The JN15-12/31.5 Indoor earthing switch is designed for 3-12kV AC medium-voltage systems operating at 50-60Hz. It provides safe earthing, fault isolation, and high-voltage switchgear protection. Compact, modular design supports industrial, commercial, and utility applications, ensuring personnel safety, equipment reliability, and efficient indoor HV switchgear operation.

Introduction

The JN15-12/31.5 Indoor Earthing Switch is a crucial component for medium-voltage AC Power Systems. Designed for 3-12kV AC and 50-60Hz operations, this high-voltage earthing switch provides reliable earthing, circuit isolation, and protection for indoor switchgear systems. Its modular design and ES1-type improvements make it ideal for industrial plants, commercial facilities, and utility networks.

Earthing Switches like the JN15-12/31.5 play a vital role in power distribution. They ensure safety during maintenance, prevent accidental energization, and protect electrical equipment from fault currents. With its compact and robust design, the switch guarantees reliable performance, operational safety, and long-term durability.

Key Features of JN15-12/31.5 Earthing Switch

1. Rated Voltage: Operates reliably within 3-12kV AC systems.

2. Frequency Compatibility: Supports 50-60Hz operations.

3. Indoor Application: Optimized for installation in switchgear rooms.

4. Improved ES1 Type Design: Provides enhanced mechanical reliability.

5. Modular Structure: Easily integrates into indoor HV switchgear cabinets.

6. Safety Interlocks: Prevents incorrect operation and ensures personnel safety.

7. Three-Phase Earthing: Maintains balanced grounding across circuits.

8. High Mechanical Endurance: Withstands repeated switching operations.

9. Compact Design: Maximizes available switchgear space.

10. Standards Compliance: Meets IEC and GB regulations for medium-voltage switchgear.

Technical Specifications

• Model: JN15-12/31.5

• Rated Voltage: 3-12kV AC

• Rated Current: 630A – 1250A

• Short-Time Withstand Current: 20kA – 31.5kA

• Peak Withstand Current: 40kA

• Rated Short-Circuit Making Current: 31.5kA

• Insulation Level:

• Power Frequency Withstand Voltage: 28kV

• Lightning Impulse Withstand Voltage: 75kV

• Mechanical Endurance: ≥2000 operations

• Ambient Temperature: -5°C to +40°C

• Installation: Indoor modular switchgear integration

Functions and Applications

1. Reliable Earthing

The JN15-12/31.5 provides a secure earthing path for medium-voltage circuits, ensuring safety during maintenance or inspection. Residual currents are safely discharged, reducing the risk of accidental energization and protecting personnel.

2. Fault Isolation

It allows safe isolation of circuits to prevent damage to transformers, circuit breakers, and other high-voltage equipment. Effective isolation enhances system stability and reduces downtime during fault events.

3. Modular Switchgear Integration

The switch’s compact design enables seamless installation within indoor switchgear cabinets. Its modularity allows for easy upgrades, maintenance, and expansion without system disruption.

4. Safety Interlocks

Mechanical and electrical interlocks ensure that the switch cannot operate when circuits are live, enhancing operator safety and preventing damage to equipment.

5. Industrial and Commercial Use

• Medium-voltage distribution in manufacturing plants and refineries.

• Power distribution substations for utility networks.

• Commercial complexes, data centers, and hospitals.

• Renewable energy plants, including solar and wind farms.

• Transportation and rail infrastructure requiring medium-voltage earthing.

Design Advantages

• Compact Indoor Design: Optimizes switchgear room layout.

• Enhanced Safety Features: Prevents operator errors.

• High Insulation Reliability: Withstands voltage stress and ensures stable operation.

• Modular Flexibility: Supports system expansion and retrofitting.

• Durable Mechanical Components: Built to endure thousands of operations.

Installation Guidelines

1. Site Assessment: Check switchgear room conditions, including temperature, humidity, and dust levels.

2. Mechanical Assembly: Securely install the earthing switch in the modular switchgear frame.

3. Interlock Verification: Align mechanical and electrical interlocks correctly.

4. Pre-Energization Testing: Measure continuity, insulation resistance, and mechanical operation.

5. Commissioning: Follow IEC or local standards for final system commissioning.

Maintenance Recommendations

• Inspect mechanical and electrical components regularly.

• Lubricate moving parts and tighten connections to prevent corrosion.

• Test insulation resistance periodically.

• Check interlock functionality to ensure operational safety.

• Schedule preventive maintenance to reduce unplanned downtime.

Advantages of Using JN15-12/31.5 Earthing Switch

1. Operational Safety: Protects personnel during maintenance.

2. Equipment Protection: Prevents damage during fault currents or overloads.

3. Reliable Performance: Stable operation under medium-voltage AC conditions.

4. Space Efficiency: Compact design fits modular indoor switchgear.

5. Standards Compliance: IEC and GB regulations ensure quality and safety.

6. Long-Term Savings: Reduced maintenance and downtime.

7. Flexible Integration: Supports retrofits and new installations.

Compliance and Standards

• IEC 62271-102 – AC disconnectors and earthing switches

• IEC 62271-200 – Medium-voltage metal-enclosed switchgear

• GB/T 3906-2006 – High-voltage switchgear and controlgear

• ISO 9001 – Quality management certification

Integration with Indoor Switchgear

• Ensures safe maintenance operations.

• Provides three-phase earthing for balanced protection.

• Guards against short-circuit and overload scenarios.

• Compatible with monitoring devices for real-time diagnostics.

• Simplifies maintenance and replacement without power disruption.

Future Applications

The JN15-12/31.5 Indoor Earthing Switch is suitable for modern smart grids and renewable energy systems:

• Intelligent Monitoring: Predictive maintenance and real-time diagnostics.

• SCADA Integration: Remote control and supervision of medium-voltage circuits.

• Smart Grid Support: Efficient energy distribution and fault isolation.

• Eco-Friendly Operation: Low energy loss and minimal environmental impact.

Conclusion

The JN15-12/31.5 Indoor high voltage earthing switch is a reliable, safe, and modular solution for 3-12kV AC medium-voltage systems. Its improved ES1 design, safety interlocks, and long mechanical endurance make it ideal for industrial, commercial, and utility applications.

By integrating the JN15-12/31.5, operators ensure personnel safety, equipment protection, and efficient system maintenance. Its modular indoor switchgear compatibility supports easy installation, future upgrades, and dependable medium-voltage power distribution.