As a set of power transmission and distribution electrical equipment, the Ring Main Unit (RMU) plays a crucial and significant role in the power system. It is mainly applied in the distribution substations of load centers such as urban residential communities, high-rise buildings, large public buildings, factories and enterprises, as well as in box-type substations. In these scenarios, the RMU controls and protects circuits. For instance, in urban residential areas, it distributes power from superior substations to buildings, ensuring stable supply during normal operation and quickly cutting off circuits in case of overloads or short circuits to safeguard equipment and prevent fault spread. In factories, it precisely manages power supply according to equipment needs and responds promptly to abnormal power consumption.
Similarly, The Gas Insulated Switchgear (GIS) is also a key player in power systems. Unlike the RMU, which often uses air or SF6 - filled compartments in a more compartmentalized design, GIS fully encapsulates high - voltage components in a sealed, SF6 - filled enclosure. This design offers higher insulation levels and space efficiency, making it ideal for high - voltage and compact installations, such as in densely populated urban areas or large - scale power transformation projects. GIS can handle higher current and voltage levels, providing more reliable protection and control. It's particularly suitable for scenarios where space is limited but high - performance power distribution is required, complementing the RMU's role in diverse power system applications.
Components of the Ring Main Unit
- Enclosure and Gas Management System: GIS enclosures, made of aluminum alloy or stainless steel, seal high-voltage components, creating a space for SF6 gas. This protects against external impacts and contaminants. The gas filling system allows for easy gas handling, while sensors monitor SF6 pressure, density, and purity. Alarms trigger when gas levels drop, ensuring insulation and arc - extinguishing performance.
- Busbar Chamber: Located centrally, the busbar chamber houses three - phase aluminum or copper busbars, treated to reduce resistance. Isolated by pot - type insulators, it collects and distributes power, with busbars running through the entire GIS to supply various branches.
- Swtichgaer Chamber: This chamber combines circuit breaker, disconnector, and earthing switch functions. SF6 circuit breakers quickly interrupt circuits, disconnectors create a clear break, and earthing switches ground the system during maintenance. All switches interlock to prevent misoperation.
- Transformer Chamber: The Transformer chamber contains current and voltage transformers. Current transformers convert high currents for measurement and protection, while voltage transformers provide low - voltage signals for monitoring and metering. Both are in SF6 - filled compartments.
- Low-voltage Control Room (Interlocking Low-voltage Chamber): It also functions as a control panel. Inside, there are a spring operating mechanism and a mechanical interlocking device (with a position indicator). It can also be equipped with auxiliary contacts, trip coils, emergency tripping mechanisms, capacitive live display devices, key locks, and electric operating devices. In addition, this space can also be used for the installation of control circuits, recording instruments, and protection relays, realizing the monitoring, control, and protection of the operating status of the ring main unit.
Prodcuct Description
NSRM - 12 - X / X X X
1 2 3 4 5 6
Main technical parameters
| Item |
Unit |
Argument |
| Rated Voltage |
kV |
12,24,33 |
| Rated Frequency |
Hz |
50 |
| Rated Current of main bus/Maximum rated current of fuse |
A |
630,125 |
| Rated short time withstand current of main circuit and ground circuit |
kA/S |
203 |
| Rated peak withstand current of main loop and ground loop |
kA |
50 |
| Rated short-circuit closing, current of main circuit and ground circuit |
kA |
50 |
| Number of full capacity breaks of load switch |
time |
100 |
| Fuse breaking current |
kA |
31.5,40 |
| Rated closed-oop breaking current |
A |
630 |
| Rated transfer current |
A |
1600 |
| Mechanical life |
time |
2000 |
| 1 min power frequency withstand voltage (peak) Relative, ground/isolated fracture |
kV |
42,48 |
| Lightning impulse withstand voltage (peak) phase to phase, ground/isolation fracture |
kV |
75,85 |
| Secondary circuit lmin power frequency voltage |
kV |
2 |
| Protection level |
|
IP3X,
Customized |
Normal Service Condition
Temperature range: -25°C to +40°C
Altitude: below 2000m (high-altitude products can be customized)
Humidity: not exceeding 90% (at 20°C), and not exceeding 50% at the highest temperature of +40°C.
Installation should be in a location free of severe vibrations, and the surrounding air should not be contaminated with corrosive gases, flammable gases, or significant amounts of water vapor.
Main Product
We were established on April 9, 2002, located in Yuanjiatai Industrial Park, Xin 'andu Street, Dongxihu District, Wuhan City. We are an electrical manufacturing enterprise integrating manufacturing, production and trade. The company specializes in the research and development, manufacturing and service of high and low voltage switchgear, capacitance compensation equipment, box-type substation, outdoor ring cage, dense busbar trough and other products. In 2003, we are certified to ISO9001, ISO45001 and SO14001. In 2021, we were approved as the Hubei Province High-tech Enterprise. Between 2002 and 2003 we obtained the Wuhan City "contract and credit" enterprise, with a total of 12 new patented technologies, the main products obtained the national compulsory product 3C certifcation and type test report. In recent years, the company's products have been widely used in power, real estate chemical and other industries, and have been unanimously recognized by users. The company always adhere to the "quality of truth", "striving to perfection" attitude to serve the user, with its core value "integrity, win-win" we gain deep insights into our customers' business requirements. We continuously develop high-quality products and create benchmark projects to consistently deliver greater power to the world!
Are you a factory or a trading company?
We are a professional factory engaged in the manufacture of complete sets of equipment for the power industry. We are also one of the high-quality suppliers of the State Grid Corporation of China.
Can you provide customized product services?
Our professional technical team will design products according to your drawing requirements and actual conditions. We can also provide OEM/ODM services.
How long is your production lead time?
It depends on the product requirements and quantity. Generally it takes 5-10 days.
How to confirm payment?
We accept wire transfer, Paypal and other payment methods. Our payment terms are 30% T/T advance payment and 70% final payment.
How is your after-sales service?
We will provide installation instructions and have a professional production and installation team to provide online installation guidance. If any problem occurs, please provide on-site photos and instrument information. We will respond as quickly as possible and provide a suitable solution within 1 day.
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