General
XGN2-12 box fixed type metal-enclosed switchgear (switch cabinet for short) is used to receive and distribute electrical energy in 3.6, 7.2, 12KV three phase AC 50Hz system , specially in the frequent operation occasion . Its bus bar system is single bus bar and it can derive single bus bar with branch and double bus bar structure. This switch cabinet conforms to the requirement of national standard GB3906-91 3-35KV AC Metal Seal Switch equipment and the international standard IEC298, and has the function of “ five prevention.”. This switch cabinet’s main switch is composed of ZN28A-12 Yu or the ZN22-12 series vacuum circuit-breaker, the CD17A spring operating mechanism and the CT19B spring operating mechanism, the GN30-12 rotary isolator and the GN22-10 big electric current isolator series product.
Environmental condition
1. Ambient temperature:-25-+40;
2. Altitude is not higher than 1000M;
3. Relative environment humidity:
The daily relative humidity average is not higher than 95%;
The monthly relative humidity average is not than higher 90%;
4. The earthquake's intensity does not exceed 8 degree.
5. Without re, the danger of explosion, chemical corrosion and fierce vibration place and the pollution grade not beyond 3 level.
Structural features
XGN2-12 switch cabinet is the metal-enclosed box structure, its cabinet frame is welded together by the angle iron, the cabinet inside is divided into breaker room, bus bar room, cable room, relays room and so on .Rooms are separated by armor plate.
1. The circuit breaker room is located below in front of the cabinet body. It is connected by the tension bar and the drive mechanism. Line terminal above the breaker connects with isolated switch. Line terminal below the breaker connects with the current mutual inductance which connects isolated switch's line terminal. The circuit breaker room also is equipped with the pressure release channel, if internal electric arc it occurs, the gas passable exhaust channel released the pressure through exhaust channel.
2. Bus bar room is behind, upside cabinet body. .In order to reduce the cabinet body altitude, bus bar room shows itself like the word“Delta” supported by the 7350N anti- curved intensity porcelain insulator . Bus bar connects with upside insulated switches line terminal. Bus bar room in neighboring two cabinets can be isolable.
3. The cable room is behind and below the cabinet body. The supporting insulator inside the cable room may be equipped with the voltage monitor device. The electric cable fixes on the support. When the main line is used to connect, this room is connecting cable room. The relay room is upside and in front of the cabinet body. The installing panel inside the cable room can install each kind of the relay. There are terminal supporters inside. The door of the cable room can be installed indication instrument, the signal part and other twice parts. The top can be installed twice small bus bar.
4. Circuit breaker's drive mechanism is installed face and left side of the breaker. Above it is isolated switch's operation and the interlocking mechanism. The switch cabinet is the two-sided maintenance. The front is twice component checking and repairing relay room and breaker, maintaining the drive mechanism, interlocking mechanism and transmission parts; the back is repairing the main bus bar and cable terminal. There is head lamp inside the breaker .The downside of front door is equipped with bus bar connected by copper paralleling with cabinet. The section is 440mm.
5. Mechanical interlocking: In order to prevent the load from turning on and off the isolated switch and the circuit breaker by mistake, prevent from isolating with charge and earthed switch with charge and turning on the knife switch. The switch cabinet uses the corresponding mechanical interlocking. The mechanical interlocking movement principle as follows:
(1) power-cut operation (operation - examination) The switch cabinet is in the working position, namely the upside and downside isolated switch , the circuit breaker are at turn-on condition, the front and back door has been locked and at electricferous condition, at this time , the small handle was in the working position. First, turn the breaker off, insert the small handle into downside isolated operation hole, then pull to the isolated turn-off position from down to up. Then take the handle down, insert the handle into upside isolated operation hole, pull to the isolated turn-off position from up to down. Then take the handle down and insert it into switch hole, push from down to up to make the switch turn off. At this time, pull the small handle to the examination and repair condition. Then open the front door first, then open the back door,
the power cut operation finish, the examiner maintain and repair the breaker and the cable room.
(2) Power transmission operation (examination repair - movement) If examination repair operation has finished, the power transmission is needed, its operation procedure as follows: Close the back door, after the key is taken out, close the front door, pull the small handle from “the examination repair” position to disjunction and closedown position, at this time the front door is locked, the circuit breaker cannot be turned on. Insert the operation handle to the earthed switch operational hole, push the upside isolator to the turn on position from down to up, take the operation handle out and insert into the downside isolating operational hole, pull the downside isolator to the turn-on operation from down to up and take the operational handle out, pull the small handle to the operation position, at this time, turn the breaker on.6 Product's external dimensions and the structure chart (see chart 1, chart 2, chart 3)