RN Indoor High Voltage Fuse for 3.6–12kV Switchgear

Compact 3.6–12kV Fuse for Switchgear Transformer and Capacitor Bank Protection

The RN indoor current-limiting fuse is a specialized protective device for medium voltage switchgear systems, used primarily to protect transformers, voltage transformers, and capacitor banks from short-circuit damage. Unlike drop-out types, RN fuses are installed within sealed panels and are designed to interrupt high fault currents with minimal let-through energy.

This makes them ideal for compact indoor substations, metal-clad switchgear (like KYN28-12), and equipment where fast arc interruption is essential to limit downstream damage.

🔧 Key Features

Model: RN (e.g., RN2, RN3, RN6)
Rated Voltage: 3.6kV / 7.2kV / 12kV
Current Rating: 2A – 200A depending on application
Breaking Capacity: Up to 50kA
Installation: Indoor switchgear, busbar compartment, VT panel
Fuse Type: Full-range or back-up type, current-limiting
Standards: IEC 60282-1, GB/T 15166.2

⚙️ Technical Specifications

Parameter	Value
Rated Voltage	3.6 / 7.2 / 12kV
Rated Current	2A – 200A
Breaking Capacity	Up to 50kA
Fuse Type	Full-range / Back-up
Power Frequency Withstand	≥42kV (1 min)
Lightning Impulse Withstand	≥75kV
Time-Current Characteristic	Fast (Class aR / gR)
Dimensions	292mm / 442mm / 537mm (typical)
Mounting Style	DIN plug-in / bolt-in type
Installation Environment	Indoor, ≤2000m altitude

🏢 Application Scenarios

This product is purpose-built for indoor cabinet installations, making it distinctly different from pole-mounted fuses:

✅ Medium Voltage Switchgear (e.g. KYN28, XGN, HXGN)

Installed inside the busbar or VT chamber to disconnect in fault conditions with precision and safety.

✅ Dry-Type or Oil-Immersed Transformers (≤1600kVA)

Used to protect both HV side and instrument transformers in 11kV or 6kV networks.

✅ Capacitor Banks in Power Factor Correction

Prevents catastrophic failure of capacitor units during overcurrent, common in industrial compensation systems.

✅ Voltage Transformer (PT) Protection

Especially for instrument protection in control panels, where let-through energy must be minimal.

RN Indoor High Voltage Fuse for 3.6–12kV Switchgear

🧱 Product Structure Highlights

High-Purity Silver Element: Engineered for rapid melting and minimal arc energy
Silica Quartz Arc Tube: Fills arc chamber to quench instantly, extending panel life
DIN Mounting Ends: Plug-in or bolted types for switchgear compatibility
Sealed Ceramic Body: Explosion-resistant and pressure-balanced
Fuse Link Consistency: Time-current curve precision for coordinated tripping with breakers

✅ Compliance and Certifications

Fully tested per IEC 60282-1, suitable for international switchgear brands
Compatible with ABB, Schneider, Siemens, and China-made cabinets
Factory test report provided with each batch, including routine high-voltage withstand test and resistance test

❓ Frequently Asked Questions

• Is this fuse suitable for outdoor use?
No. The RN series is specifically for indoor switchgear applications only.

• What’s the difference between RN and XRNT types?
RN fuses are generally backup types used in transformer and PT protection; XRNT may include full-range options.

• How do I select the right size?
We provide coordination tables to match fuse size with transformer capacity and breaker rating.

• What happens when the fuse blows?
An indicator pops out, and it can be connected to trip a breaker or trigger an alarm.

• Can it work in ring main units (RMU)?
Yes, if the unit is compatible with indoor DIN fuse dimensions and supports current-limiting protection.