the shutter is closed automatically to completely isolate primary contact.

Cable compartment:

1. The cable compartment can be fitted with current transformer, earthing switch and surge arrester. The deisng of cable compartment can satisfy various cables in and out modes, for example, bottom in bottom out or top in top out mode.

2.  Supporter adopts epoxy resin insulator with long creepage.

Busbar compartment:

Adjacent busbar compartments adopt metal baffle plate and bushing isolation to prevent possible accident from spreading out. The busbar lapping area is protected by insulation hood.

Low voltage compartment:

Panel and inner space of low voltage compartment can be equipped with relay protective components, meters, air switch, energized display, simulation bus and various secondary components. The modular grid plate is used for mounting indoor secondary equipment. It can flexibly allocate every secondary component and facilitate secondary connection.Fitted with advanced microprocessor-based relay, additional communication interface can be incorporated into substation integrated automation.Microprocessor-based relay provides protective function and possesses multiple functions such as displaying, recording and alarming of substation’s key information.

Interlock devices to prevent misoperations:

Switchgear has a series of interlock devices to fundamentally prevent dangerous situations and misoperations which may result in serious consequences, and thus effectively ensuring safety of operating staff and the switchgear itself. the detailed interlock includes:

1. When circuit breaker and earthing switch are in opening position, the trolley can move from TEST (isolation) position to SERVICE position. If the circuit breaker is in closing condition and is rocked, that is, the trolley tries to move from TEST (isolation) position to SERVICE position and get hampered. Reverse movement has the same result.

2. Only when the trolley is completely engaged in TEST or SERVICE position, the circuit breaker can close.

3. If the trolley is in TEST or SERVICE position without control voltage, the circuit breaker can not close. It can only be manually opened.

4. If the trolley is in SERVICE position, the secondary plug is locked and can not be pulled out.

5. When the earthing switch is closed, the trolley can not move from TEST (isolation) position to SERVICE position, when the trolley is in SERVICE position, the earthing switch can not be closed.

6. Only when the earthing switch is closed, the cable compartment back door can be opened. If the back door is not closed, the earthing switch can not open.

7. After the trolley is removed, the shutter can be locked out with padlock.

Safety of operating staff:

1. Only when cubicle doors are closed or live parts can not be accessed, operation of circuit breakers is allowed.

2. When the cubicle doors are closed, it's possible to check for energizing condition in the cubicle without accessing live parts.

3. Switchgear cubicle and all metal separation plates are earthing with set-up special earthing terminal for connection, providing good earthing continuity.

Installation foundation diagram:

Climate and environment:

1. Altitude: ≤ 1000m

2. Temperature: -15℃ to 40℃

3. Relative humidity: 

Daily average relative humidity: ≤ 95%

Monthly average relative humidity: ≤ 90%

Standards applied:

1.  IEC 62271-200:2003:  Alternating-current metal-enclosed switchgear and controlgear for rated voltage above 1kV and up to and including 52kV

2.  IEC 62271-1:2007:  High-voltage switchgear and controlgear - Part 1: Common specifications

3.  IEC 60060-1:2010:  High-voltage test techniques - Part 1: General definitions and test requirements

4.  GB 3906-2006:  Alternating-current metal-enclosed switchgear and controlgear for rated voltage above 3.6kV and up to and including  40.5kV

5.  GB/T 11022-2011:  Common specifications for high-voltage switchgear and controlgear standards

6.  DL/T 404-2007:  Alternating-current metal-enclosed switchgear and controlgear for rated voltage above 3.6kV and up to and including  40.5kV

7.  GB 50060-2008:  Code for design of high voltage electrical installation (3 ~ 110kV)

8.  GB/T 16927.1-2011:  High-voltage test techniques - Part 1: General definitions and test requirements

Selection of switchgear:

If customer has special requirement, please contact and consult with us.

Typical primary scheme diagram: