1. SF6 gas insulated switchgear is a fully sealed metal inflatable medium-voltage equipment, suitable for urban underground substations, rail transit, data centers, industrial and commercial parks and power distribution scenarios with limited space. 2. Rated voltage 7.2kV/12kV/24kV/40.5kV, 50/60Hz; bus current 630A-3150A, short-term withstand current up to 50kA/4s. 3. Equipped with built-in vacuum circuit breaker/load switch, fully sealed SF6 gas box, cabinet enclosure protection grade IP65, in line with IEC 62271 standard. 4. It comes standard with complete five-proof mechanical interlocking, integrated SF6 gas pressure monitoring and alarm lockout, and optional internal arc pressure relief protection to ensure operator safety. 5. SF6 gas insulation, the cabinet is compact and occupies a small area. It is not affected by external dust, humidity, and salt spray environments, and the whole machine has a long maintenance-free period. 6. Modular interval design supports flexible combination and expansion of incoming line, outgoing line, bus coupler, PT, grounding, and capacitor cabinet functional units. 7. The interval configuration can be customized according to the customer's one-line diagram, and it supports the expansion of gas status monitoring, partial discharge, and remote intelligent monitoring functions. 8. Provide a full set of type test reports, technical drawings, remote technical support and OEM/ODM customization services.

PV Ring Main Unit (RMU) for Solar Power Systems — Fully Sealed, Low Maintenance, Built for Harsh Environments

Tailored exclusively for medium-voltage power distribution in photovoltaic power stations, DSY Switchgear’s PV Ring Main Unit (RMU) serves as stable grid connection equipment between step-up transformers and main collector lines. Covering rated voltages from 7.2kV to 40.5kV, bus current of 630A to 3150A and a maximum 4s short-time withstand current of 50kA, this fully sealed SF6 insulated switchgear fully complies with IEC 62271-200 international standards. With IP65 high-level enclosure protection, it adapts to desert, coastal, underground substation and space-limited solar project scenarios. Backed by over 60 technical patents and qualified supplier credentials for State Grid and China Southern Power Grid, DSY delivers highly reliable and low-maintenance power distribution solutions for global photovoltaic projects.

What Makes This Switchgear the Right Choice for PV Applications

DSY PV Ring Main Unit (RMU) is professionally developed for the pain points of photovoltaic power distribution scenarios. The fully sealed SF6 gas tank structure completely isolates internal core components from external dust, moisture and salt spray corrosion, maintaining stable equipment performance throughout the service life. It can operate continuously and stably in various harsh environments such as deserts, coastal areas and floating photovoltaic platforms to ensure uninterrupted power collection and transmission.

In addition, the compact modular structure effectively reduces the overall floor area of the equipment. It cuts down project civil construction investment and land occupation costs, helping customers optimize BOS costs and accelerate the construction and commissioning progress of centralized and distributed photovoltaic projects.

Product Applications

Technical Specifications

Parameter	Value
Rated Voltage	7.2kV / 12kV / 24kV / 40.5kV
Rated Frequency	50Hz / 60Hz
Rated Bus Current	630A – 3150A
Rated Short-Time Withstand Current	20 / 25 / 31.5 / 40 / 50 kA (4s)
Switching Device	Built-in vacuum circuit breaker / load switch
Insulating Medium	SF6 gas
Enclosure Protection Grade	IP43 / IP65
Applicable Standards	IEC 62271-200, IEC 62271-100, GB/T 11022, GB/T 390
Structure	Fully sealed SF6 gas box, modular spacer design

Certifications

Key Product Features

Fully Sealed SF6 Gas Insulation

The whole equipment adopts an integrated fully sealed SF6 gas tank structure, which completely avoids the influence of external humid air, dust and corrosive substances. The annual SF6 gas leakage rate is controlled below 0.1%, realizing long-term maintenance-free operation without performance attenuation.

High Environmental Adaptability

With optional IP65 high-standard protection grade, the cabinet is suitable for underground substations, high-humidity coastal areas, high-altitude regions and dusty desert environments. It supports a wide operating temperature range of -40°C to +70°C, adapting to extreme climate changes in various photovoltaic project sites.

Complete Five-Proof Mechanical Interlocking

The product is equipped with a standard complete five-proof mechanical interlock system. It forms a strict logical interlock for switching, closing and grounding operations, effectively preventing on-site misoperation and greatly improving the safety of daily operation and maintenance work.

Integrated SF6 Gas Pressure Monitoring

Built-in high-precision gas pressure monitoring module supports real-time data monitoring, automatic alarm and safety locking functions. Once the gas pressure is lower than the safe threshold, the equipment will automatically lock to avoid operation risks caused by insufficient insulation performance.

Optional Internal Arc Protection

To meet the high safety requirements of confined installation spaces such as underground substations, optional internal arc pressure relief protection is available. It can quickly release pressure and dissipate heat in case of internal faults, minimizing equipment damage and personnel safety risks.

Modular Design for Flexible PV System Configuration

Different photovoltaic power stations have different substation topological structures. This PV Ring Main Unit (RMU) adopts a flexible modular interval design, supporting free combination and expansion of multiple functional units including incoming line, outgoing line, bus coupling, PT measurement, grounding and capacitor modules.

We can customize the interval configuration scheme strictly according to customers’ one-line diagrams, avoiding redundant configuration or function deficiency of standard equipment, and perfectly matching the actual power distribution demands of various photovoltaic projects.

The equipment reserves intelligent upgrade interfaces, which can be expanded with SF6 gas status monitoring, partial discharge detection and DTU remote communication modules. It supports seamless docking with SCADA monitoring systems, fully adapting to the construction requirements of smart photovoltaic power stations and digital substations.

Exhibitions

Application Scenarios

Utility-Scale Ground-Mounted PV Plants

Large-scale ground photovoltaic power stations are mostly built in deserts and open areas with strong solar radiation and heavy dust. The fully sealed structure and wide temperature adaptation range ensure stable power output and reduce frequent on-site maintenance work.

Commercial and Industrial (C&I) Rooftop Systems

Factory and commercial building rooftop photovoltaic projects have limited installation space. The compact and lightweight modular design saves installation space, while high safety and stability ensure long-term reliable grid-connected operation of rooftop power generation systems.

Floating Photovoltaic (FPV) Stations

Floating photovoltaic platforms face long-term high humidity and water vapor corrosion risks. The IP65 sealed enclosure effectively resists environmental corrosion, maintaining stable operation of power collection systems on the water surface for a long time.

Quality Assurance and Documentation

All equipment undergoes comprehensive and rigorous full-performance testing before delivery. The inspection items cover dielectric withstand test, lightning impulse withstand test, helium mass spectrometry leakage detection, more than 1000–2000 times of mechanical endurance tests, partial discharge detection and salt spray corrosion resistance test, to fully verify equipment stability and environmental adaptability.

Each order is delivered with complete type test reports and professional technical drawings. We support personalized OEM/ODM customized services and provide full-cycle remote technical after-sales support to meet differentiated project construction needs.

Packaging & Shipping

Frequently Asked Questions

Q1: What insulating medium does this PV RMU adopt?

A: It takes SF6 gas as the core medium for insulation and arc extinction. The fully sealed gas tank structure delivers stable insulation performance and excellent arc-extinguishing capability throughout the equipment service life.

Q2: What is the maximum protection grade of the cabinet?

A: The enclosure supports IP43 and IP65 optional protection grades. The IP65 version provides full dust prevention and water jet resistance, suitable for harsh outdoor and underground working environments.

Q3: What standard safety configurations does the equipment have?

A: It is equipped with standard five-proof mechanical interlock and integrated SF6 gas pressure monitoring with alarm and locking functions. Optional internal arc pressure relief protection is available for higher safety requirements.

Q4: Does it support intelligent remote monitoring?

A: Yes. It can be expanded with DTU intelligent monitoring modules to realize real-time remote monitoring of gas pressure, operating status and partial discharge data, supporting SCADA system docking.

Q5: What is the daily maintenance cycle of the switchgear?

A: Benefiting from the fully sealed maintenance-free design, only simple visual inspection of the cabinet and line connections is required every 2–5 years, greatly reducing operation and maintenance costs.

Q6: Is project-specific structural customization supported?

A: Absolutely. We can customize the internal interval combination and overall configuration strictly according to your one-line diagram, adapting to all types of photovoltaic substation topological structures.

Contact DSY Switchgear

If you are in need of high-stability, anti-corrosion and low-maintenance PV Ring Main Unit (RMU) for your photovoltaic power projects, please feel free to contact our professional technical team for detailed product parameters, project customization solutions and accurate quotations. Email us at [email protected].