12kv 24kv Ring Main Unit Rmu Air Insulated Switchgear

++++General 
12/24/36kv-630A Air/Sf6 Gas Insulation Switch-Gear Type Ring Main Unit
FM6 unit type SF6 ring net cabinet with SF6 load switch as main switch, for whole cabinet is suitable for electric distribution automation and compact also expandable metal close switchgear. It characters in its simple structure, flexible operation, reliable interlocking and convenient installation etc., which can provide the satisfactory technical projects both for different application occasions and users. With the adoption of sensor technology and the protection relay up to date, plus the advanced technology and flexible assembly project, FM6 unit type SF6 ring net cabinet can completely meet the requirement of continuously variable market. It can take self-produced FLBS36-36 load switch or SFG type SF6 load switch by ABB; also according to user's demand can be assembled with the internationally top-ranking FGB1 series vacuum circuit breaker with permanent magnetic mechanism made by AREVA or HD4 type SF6 circuit breaker made by AREVA or HD4 type SF6 circuit breaker made by ABB or with our VS1-12 type vacuum circuit breaker with permanent magnetic mechanism. Operational methods for the main switch inside ring main unit can be either manual or electric power driven. And It can meet the requirement of "Four Controls" when matched with FTU and RTU.  
++++Service environment 
a)   Air temperature: Maximum temperature: +40ºC; Minimum temperature:-35ºC 
b)   Humidity: Monthly average humidity 95%; Daily average humidity 90% .
c)   Altitude above sea level: Maximum installation altitude: 2500m
d)   Ambient air not apparently polluted by corrosive and flammable gas, vapor etc.
e)   No frequent violent shake
++++ Main technical specifications

Note: For short circuit breaking and peak current is based on Fuse plus combination.

++++Ring Main Unit Structure
FM6 type switchgear unit is developed and produced by the company itself according to the requirement of domestic electrical system through absorbing the foreign technology, the main components of which are all the imported original binding.
The switchgear has double-fracture, switching on/off and earth switch, reversible contactor,
with SF6 as arc extinguishing medium. Reversible contactor lies in the die casting epikote crust that strengthens the structure.
Every switch is permanently sealed after charged by SF6 gas, the gas leakage can be detected by helium detector.
It is not limited for the vertical or horizontal installation, the typical installation inside the ring main unit is to place a separating steel plate between cable chamber for the horizontal installation, which isolates the bus-bar from cable connector to conform with the most strict
safety requirement for running maintenance.
There are a weak point of structure behind the crust, in case inside happens the arcing when the load switch breaks and makes current, it would be pushed open, then the arc leakage valve on the top of cabinet is pushed open to lead the over-pressure gas flow out of cabinet.
***Upper Unit
SFG LBS with switching on/off and earth switch operating mechanism with mechanical position indicator
crust of busbar cubicle, integrated low-pressure chamber interlocking device, bus bar, control cable tank.
***Lower Unit
Crust, current mutual-inductor, earth switch,
voltage mutual-inductor, cable bottom plate matched with cable strutting pieces