12kV/17.5kV/24kV New Compact Gas Insulated Ring Main Unit

Applications

The traditional 12kV/17.5kV/24kV primary distribution network is mainly arranged as a radial network, or arranged as a combination of radial and tree network. Since many users are connected in “T” form to a power line, any maintenance or fault on the power line will make all the users connected suffering power off. Power supply system is not reliable enough. Today, ring power supply systems are helping to improve reliability and widely used in secondary distribution networks.

SecoRMU is such a kind of medium voltage switch gear used in ring power supply network. With the features of completely sealed, modular design, flexible combination and extension, SecoRMU provides integrated solutions for most switching applications in urban-rural power cable upscale, power distribution network, wind farm, industry, O&G, underground installation, as well as municipal construction, commercial buildings, residential and other construction field.

Operating conditions

Normal operating conditions

The switch gears are fundamentally designed for the normal services conditions for indoor switch gears to IEC 60694.

• Ambient temperature
  • Maximum : +40 degree Celcius
  • Minimum : - 25 degree Celcius
• Humidity
  • Max daily average relative humidity : 95%
  • Max monthly average relative humidity : 90%
• The maximum site altitude is 1000m above sea level
• Seismic intensity : 8 degree
  • Horizontal acceleration : 0.25g
  • Vertical acceleration : 0.15g

Special operating conditions

4000m high altitude is available. Special operating conditions,  please contact GE.

In accordance with IEC60694, the manufacturer and end-users must agree about special operating conditions which deviate from operation under normal conditions. The manufacturer/supplier must be consulted in advance if especially severe operating conditions are involved.

SecoRMU is designed for use in the following applications :

• Power Grid
• Industrial Power Supply
• Compact secondary substations
• Wind power plants
• Commercial buildings
• Mining applications
• Airports
• Railway systems
• Underground installations

Features & Benefits

Modular, Compact, High performance

SecoRMU gas insulated ring main unit is a compact, modularized,  extendable or fixed gas insulated ring main unit with all the primary conductive system sealed in a stainless SF, gas tank, providing customers a safe reliable, high-performance and very low maintenance product.

Small and Compact

SecoRMU uses vacuum circuit breaker and adopts SF₆ gas as the insulated medium in the gas tank. SF₆ has strong electronegativity and excellent dielectric insulating performance. Its insulating strength is about 2-3 times of air in uniform electric field. The excellent insulating performance of SF₆ gas Maintenace free helps SecoRMU to realize small and compact structure, as well as safety and reliability.

Fully Modular Design/ Free Extendable

The basic functional module units K, T, V, B, C have uniform dimensions: 350x800x1380mm (widthxdepthxheight). Convenient for system design, and realize flexible replacement and upgrading. Each unit can extend to the left or right freely. Special designed busbar connectors make the combination and extension of SecoRMU switch gear simple, safe and reliable.

Big cable compartment also ensures convenient cable installation and connection.

Safe and Reliable

Both the gas tank and cable compartment is internal arc classified (20kA/1s), in order to ensure maximum personal safety.

Three position switch for natural interlocking.

Environment Independent / Maintenance Very Low

SecoRMU is environment independent because its primary conductive system is fully sealed in the SF₆ gas tank and will not be influenced by the outside world. Its sealing is systematically checked by automatic helium leakage detection process at the factory, ensuring less than 0.1% annual leakage rate. The gas tank passed water immersed test, reaching IP67 protection grade.

Besides, SecoRMU realizes no clearance splicing for installing an extension, independent of the impact of dew, dust, salt fog, small animals, chemical substances, etc.

Therefore, SecoRMU reaches very low maintenance and can be used under various severe operating conditions.

Advanced and Integrated Solutions

Adopting international advanced design, manufacturing and testing process, SecoRMU series ring main units have simple structures, flexible operations and reliable interlocks.

With the advanced sensor technology and up-to-date microcomputer protection relay, SecoRMU provide integrated solutions to meet different requirements if the users.