1. The solid insulated switchgear is a fully enclosed medium-voltage equipment cast by epoxy resin. It is suitable for rail transit, urban distribution network, photovoltaic energy storage, data centers and harsh working conditions of high humidity and salt spray. 2. Rated voltage 7.2kV/12kV/24kV, 50/60Hz; bus current 630A-2500A, short-term withstand current up to 40kA/4s. 3. The main circuit conductor and insulating parts are integrated by vacuum casting, fully enclosed with no exposed live parts, and the cabinet protection grade is IP67, complying with IEC 62271 standards. 4. It comes standard with a complete five-proof mechanical interlock, with the interlock and unlock function of the grounding switch, and optional internal arc pressure relief protection to ensure safe operation and maintenance. 5. Does not rely on gas insulation, no risk of gas leakage, low partial discharge level, aging and weather resistance, maintenance-free whole machine, and strong environmental adaptability. 6. Modular unit design supports flexible combination of incoming, outgoing, bus coupler, PT, and grounding cabinet functional units. 7. The cabinet layout size can be adjusted according to the customer's single-line diagram, and intelligent monitoring functions such as partial discharge monitoring and remote measurement and control can be expanded. 8. Provide a full set of type test reports, technical drawings, remote after-sales support and OEM customization services.

Solid Insulated Switchgear for Medium-Voltage Distribution — Fully Enclosed, Gas-Free, IP67 Solution

DSY Switchgear's Solid Insulated Switchgear is a fully enclosed, epoxy-resin-cast medium-voltage solution rated at 7.2kV / 12kV / 24kV, with bus current from 630A to 2500A and short-time withstand current up to 40kA/4s. All live parts — including the vacuum interrupter and busbars — are vacuum-cast into solid insulation, achieving IP67 protection with no exposed conductors and no reliance on SF6 gas. Compliant with IEC 62271-200, IEC 62271-100, GB/T 11022, and GB/T 3906, this switchgear is designed for environments where reliability, safety, and low maintenance are non-negotiable.

What Makes Solid Insulation Different from Conventional Switchgear?

Traditional air-insulated or SF6 gas-insulated switchgear carries well-known risks — gas pressure fluctuations, leakage of toxic decomposition products, and sensitivity to humidity or altitude changes.

Solid Insulated Switchgear eliminates all of these vulnerabilities. The main circuit conductor and insulating parts are integrated through vacuum casting, forming a monolithic, fully sealed structure. There are no gas-tight tanks to maintain and no risk of dielectric strength loss due to pressure drops.

This makes it fundamentally more stable in demanding, real-world environments — from coastal substations to underground data centers.

Product Applications

Technical Specifications

Parameter	Value
Rated Voltage	7.2kV / 12kV / 24kV
Rated Frequency	50Hz / 60Hz
Rated Bus Current	630A – 2500A
Rated Short-Time Withstand Current	20 / 25 / 31.5 / 40kA (4s)
Circuit Breaker Type	Vacuum Circuit Breaker
Shell Protection Grade	IP43 / IP67
Insulation Method	Solid insulation, epoxy resin casting — no gas insulation
Structure	Fully enclosed, integrated casting
Applicable Standards	IEC 62271-200, IEC 62271-100, GB/T 11022, GB/T 3906

Certifications

Core Technical Advantages

No gas dependency. Without SF6 gas, you eliminate the risk of leakage, toxic decomposition, and pressure-related dielectric instability. The partial discharge level stays consistently low, and insulation performance remains stable over decades.

Fully enclosed with IP67 protection. The epoxy resin casting creates a continuous barrier around every live component. This means no exposed conductors, no risk of electric shock during operation or maintenance, and complete immunity to contaminants like moisture, dust, and salt spray.

Five-proof mechanical interlock as standard. Every unit ships with a complete five-proof interlock system, including grounding switch interlock and unlock functions. Optional internal arc pressure relief protection is also available — giving your team multiple layers of operational safety.

Maintenance-free design. Because the insulation is solid and sealed, there are no consumables to replace, no gas to monitor, and no annual inspection routines tied to insulation degradation. Long-term operating costs are significantly lower than gas-insulated alternatives.

Where Is It Applied?

The IP67-rated, gas-free design makes this switchgear a practical choice across a wide range of demanding applications:

Rail transit and urban distribution networks benefit from the compact, fully sealed enclosure that handles vibration, humidity, and close-proximity installation without performance compromise.

Photovoltaic and energy storage systems require switchgear that can endure frequent load cycling and outdoor or semi-outdoor conditions — both of which this design handles reliably.

Data centers and commercial buildings value the SF6-free, explosion-proof nature of solid insulation. In densely occupied environments, eliminating toxic gas risk is a mandatory safety requirement, not just a preference.

High-humidity and coastal regions are where the IP67 protection truly demonstrates its value. Salt spray corrosion and tracking flashovers — common failure modes in traditional switchgear — are structurally prevented by the epoxy encapsulation.

Exhibitions

Quality Control and Verification

Each unit undergoes rigorous testing before delivery. Key inspection procedures include:

Partial Discharge (PD) Testing — verifies that no internal voids or impurities exist within the insulation, maintaining PD levels below 10pC at 1.1× rated voltage
Power Frequency Withstand Voltage Test — confirms insulation margin against overvoltage surges
Temperature Rise Test — validates effective heat dissipation under full-load conditions
Mechanical Endurance Test — validates the vacuum circuit breaker for 10,000 operational cycles
X-ray Non-Destructive Testing — detects micro-cracks or bubbles within the epoxy encapsulation

A full set of type test reports and technical drawings is provided with every order.

Customization and Smart Monitoring Options

Every project has different layout requirements, and the modular unit design supports flexible combinations of incoming, outgoing, bus coupler, PT, and grounding cabinet functional units.

Cabinet layout dimensions can be adjusted directly to match your single-line diagram. You can also expand intelligent monitoring capabilities — including partial discharge monitoring, remote measurement, and remote control — making the system fully compatible with smart grid and IEC 61850 digital substation requirements.

OEM customization services are available for buyers who require branded configurations or project-specific modifications.

Packaging & Shipping

FAQ

Q1: What insulation method is used, and what are the main advantages?

A: Epoxy resin vacuum casting integrates the main circuit conductor and insulation parts into a single sealed unit. This eliminates gas leakage risk, keeps partial discharge levels low, and maintains stable insulation performance over the long term.

Q2: What protection grade does this switchgear achieve?

A: The cabinet reaches IP67 — fully enclosed with no exposed live parts. This makes it suitable for high-humidity, salt spray, and other harsh operating environments.

Q3: What safety interlocks are included as standard?

A: A complete five-proof mechanical interlock system comes standard, including grounding switch interlock and unlock functions. Internal arc pressure relief protection is available as an option.

Q4: How does this compare to SF6 switchgear in terms of environmental impact?

A: This switchgear completely eliminates SF6 gas, which has a Global Warming Potential (GWP) thousands of times higher than CO₂. The solid insulation materials are also recyclable, supporting ESG compliance.

Q5: Is the switchgear suitable for smart grid integration?

A: Yes. Optional partial discharge monitoring, remote measurement, and remote control functions are supported, and the system is compatible with IEC 61850 digital protocols.

Q6: Can the layout be customized for my project?

A: Yes. Cabinet layout and dimensions can be adjusted according to your single-line diagram, and OEM customization services are available. Contact DSY Switchgear's team to discuss your project requirements.

Contact Us

Ready to specify or source this Solid Insulated Switchgear for your next project? Reach out at [email protected] — the DSY technical team is ready to support you.