++++General：
SM66-24 unit type SF6 RMU 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, SM66-12/24 unit type SF6 RMU can completely meet the requirement of continuously variable market. It can take self-produced RLS-12/24 load break switch; also according to the demand of users can be assembled with the internationally top-ranking RCB 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
VSC-12/24 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 enviromenet：
a) Air temperature: Maximum temperature: +40℃; Minimum temperature:-5℃
b) Humidity: Monthly average humidity 95%; Daily average humidity 90% .
c) Altitude above sea level: Maximum installation altitude: 2000m
d) Ambient air not apparently polluted by corrosive and flammable gas, vapor etc.
e) No frequent violent shake
++++Units for all functions：
1. Incoming unit with switch disconnector(Load break switch) schemas
With other extra components optional
2. Outgoing unit with Fuse-switch protection schemas
With other extra components optional
3.Incoming/outgoing circuit breaker protection schemas
With other extra components optional
4. MV metering schemas
With other extra components optional
5. Casings (Bus bar Panel) schemas
With other extra components optional
++++Main technical specifications：
No. | Item | Unit | Parameter |
1 | Rated voltage | kV | 24 |
2 | Rated frequency | Hz | 50/60 |
3 | Rated current | A | 630/800 |
4 | 1min Power frequency withstand voltage | kV | 60 |
5 | Lightning impulse withstand voltage | kV | 125/150 |
6 | Rated short circuit breaking current (peak) | kA | 63 |
7 | Rated active load/close circuit breaking current | A | 50 |
8 | Rated transferring current | A | 1200 |
9 | Rated short circuit making current (peak) | kA | 63 |
10 | Rated cable(line) charging breaking current | A | 50 and 10 |
11 | Cable charge breaking current in earthing fault | A | 20 |
12 | Rated withstand current (peak) | kA | 63 |
13 | Short time withstand current (2s) | kA | 25 |
14 | Mechanism life | times | 2000 |
Note: For short circuit breaking and peak current is based on Fuse plus combination.
