• Product
  • Suppliers
  • Manufacturers
  • Solutions
  • Free tools
  • Knowledges
  • Experts
  • Communities
Search


17.5kV 20kV 21.9kV 24kV Solid Insulation Ring Main Unit/ distribution board

  • 17.5kV 20kV 21.9kV 24kV Solid Insulation Ring Main Unit/ distribution board

Key attributes

Brand ROCKWILL
Model NO. 17.5kV 20kV 21.9kV 24kV Solid Insulation Ring Main Unit/ distribution board
Rated voltage 24kV
Rated frequency 50/60Hz
Series GMSS

Product descriptions from the supplier

Description
Description

Pioneer in China's eco-friendly switchgear sector, we have specialized in R&D and manufacturing of SF₆-free switchgear for decades. With core technologies, we have established industry standards. Boasting a fully independent end-to-end production chain, we have built a product matrix of zero-emission and high-reliability eco-friendly switchgear, making us a trusted choice for power grid construction.

It is mainly composed of three functional units, namely circuit breaker unit, load switch, and combined electrical unit. Each unit can be used alone or can be freely expanded. Its structure is divided into intelligent control instrument room, operating mechanism and primary part.

The solid insulation ring main unit is a device that uses solid insulating materials as the main insulating medium. After the main conductive circuits such as conductive connection, isolating switch, grounding switch, main busbar, branch busbar, etc. are single or combined, they are encapsulated into one or several combinations or modules with solid insulating medium.

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.

Feature

  • High-efficiency solid insulation performance: Uses high-quality solid insulating materials such as epoxy resin to encapsulate high-voltage components. The insulation strength is adapted to medium-voltage levels (e.g., 12kV, 24kV), and it is not affected by environmental factors like humidity and dust, significantly reducing the risks of flashover and breakdown, and ensuring long-term stable operation of the equipment.

  • Eco-friendly gas-free design: No need to use greenhouse gases such as SF₆, fundamentally avoiding environmental hazards caused by gas leakage. It conforms to the global trend of green energy development, and is especially suitable for ecologically sensitive areas and scenarios with strict environmental protection requirements.

  • Compact structure and space adaptability: Combining a metal-enclosed shell with a modular design, it has a small volume and a small footprint, making it easy to install in space-constrained places such as urban distribution stations and commercial building switchrooms, and improving site utilization.

  • Multiple safety protections: Equipped with complete mechanical and electrical interlocking devices to prevent misoperations (such as on-load switching and entry into live compartments); the fully enclosed metal shell effectively shields the high-voltage electric field, combined with the live display function, to comprehensively ensure operation and maintenance safety.

  • Low maintenance and long service life: The solid insulating material has strong stability, and internal components are isolated from the outside, reducing corrosion and aging. It achieves long-term maintenance-free operation with a service life of more than 20 years, significantly reducing the whole-life-cycle cost.

  • Flexible power distribution compatibility: Supports multiple wiring methods such as ring network and radial type, and can be quickly connected with transformers, cables and other equipment of the same voltage level, adapting to diverse power distribution needs in urban power grids, industrial plants, new energy projects, etc.

Normal use conditions

  • Ambient air temperature: maximum 40°C, (average value within 24 hours shall not exceed 35°C), minimum -25°C.

  • Altitude: no more than 2000m (coordinate with the manufacturer when it exceeds 2000m).

  • Air humidity: the average daily relative humidity is not more than 95%, and the monthly average relative humidity is not more than 90%;

Note: Negotiate with our company when ordering with special conditions of use.

FAQ
Q: What are the key points to pay attention to during the maintenance of solid environmentally friendly cabinets?
A:
The core maintenance points include: 1) Regularly check the appearance of the solid insulation layer for cracks, deformation, discoloration or damage (especially focusing on conductor connections); 2) Avoid touching the insulation layer with sharp tools to prevent mechanical damage; 3) Monitor the temperature and humidity inside the cabinet to avoid high temperature and high humidity accelerating insulation aging; 4) Regularly test the insulation resistance to ensure that the insulation performance meets the standard; 5) Prevent the cabinet from being subjected to strong vibration or impact to avoid the insulation layer falling off.
Q: What key tests are required to verify the solid insulation performance of solid environmentally friendly cabinets?
A:
Core tests include five categories to ensure that insulation performance meets standards: 1) Dielectric strength test: Verify that the insulation layer has no breakdown or flashover under high voltage through power frequency withstand voltage and lightning impulse withstand voltage tests; 2) Partial discharge test: Monitor discharge signals inside and on the surface of the insulation layer to avoid partial discharge accelerating insulation aging; 3) Aging life test: Evaluate the long-term anti-aging ability of insulating materials through simulated environmental tests such as high-low temperature cycles and damp-heat aging; 4) Mechanical strength test: Simulate vibration and collision during transportation, installation and operation to verify the firmness of the connection between the insulation layer and conductors; 5) Pollution test: Conduct withstand voltage test in an artificial pollution layer environment to ensure insulation reliability in harsh scenarios such as dusty and humid conditions. All tests must comply with standards such as IEC 
Know your supplier
Online store
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.

Related Products

Related Knowledges

  • Impact of DC Bias in Transformers at Renewable Energy Stations Near UHVDC Grounding Electrodes
    Impact of DC Bias in Transformers at Renewable Energy Stations Near UHVDC Grounding ElectrodesWhen the grounding electrode of an Ultra-High-Voltage Direct Current (UHVDC) transmission system is located close to a renewable energy power station, the return current flowing through the earth can cause a rise in ground potential around the electrode area. This ground potential rise leads to a shift in the neutral-point potential of nearby power transformers, inducing DC bias (or DC offset) in their
    01/15/2026
  • HECI GCB for Generators – Fast SF6 Circuit Breaker
    1.Definition and Function1.1 Role of the Generator Circuit BreakerThe Generator Circuit Breaker (GCB) is a controllable disconnect point located between the generator and the step-up transformer, serving as an interface between the generator and the power grid. Its primary functions include isolating generator-side faults and enabling operational control during generator synchronization and grid connection. The operating principle of a GCB is not significantly different from that of a standard c
    01/06/2026
  • Distribution Equipment Transformer Testing, Inspection, and Maintenance
    1.Transformer Maintenance and Inspection Open the low-voltage (LV) circuit breaker of the transformer under maintenance, remove the control power fuse, and hang a “Do Not Close” warning sign on the switch handle. Open the high-voltage (HV) circuit breaker of the transformer under maintenance, close the grounding switch, fully discharge the transformer, lock the HV switchgear, and hang a “Do Not Close” warning sign on the switch handle. For dry-type transformer maintenance: first clean the porcel
    12/25/2025
  • How to Test Insulation Resistance of Distribution Transformers
    In practical work, insulation resistance of distribution transformers is generally measured twice: the insulation resistance between thehigh-voltage (HV) windingand thelow-voltage (LV) winding plus the transformer tank, and the insulation resistance between theLV windingand theHV winding plus the transformer tank.If both measurements yield acceptable values, it indicates that the insulation among the HV winding, LV winding, and transformer tank is qualified. If either measurement fails, pairwise
    12/25/2025
  • Design Principles for Pole-Mounted Distribution Transformers
    Design Principles for Pole-Mounted Distribution Transformers(1) Location and Layout PrinciplesPole-mounted transformer platforms should be located near the load center or close to critical loads, following the principle of “small capacity, multiple locations” to facilitate equipment replacement and maintenance. For residential power supply, three-phase transformers may be installed nearby based on current demand and future growth projections.(2) Capacity Selection for Three-Phase Pole-Mounted Tr
    12/25/2025
  • Transformer Noise Control Solutions for Different Installations
    1.Noise Mitigation for Ground-Level Independent Transformer RoomsMitigation Strategy:First, conduct a power-off inspection and maintenance of the transformer, including replacing aged insulating oil, checking and tightening all fasteners, and cleaning dust from the unit.Second, reinforce the transformer foundation or install vibration isolation devices—such as rubber pads or spring isolators—selected based on the severity of vibration.Finally, strengthen sound insulation at weak points of the ro
    12/25/2025

Related Solutions

  • Intelligent Operation Solution for 12kV Vacuum Circuit Breakers: Integrating Real-time Monitoring & Lifetime Optimization
    Ⅰ. Equipment Operation & MaintenanceIntelligent Monitoring System Integration​Multi-parameter Real-time Monitoring: Embedded sensors (temperature, displacement, Hall effect current sensors) track contact temperature rise, mechanical characteristics (opening/closing speed, overtravel), coil current, and partial discharge signals. Data undergoes preprocessing via edge computing prior to cloud upload.​Lifetime Prediction Model: Dynamically evaluates remaining lifespan using electrical wear data
    06/10/2025
  • SF6 Circuit Breaker Solutions for Outdoor Installation (Anti-Pollution & Seismic Resistance)
    I.Core Challenges in Outdoor Installation​In high-voltage transmission and distribution systems, SF6 circuit breakers are exposed to complex outdoor environments for extended periods, facing the following critical issues:​Pollution & Insulation Degradation​Dust, salt fog, and industrial pollutants in outdoor environments easily adhere to equipment surfaces. In coastal or industrial areas, pollution levels may reach ​Class IV, resulting in insufficient creepage distance and triggering ​flasho
    05/12/2025
  • 12kV Indoor Vacuum Circuit Breaker Southeast Asia Solution: Anti-Corrosion Compact Design
    12kV Indoor Vacuum Circuit Breaker Southeast Asia Solution: Anti-Corrosion Compact DesignⅠ. Executive Summary​Southeast Asia faces rapidly growing electricity demand alongside environmental challenges including high temperatures, humidity, salt spray corrosion, and grid instability. This solution recommends ​Solid Insulated Pole-Mounted Vacuum Circuit Breakers (VCB)​​ featuring ​high reliability, ​compact design, and ​smart monitoring. Tailored for tropical climates and industrial scenarios, it
    06/10/2025
Haven't found the right supplier yet? Let matching verified suppliers find you. Get Quotation Now
Haven't found the right supplier yet? Let matching verified suppliers find you.
Get Quotation Now
Send inquiry
Download
Get the IEE Business Application
Use the IEE-Business app to find equipment, obtain solutions, connect with experts, and participate in industry collaboration anytime, anywhere—fully supporting the development of your power projects and business.