Maintenance-Free Pure air/Nitrogen Insulated RMU-12kV to 38.5kV

Attributes Description Documentation Resource Library

Key attributes

Brand	ROCKWILL
Model NO.	Maintenance-Free Pure air/Nitrogen Insulated RMU-12kV to 38.5kV
Rated voltage	36kV
Rated normal current	630A
Rated frequency	50/60Hz
Series	REC

Description

Description：

ROCKWILL attaches great importance to product quality and manufacturing technology, and treats every step of product production with precision and meticulousness. Only insulation gas is used to comprehensively compare heating dry air, nitrogen, carbon dioxide, and pure air. Pure air synthesized with extremely low moisture content and high purity is selected as the preferred insulation gas to replace SF6. The core switch unit of the product adopts a brand new vacuum arc extinguishing chamber soft package casting process, combined with a carefully designed rotating three-position switch, with a simple and compact overall structure; The fully sealed gas box replaces SF6 with pure air, with a highly advantageous electric field distribution design, and the partial discharge of the entire cabinet is below 5pC; The salt spray resistance test of the operating mechanism of the zinc inlay alloy surface treatment process has exceeded 168 hours, and the longest service life can reach 30000 times.

Feature：

Pure air/Nitrogen insulated ring main unit
Environmentally friendly gas
Zero carbon emissions, zero waste
Intensive and meticulous producing, Seeking finer quality
Comply with IEC/ANSI standards
Provided customized manufacture
Whole solutions for design, assembly, test...
Accountable solution for safety and reliability
Wide range offering, easy business and convenient installation

Main technical parameters (three phase)：

The voltage classes of some of these eco-friendly switchgears include 6kV to 69kV. and customization is available.

12kV

N	Item	Unit	Data
1	Rated maximum voltage	kV	12
2	Rated maximum current	A	630/1250
3	Rated frequency	Hz	50/60
4	Method of Arc Suppressing		Vacuum
5	Method of Insulation		Pure air/Nitrogen
6	Rated short circuit breaking current	kA	20/25
7	Rated peak value withstand current	kA	50/63
8	Rated 1min power frequency withstand voltage	kV	42
9	Rated lightning impulse voltage	kV	75
10	Operation sequence	/	C-0.3-CO-180-CO
12	Resistance loop	μΩ	≤140
13	Rated gas pressure (20℃ gauge)	Mpa	0.02
14	Minimum operating gas pressure	Mpa	0
15	Mechanical life - Circuit breaker	N	10000
	Mechanical life - Load break switch	N	3000/6000
	Mechanical life - Disconnector	N	3000/6000
	Mechanical life - Earthing switch	N	3000/6000
16	Protection grade - Gas tank		IP67
	Protection grade - Shell		IP4X
17	Rated annual air leakage rate	%	0.01

24kV

N	Item	Unit	Data
1	Rated maximum voltage	kV	24
2	Rated maximum current	A	630/1250
3	Rated frequency	Hz	50/60
4	Method of Arc Suppressing		Vacuum
5	Method of Insulation		Pure air/Nitrogen
6	Rated short circuit breaking current	kA	20/25
7	Rated peak value withstand current	kA	50/63
8	Rated 1min power frequency withstand voltage	kV	42
9	Rated lightning impulse voltage	kV	75
10	Operation sequence	/	C-0.3-CO-180-CO
12	Resistance loop	μΩ	≤140
13	Rated gas pressure (20℃ gauge)	Mpa	0.02
14	Minimum operating gas pressure	Mpa	0
15	Mechanical life - Circuit breaker	N	10000
	Mechanical life - Load break switch	N	3000/6000
	Mechanical life - Disconnector	N	3000/6000
	Mechanical life - Earthing switch	N	3000/6000
16	Protection grade - Gas tank		IP67
	Protection grade - Shell		IP4X
17	Rated annual air leakage rate	%	0.01

36kV

N	Item	Unit	Data
1	Rated maximum voltage	kV	36
2	Rated maximum current	A	630/1250
3	Rated frequency	Hz	50/60
4	Method of Arc Suppressing		Vacuum
5	Method of Insulation		Pure air/Nitrogen
6	Rated short circuit breaking current	kA	20/25
7	Rated peak value withstand current	kA	50/63
8	Rated 1min power frequency withstand voltage	kV	42
9	Rated lightning impulse voltage	kV	75
10	Operation sequence	/	C-0.3-CO-180-CO
12	Resistance loop	μΩ	≤140
13	Rated gas pressure (20℃ gauge)	Mpa	0.02
14	Minimum operating gas pressure	Mpa	0
15	Mechanical life - Circuit breaker	N	10000
	Mechanical life - Load break switch	N	3000/6000
	Mechanical life - Disconnector	N	3000/6000
	Mechanical life - Earthing switch	N	3000/6000
16	Protection grade - Gas tank		IP67
	Protection grade - Shell		IP4X
17	Rated annual air leakage rate	%	0.01

Compact type pure air/nitrogen insulated ring main unit

12kV 24kV 36kV 38.5kV Maintenance-Free Pure air/Nitrogen Insulated Ring Main Unit(RMU)

Type	Top extension of single panel	Side extension of single panel	Single panel size of compact module
Circuit Breaker Panel	3908501950	3908501950	3908501950
Load Break Switch Panel	3908501950	3908501950	3908501950
PT Panel (with 3phase, 5 columns)	6008501950	6008501950	6008501950
PT Panel (single phase)	4208501950	4208502000	4208501600
Bus Riser	3758501950	3758502000	3758501600
Metering panel	7508501950	7508502000	7508501600

12kV 24kV 36kV 38.5kV Maintenance-Free Pure air/Nitrogen Insulated Ring Main Unit(RMU)

Solutions for RMU

Rockwill Medium-Voltage SF6-Free Gas-Insulated Switchgear Series – From RMR to REC and RAR

Within Rockwill's SF6-free product portfolio, the RMR, REC, and RAR series all adopt gas-insulated, hermetically sealed structures that fully enclose high-voltage live parts in stainless steel tanks, ensuring complete sealing and maintenance-free operation. The three series share a similar modular design philosophy, but differ significantly in insulation medium, technical positioning, voltage coverage, and application scenarios.Core DifferencesIn terms of insulation medium and environmental char

Rockwill

Documentation Resource Library RMU

Restricted.

REC-12 Pure air/Nitrogen insulated ring main unit

Catalogue

English

Consulting

Public.

REC-12 Ring Main Unit FLYER

Brochure

English

PDF

FAQ for RMU

Q: What is the service life of the insulating gas in environmentally friendly cabinets?

Under normal sealing conditions, the service life of insulating gas (dry air, N2, N2/CO2 mixture) is 10-15 years. It mainly depends on the cabinet's sealing performance and operating environment. In humid or corrosive environments, the seal may age faster, shortening the gas service life. Regular maintenance (e.g., annual pressure and dew point checks) can extend the effective service life of the gas.

Q: How to deal with gas leakage in environmentally friendly cabinets?

First, use a gas detector to locate the leakage point (focus on seals, valves, and flange connections). For minor leaks, replace the sealing ring or tighten the fasteners. For major leaks, empty the remaining gas (directly discharge eco-friendly media like dry air/N2), repair the leakage point, and refill with qualified insulating gas after confirming the seal. Regularly check the gas pressure gauge and dew point monitor to prevent leakage in advance.

Negotiable

Pricing calculator

Model

REC-12 Ring Main Unit FLYER

Warranty by

Whole life care manager

Whole-life care management services for equipment procurement, use, maintenance, and after-sales, ensuring safe operation of electrical equipment, continuous control, and worry-free electricity consumption.

The equipment supplier has passed platform qualification certification and technical evaluation, ensuring compliance, professionalism, and reliability from the source.

Type	Top extension of single panel	Side extension of single panel	Single panel size of compact module
Circuit Breaker Panel	3908501950	3908501950	3908501950
Load Break Switch Panel	3908501950	3908501950	3908501950
PT Panel (with 3phase, 5 columns)	6008501950	6008501950	6008501950
PT Panel (single phase)	4208501950	4208502000	4208501600
Bus Riser	3758501950	3758502000	3758501600
Metering panel	7508501950	7508502000	7508501600