
Medium Voltage Switchgear Manufacturer — Factory Direct Supply
12kV–40.5kV vacuum circuit breakers, gas-insulated switchgear, and metal-enclosed switchgear panels. IEC 62271 routine-tested, ISO 9001 / CE / CCC certified. 10,000+ units/year capacity with 30-day export lead time.
Complete Medium Voltage Product Range
From outdoor pole-mounted circuit breakers to intelligent indoor switchgear panels — a full spectrum of MV equipment covering 12kV to 40.5kV, manufactured in our own facility.
Vacuum Circuit Breakers
12kV / 24kV / 40.5kV — Indoor & Outdoor
Outdoor pole-mounted VCBs (ZW32, SPV series) and indoor VCBs (VN, CE, EVN series) with up to 50,000 mechanical operations life. SF6-free solid insulation technology.
Indoor Vacuum Circuit Breakers
12kV / 24kV / 40.5kV — Switchgear-Ready
Premium indoor VCBs from 12kV to 40.5kV with ultra-low resistance vacuum arc chambers, embedded pole APG epoxy insulation, and modular spring mechanisms.
Gas-Insulated Switchgear (GIS)
12kV Nitrogen & 40.5kV SF6 C-GIS
Eco-friendly nitrogen-insulated (GSN3-12) and SF6 gas-insulated (GSN1-40.5L) compact switchgear with stainless steel laser-welded enclosures. Maintenance-free sealed design.
Medium Voltage Switchgear Panels
12kV / 24kV / 40.5kV — ASN Series
Complete metal-enclosed switchgear panels (ASN3-12, ASN2-24, ASN1-40.5) with internal arc-resistant design, IP4X protection, and intelligent monitoring options.
SF6 Load Break Switches
12kV / 24kV — Outdoor Pole-Mounted
SPG series outdoor SF6 load break switches for distribution networks. Pressure-assisted arc blowing, 304 stainless steel housing, FTU compatible for automation.
Low Voltage Switchgear
SLVA Series — Up to 690V / 6300A
Grid-standardized low voltage switchgear with draw-out functional units. 8 standardized structural schemes for power distribution, motor control, and reactive power compensation.
Why Choose NAIJI as Your Switchgear Manufacturer
A vertically integrated manufacturer with in-house engineering, fabrication, assembly, and IEC 62271 routine testing — delivering reliable medium voltage equipment since 2001.
Sino-Korean Joint Venture Since 2001
Established as a joint venture between Chinese and Korean partners, combining 25 years of medium voltage manufacturing expertise with international quality standards.
10,000+ Units Annual Capacity
Dedicated assembly lines for outdoor circuit breakers, indoor VCBs, and switchgear panels. In-house fabrication of enclosures, busbars, and components ensures quality control.
IEC 62271 Routine Testing on Every Unit
Power-frequency withstand, contact resistance, and mechanical operation tests on every unit before shipment. Equipped with switch characteristic testers, CT/PT testers, and SF6 recycling units.
ISO 9001 / CE / CCC / PCCC Certified
Quality and environmental management systems audited annually. Products carry certifications required for international tenders and customs clearance across 20+ countries.
Spanish INAEL Technology Partner
Licensed SF6 gas-insulated switchgear technology from INAEL (Spain) since 2008, expanding our product line with proven European engineering for ring main units and GIS applications.
30-Day Export Lead Time
Standard 30-day lead time from order confirmation to shipment. Export packing with full inspection reports. Exported to 20+ countries across Europe, Middle East, and Southeast Asia.
Industries We Serve
Our medium voltage switchgear is deployed across diverse industries worldwide — from utility substations and renewable energy farms to data centers and underground mining.
Power Utility & Substation
Primary and secondary distribution switchgear for utility-scale power networks. From 12kV ring main units to 40.5kV metal-enclosed panels.
Renewable Energy (Solar/Wind)
Medium voltage switchgear for solar farm collector substations and wind turbine transformer stations. SF6-free options for sustainability goals.
Industrial & Manufacturing
Motor control centers, power distribution panels, and capacitor switching for factories, steel mills, and petrochemical plants. Up to 5000A/50kA ratings.
Mining & Oil/Gas
Rugged switchgear rated for harsh environments — pollution level IV, seismic intensity 8, operating temperatures from -40 to +70 degrees C. IP67W outdoor protection.
Commercial Buildings & Data Centers
Compact ASN550 switchgear with only 550mm cabinet depth for office buildings, banks, and data centers. Five-point mechanical interlocking for safety.
Infrastructure (Railway/Metro/Airport)
Intelligent switchgear with IEC 61850 / MODBUS communication for rail transit, airports, and port facilities. Gas-insulated options for maritime environments.
Manufacturing Capability
Located in Cixi, Zhejiang — at the heart of China's electrical equipment manufacturing cluster. Our 120-person facility covers the full production cycle from raw material processing to final testing.




Certified for Global Markets
Our quality and environmental management systems are audited annually, and product lines carry the certifications international buyers require for tenders and customs clearance.
Request certificate copiesCompatible Standards
All products are designed, manufactured, and tested in compliance with international and Chinese national standards.
High-voltage switchgear — AC circuit breakers
Metal-enclosed switchgear and controlgear
Switches for rated voltages above 1 kV
Low-voltage switchgear and controlgear assemblies
Communication networks and systems for power utility automation
High-voltage AC circuit breakers (China national standard)
Metal-enclosed switchgear — 3.6-40.5kV (China)
Low-voltage switchgear assemblies (China)
How to Order — 5 Simple Steps
From initial inquiry to shipment in as fast as 30 days. Our process ensures every unit meets your exact specifications.
Submit Inquiry
Share your project requirements — voltage class, current ratings, quantity, and any special specifications. We respond within 24 hours.
Engineering Review
Our technical team reviews your specifications against IEC 62271 standards and prepares a detailed quotation with GA drawings.
Order Confirmation
Upon agreement on pricing and terms, we release production drawings and schedule your order in our production plan.
Manufacturing & Testing
In-house fabrication, assembly, and IEC 62271 routine testing. Every unit undergoes power-frequency withstand and contact resistance tests.
Export Packing & Shipment
Professional export packing with full inspection reports. Standard 30-day lead time. FOB Ningbo or CIF to your port.
Technical Resources
In-depth engineering guides from our technical team to help you select the right switchgear for your application.
VCB vs SF6 Circuit Breaker: 10 Key Differences
What Is a Ring Main Unit (RMU)?
Metal-Clad vs Metal-Enclosed Switchgear
SF6-Free Switchgear: The Future of Medium Voltage
How to Choose a Switchgear Manufacturer
IEC 62271 Standard: Switchgear Guide
Frequently Asked Questions About Our Switchgear
What voltage range does your medium voltage switchgear cover?
Do you offer SF6-free switchgear solutions?
What certifications do your switchgear products have?
What is the MOQ for switchgear orders?
Can you customize switchgear to our specifications?
Ready to Source Medium Voltage Switchgear?
Get factory-direct pricing on vacuum circuit breakers, RMUs, GIS, and switchgear panels. Our engineers respond within 24 hours with a detailed quotation.