RN2 High Voltage Fuse

1. Product Overview

RN2 high voltage current-limiting fuse is a key primary protection component for 10kV medium voltage power distribution systems. It is specially designed for voltage transformer overcurrent and short-circuit protection, widely matched with JDZ10, JDZ, JDJ series voltage transformers installed in indoor switchgear, metering cabinets and substation panels.

This fuse adopts quartz sand as arc-extinguishing medium with fine silver wire as melt element. It features excellent current-limiting performance, fast breaking speed and stable arc extinction capacity. When short-circuit or overload fault occurs in the PT circuit, RN2 fuse can quickly cut off fault current to avoid permanent damage to voltage transformers and other secondary measuring instruments.

2. Main Features

• Special protection fuse for 10kV voltage transformers
• Quartz sand filling for reliable arc extinguishing
• Silver alloy melt with precise breaking characteristic
• Outstanding current-limiting performance, low cut-off current
• Fast fault breaking speed, effectively protect PT equipment
• Compact cylindrical structure, easy to install inside switchgear
• Stable performance under 50Hz / 60Hz dual frequency
• Simple structure, low failure rate, convenient replacement
• Fully comply with IEC international standards for overseas power projects

3. Technical Specifications

4. Structure Description

5. Working Principle

Under normal rated operating condition, the silver melt inside RN2 fuse keeps intact, and the circuit conducts normally with tiny power loss.

When short-circuit fault or severe overload happens to the matched voltage transformer, huge fault current passes through the melt. The silver wire melts and vaporizes instantly to generate high-temperature electric arc. The surrounding quartz sand rapidly absorbs arc energy, cools down and quenches the arc within milliseconds, cutting off the fault circuit completely.

After fusing, the circuit is permanently disconnected, which can effectively isolate fault points and prevent PT burnout, insulation breakdown and secondary equipment damage.

6. Application Scope

RN2 high voltage fuse is exclusively applied for voltage transformer protection in the below equipment:

10kV indoor medium voltage switchgear

High voltage metering cabinet

Transformer inlet & outlet cabinet

Busbar PT cabinet

Distribution automation control panel

Industrial plant medium voltage power room

Commercial building MV power supply system

Photovoltaic & energy storage medium voltage station

Municipal power grid reconstruction projects

7. Installation Instructions

1. Check the porcelain tube surface before installation, confirm no cracks, chipping or sealing damage. Verify rated voltage and melt current match design requirements.
2. Install the fuse horizontally or vertically on dedicated fuse holder inside switchgear, keep stable clamping without loose contact.
3. Ensure two end caps fully contact with holder conductive clips to avoid overheating during operation.
4. Reserve enough insulation clearance between fuse and other live metal parts.
5. Do not bend, knock or squeeze the porcelain tube during installation to avoid hidden cracks.
6. After installation, manually shake the fuse slightly to check firm fixation; test circuit continuity before power transmission.
7. Replace with new identical specification fuse once the melt blows out; prohibited to reuse blown fuse.

8. Safety Warnings

1. All installation, replacement and inspection work must be operated by certified professional electrical workers.
2. Cut off all upstream high voltage power, complete power failure, test and grounding operation before replacing fuse.
3. Strictly forbid touching fuse body when the cabinet is energized, to avoid electric shock accident.
4. Do not use non-standard melt or copper wire to replace blown RN2 fuse, which will lose short-circuit protection function and cause serious equipment accident.
5. If porcelain tube cracks, leakage or abnormal overheating occurs during operation, cut off power supply and replace immediately.
6. Collect broken fuses for centralized disposal, prohibit random discard.
7. Keep product specification label and technical data sheet for later reference.

9. Ordering Information

Please offer the following technical parameters when placing orders:

1. Full model: RN2
2. Rated voltage (standard 10kV)
3. Rated melt current
4. Installation way (horizontal / vertical)
5. Order quantity
6. Target market applicable standard (IEC standard as default)

10. Packing & Export Notice

Each RN2 high voltage fuse is independently wrapped with anti-collision bubble film, then packed into thick neutral export cartons. Cartons are reinforced with packing tape to resist collision, vibration and dampness during sea, land and air long-distance transportation. Outer packaging can attach neutral English labels without any brand logo, convenient for overseas customs clearance and warehouse storage.