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

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

Key attributes

Brand ROCKWILL
Model NO. 12kV 24kV 36kV 38.5kV Maintenance-Free Pure air/Nitrogen Insulated Ring Main Unit(RMU)
Rated voltage 36kV
Rated normal current 630A
Rated frequency 50/60Hz
Series REC

Product descriptions from the supplier

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, 6.3kV, 6.6kV, 6.9kV, 7.2kV, 10kV, 10.5kV, 11kV, 11.5kV, 12kV, 13.2kV, 13.8kV, 14.5kV, 14.4kV, 15kV, 15.5kV, 15.6kV, 17.5kV, 20kV, 21.9kV, 22kV, 24kV, 30kV, 33kV, 33.5kV, 34.5kV, 35kV, 36kV, 38kV, 38.5kV, 40.5kV, 44kV, 45kV, 46kV, 66kV and 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

Type

Top extension of single panel

Side extension of single panel

Single panel size of compact module

Circuit Breaker Panel

390*850*1950

390*850*1950

390*850*1950

Load Break Switch Panel

390*850*1950

390*850*1950

390*850*1950

PT Panel (with 3phase, 5 columns)

600*850*1950

600*850*1950

600*850*1950

PT Panel (single phase)

420*850*1950

420*850*2000

420*850*1600

Bus Riser

375*850*1950

375*850*2000

375*850*1600

Metering panel

750*850*1950

750*850*2000

750*850*1600


Documentation Resource Library
Restricted
REC-12 Pure air/Nitrogen insulated ring main unit
Brochure
English
Consulting
Consulting
FAQ for
Q: How to deal with gas leakage in environmentally friendly cabinets?
A:
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.
Q: What is the service life of the insulating gas in environmentally friendly cabinets?
A:
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.
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On-time delivery rate
Response time
100.0%
≤4h
Company overview
Workplace: 108000m²m² Total staff: 700+ Highest Annual Export(usD): 150000000
Workplace: 108000m²m²
Total staff: 700+
Highest Annual Export(usD): 150000000
Services
Business Type: Design/Manufacture/Sales
Main Categories: High Voltage Electrical Apparatus/Electric transformer
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.

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