Description

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

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

Technical data

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