Pure air insulated Ring Main Unit (RMU) switchgear for Grid Upgrade-12kV 24kV
Key attributes
| Brand | ROCKWILL |
| Series | SM66 |
| Rated voltage | 24kV |
| Rated frequency | 50/60Hz |
| Rated current | 800A |
| Lightning impulse withstand voltage | 125/150kV |
| Short time withstand current (2s) | 25kA |
Description
Pioneer in China's eco-friendly switchgear sector, we have specialized in R&D and manufacturing of SF₆-free switchgear for decades. With core technologies, we have established industry standards. Boasting a fully independent end-to-end production chain, we have built a product matrix of zero-emission and high-reliability eco-friendly switchgear, making us a trusted choice for power grid construction.
SM66-12/24 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 user's demand 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.
Technical feature:
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Good Insulation Performance；
-
Strong Arc Extinguishing Ability；
-
High Safety；
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Flexible and Reliable Operation；
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Compact Structure and Modular Design；
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High Degree of Intelligence.
Technology parameters:
|
No |
Item |
Unit |
Parameter |
|
|
1 |
Rated voltage |
kV |
12 |
24 |
|
2 |
Rated frequency |
Hz |
50/60 |
|
|
3 |
Rated current |
A |
630 |
800 |
|
4 |
1min Power frequency withstand voltage |
kV |
48 |
60 |
|
5 |
Lightning impulse withstand voltage |
kV |
75 |
125/150 |
|
6 |
Rated short circuit breaking current (peak) |
kA |
80 |
63 |
|
7 |
Rated active load/close circuit breaking current |
A |
63 |
50 |
|
8 |
Rated transferring current |
A |
1700 |
1200 |
|
9 |
Rated short circuit making current (peak) |
kA |
80 |
63 |
|
10 |
Rated cable(line) charging breaking current |
A |
50 and 10 |
|
|
11 |
Cable charge breaking current in earthing fault |
A |
20 |
20 |
|
12 |
Rated withstand current (peak) |
kA |
80 |
63 |
|
13 |
Short time withstand current (2s) |
kA |
31.5 |
25 |
|
14 |
Mechanism life |
times |
2000 |
|
Note: For short circuit breaking and peak current is based on Fuse plus combination.
Normal Service Conditions
| Temperature upper limit | +40 °C |
| Temperature 24h avg | +35 °C |
| Temperature lower limit | –25 °C |
| Altitude | ≤ 1 000 m |
| Relative humidity (24h) | ≤ 95% (at +40 °C) |
| Relative humidity (monthly) | ≤ 90% |
| Water vapour pressure (24h) | ≤ 2.2 kPa |
| Water vapour pressure (monthly) | ≤ 1.8 kPa |
| Solar radiation | ≤ 1 000 W/m² |
| Wind speed | ≤ 34 m/s |
| Pollution degree (indoor) | Class II |
Typical Application Scenarios
- Urban Distribution Network Ring Main Supply
- Residential Substation Distribution
- Industrial Park Distribution
- Commercial Complex Distribution
- Railway/Transit Power Supply
- Wind/Solar PV Collection Lines
- Legacy Distribution Network Retrofit
Documentation Resource Library Ring Main Unit
FAQ for Ring Main Unit
SM66-12/24 is designed for the "continuously variable market," featuring advanced sensor technology and protection relays. Produced within our specialized SF₆-free manufacturing ecosystem, it can achieve "Four Controls" when matched with FTU and RTU, making it an ideal, high-reliability choice for smart grid automation.
Q:How does your SF₆-free R&D expertise improve the flexibility of the SM66-12/24 RMU?
A:Our extensive experience in SF₆-free and eco-friendly R&D allows us to provide a flexible assembly project. This expertise ensures the SM66-12/24 can be equipped with various components—such as our self-produced RLS load break switches or top-ranking vacuum circuit breakers—while maintaining the simple structure and reliable interlocking that characterize our zero-emission product line.
