As a professional air-insulated ring main unit manufacturer, we offer the CKAS-12 Series Eco-Friendly Gas-Insulated Ring Main Unit(RMU) . The product uses dry air as the insulating medium and adopts a vacuum interrupter for arc extinction. The disconnecting switch and the vacuum interrupter are fully enclosed in a stainless steel tank filled with the environment-friendly gas.

The gas tank is made of imported stainless steel sheets and welded using advanced robotic welding technology. The protection rating of the gas-filled enclosure reaches IP67. The busbar supports both top expansion and side expansion, offering mature technology, easy installation, eco-friendly performance, safety and reliability, compact structure, maintenance-free operation and long service life.

Featuring high-tech core components, new technologies, advanced processes and new materials, this product is a fully eco-friendly switchgear solution. Its main functional unit is the V unit, also known as the circuit breaker unit.

1. Green environmental protection: The product uses dry air as the insulating medium and adopts vacuum arc extinction technology without the use of SF₆ or other harmful gases, ensuring environmentally friendly and safe operation. After the end of its service life, the dry air can be directly discharged into the atmosphere without gas recovery treatment, providing a simple, energy-saving and pollution-free solution.

2. Safety: Safety: All primary high-voltage components are sealed in stainless steel gas box, fully insulated and sealed, with protection grade IP67 and overall maintenance-free design; The main loop does not adopt solid sealing technology, which is beneficial to product heat dissipation and will not produce partial discharge problems and hidden dangers; The switch is equipped with an isolating switch observation window and LED lamp illumination, and the fracture of the isolating switch is clearly visible, thus improving the safety of product maintenance.

3. Intelligentization: With a high level of intelligent design, the product meets the requirements of smart grids and supports intelligent operation and maintenance for State Grid and China Southern Power Grid applications.

4. Stable and reliable: Through electric field simulation, calculation and optimization, the product achieves superior electrical performance, with partial discharge below 10 pC. With a micro-positive pressure of 0.02 MPa inside the gas tank, the product effectively prevents moisture, dust and salt mist from entering the enclosure. It is suitable for harsh operating environments such as high-altitude areas up to 5,000 meters, cold regions, humid low-lying areas, coastal high-salt-mist areas and strong sandstorm regions.

5. Compact structure: The product features a unit-based design with optional side expansion or top busbar expansion, making installation, expansion and unit replacement more flexible and convenient. With a compact structure and lightweight design, it is easy to transport, install and replace. The overall dimensions are 420 mm W × 900 mm D × 2000 mm H. It supports both upper disconnector with upper earthing switch and lower disconnector with lower earthing switch structures, meeting the standardized design requirements of State Grid and China Southern Power Grid.

Serial Number	Name			Unit	Parameter
					CKAS-12/V
1	rated voltage			kV	12
2	rated frequency			Hz	50
3	rated current			A	630
4	Rated insulation level	1min power frequency withstand voltage	Ground and interphase	kV	42
			fracture	kV	48
		Rated lightning impulse withstand voltage	Ground and interphase	kV	75
			fracture	kV	85
5	Rated closed-loop interrupting current			A	/
6	Rated cable charging breaking current			A	25
7	Rated short-circuit breaking current			kA	25
8	Rated short-term withstand current			kA	25
9	Rated peak withstand current			kA	63
10	Rated short-circuit closing current (peak value)			kA	63
11	Rated transfer current			A	/
12	Rated AC current			A	/
13	mechanical life			Time	10000
14	Mechanical life of disconnector and earthing switch			Time	3000
15	loop resistance			μΩ	≤150
16	Gas rated pressure (20℃ gauge pressure)			Mpa	0.02
17	Protection grade of closed inner shell			/	IP67
18	Enclosure protection grade			/	IP4X
19	Moisture content in dry air			ppm	≤150
20	Annual gas leakage rate			/	≤0.1%