KYN28A-12 armored removable AC metal enclosed switchgear

Overview

This device is an indoor metal armored withdrawable switchgear (hereinafter referred to as switchgear),and it is a complete power distribution device for 3.6-12 kV three-phase AC 50Hz single busbar and single busbar segmental system.It is mainly used in power plants,small and medium-sized generators for power transmission,and power distribution for industrial and mining enterprises,and power reception and transmission of secondary substations in electrical systems,as well as starting of large high-voltage motors,etc.It is used for control,protection and monitoring.

This switchgear meets the requirements of IEC298,GB3906 and other standards.It has the interlock function of preventing the handcart of the circuit breaker from being drew in and out under load,preventing the circuit breaker from being opened and closed by mistake,preventing the circuit breaker from being closed when the grounding switch is in the closed position when it is charged,preventing mistaken entry into the electrified room,and preventing the grounding switch from being closed by mistake when it is charged.It can be equipped with VSl vacuum circuit breaker and ABB’s VD4 vacuum circuit breaker.It is a power distribution device with superior performance.

Environmental  conditions

a Ambient air temperature:upper limit +40°℃,lower limit -10°℃;
b   Altitude:≤1000m;
C Relative humidity:the daily average relative humidity is not more than 95%,and the monthly average relative humidity is not more than 90%;
d Earthquake:the magnitude does not exceed 8;
e The surrounding air should not be polluted by corrosive or combustible gases,water vapor,etc;
f There is no serious pollution and frequent severe vibration,and the severity design meets the requirements of category 1 under severe conditions.

Structure introduction

The switchgear is designed according to the armored metal-enclosed switchgear in GB3906-91.The rectifier body is composed of two parts:the cabinet body and the central withdrawable part (handcart),as shown in Figure 1.The cabinet is divided into four separate compartments,and the protection level of the outer shell is IP4X and it is IP2X when the door of each small room and the door of the circuit breaker is opened.With overhead incoming and outgoing lines,cable incoming and outgoing lines and other functional schemes,it can be a power distribution device in various schemes after arrangement and combination.The switchgear can be installed,debugged and maintained from the front,so it can be double-arranged back to back and installed against the wall,which improves the safety and flexibility of the switchgear and reduces the floor space.

Switchgear structure diagram

Switchgear  Boundary  Dimensions

A.Handcart
The frame of the handcart is made of thin steel plates processed by CNC machine tools and then riveted and welded. According to the application,handcarts can be divided into circuit breaker handcarts,voltage transformer handcarts, isolation handcarts,metering handcarts,etc.Handcarts of the same specification can be replaced.The handcart has an isolation position,a test position and a working position in the cabinet,and each position is equipped with a positioning device to ensure that the handcart cannot be moved casually when it is in the positions mentioned above,and the interlock must be released when the handcart is moved.

B.Busbar chamber
The busbar is led from one switchgear to another,and fixed by the branch busbar and the static contact box.The flat branch busbar is connected to the static contact box and the main busbar by bolts,without any other clamp or insulator
connection.When the user and project have special needs,the connecting bolts on the busbar can be encapsulated with insulation and end caps.When the busbar passes through the partition of the switch cabinet,fix it with the busbar bushing. If an internal fault arc occurs,it can limit the accident from spreading to adjacent cabinets and ensure the mechanical strength of the busbar.

C.Cable chamber
Current transformers,grounding switches,lightning arresters and cables can be installed in the chamber,and a detachable aluminum plate with slots can be prepared at the bottom to ensure convenient construction on site.

D.Relay instrument chamber
The relay instrument chamber is used to install various components such as relays,instruments,signal indicators,and operationswitches.In addition,a small busbar room can be added on the top of the instrument room according to users’ requirements,and sixteen control small busbars can be laid.

E.Pressure relief device
There is a pressure relief device above the handcart room,busbarroom,and cable room.When an internal fault arc occurs in the circuit breaker,main busbar,and cable room,the internal air pressure of the switchgear rises with the occurrence of the arc.After reaching a certain pressure,the pressure of the top device is released,the metal plate will be opened automatically to release the pressure and discharge the gas to ensure the safety of the operator and the switchgear.

Lock device
The connection between the middle door and the cabinet body adopts a lock structure,and is equipped with a lifting mechanism,which makes the opening of the middle door more convenient.When the middle door is closed,the connection strength between it and the cabinet body is better,which enhances the ability to effectively combat internal arcing faults.