Overview 
XGN2-12 (Z) box-type fixed AC metal closed switch equipment (switchgear)is designed according to national standards GB3906 "3-3.5Kv AC metal closed switch equipment", and line with the International Electro technical Commission IEC298 “AC metal closed switch equipment and control facilities ", the DL402, DL404 standards, to achieve" five-prevent” locking requirements. 
Structural features 
XGN2-12 (Z) switchgear is the metal closed box-type structure; skeleton welded from the angle steel. There are circuit breaker rooms, bus room, cable room, relay room in the counter, separated with steel plates between rooms. 
1 circuit breaker room is in the lower part of switchgear, the circuit breaker’s turning is connected with the tension bar and rotating actuator .The upper connection link connect with the upper isolation switch; the lower connection link connect with the current transformers, current transformers connect with lower isolation switch terminals. Circuit breaker room also has pressure 

relief channel, if it occurred the arc, the gas will be released through the channel. 
2 bus room in on the back upper of switchgear. For reducing the switchgear’s height, bus arranged for shape of 品，support with 7350 N bending strength of the porcelain insulator, routing and switching on the isolation terminals connect the two adjacent rooms of the cabinet line between isolation. 
3 cable room is in the lower part of the switchgear, insulator can support a voltage surveillance devices in room, cable fixed in the stunt, the main contact for the end of the programmer, contact the chamber of cable room. Relay room is on the front upper part, an indoor installation of the various boards can be installed, such as relays. Terminals are ranked stunt indoor, the instructions of meters and second signal components can be installed on the doors, and other components, also layout the second small bus on the top. 
4 circuit breaker’s operation system is on the left side of the positive position, its isolation switch at the top for the operation and interlocking institutions. Switchgear is for the two-sided maintenance; repairs relay room two components, maintenance of actuator, mechanical interlocking and transmission parts in front, and repairs circuit breaker, the maintenance the main bus terminals and cables behind. Lights are equipped in circuit breaker room and cable room. The bottom of the front door with a counter-parallel to the direction of the ground copper bus, the section for the 4 × 40mm. 
5 mechanical interlocking: In order to prevent division-load isolation, the misuse of error-breaker, getting into the charged interval by mistake; charged with preventing the earth switch to prevent reclosing with earthing knife, switchgear using the corresponding mechanical interlocking, the principles of mechanical interlocking are as follows:

5.1 blackout operation (running - maintenance) 
Switchgear in the work place, that is, from top to bottom isolation switches, circuit breakers at the closing, and the door before and after had been locked and to live in a run, then the small handle on work position. First gate the circuit breaker, and then pull on the handle to the "breaking closed" position, then circuit breaker can not be switch on, operate the handle into the operation of isolation from the hole pulled down, pulled the gate under isolation location, handle will scored, and then insert the separation operation on the hole, push upward, to push on the isolated location of the gate, and then scored handle operations, switching operation into a grounding hole, push upward, so that the earth switch in a closing position, at this time may pull small handle to "maintenance" position. Open the front door, took out the key on door back to open the back door, power failures are finished, maintenance personnel do maintenance and overhaul to the circuit breaker room and cable room. 
5.2 Transmission operation (Maintenance - Operation) 
If repair completed, need power transmission, its operating procedures are as follows: 
Close the back door, then close the front door when the key taken out. Push small handles from "maintenance" position to pull the "closed-off" position, then the front door is locked, circuit breakers can not be switch on, then insert the handle ground operations by switching operation hole, pull from the up to down ,make earth switches on the gate location. Take handle operations, and then inserted into the operation of isolation on the hole, push upward, make under isolation on a closing position, operating out handle, insert into the operation of isolation under the hole, push from the upward, closing to deal with the isolated location, take out handle, pull the small handle to the work place, at this time could get circuit breaker switch on. 
Rated Current (A): 5-3150 
Rated voltage (kV): 3.6, 7.2,12 
Rated short-circuit commissioner current (kA): 40 50 80 100 
Rated short-circuit breaking current (kA): 16 20 31.5 40 
Protection levels: IP2X 
Dimensions (long*width*depth): 1100 × 1200 × 2650 (general type) 
Quality (Kg): 1000