FLN36-40.5D SF6 Load Break Switch-Indoor Solution for Safe 36/40.5kV Distribution
FLN36-40.5D SF6 Load Break Switch – Indoor Solution for Safe 36/40.5kV Distribution is an indoor high-voltage load switch designed for 36/40.5kV medium-voltage power distribution systems. It provides reliable load switching, circuit isolation, and grounding functions in a compact SF6-insulated structure.
The FLN36-40.5D can be configured as a standalone load switch or combined with fuses for enhanced short-circuit protection. With reliable interlocking, flexible manual or electric operation, and low-maintenance performance, it is suitable for RMUs, prefabricated substations, industrial facilities, transformer protection, and terminal power distribution systems requiring safe and dependable switching.
Get a QuoteOverview
The FLN36-40.5D Indoor High-Voltage SF6 Load Switch is designed for 36/40.5kV medium-voltage power systems, providing reliable switching and control for indoor power distribution applications. It can be used as a standalone load switch for controlling normal load currents or configured as a load switch-fuse combination to provide additional short-circuit protection.
Featuring SF6 insulation and arc-extinguishing technology, the FLN36-40.5D offers reliable switching performance, compact construction, and stable electrical insulation. Its flexible configuration makes it suitable for indoor switchgear, substations, industrial power distribution systems, and other high-voltage applications requiring dependable load switching and protection.
Operating Conditions
1. Altitude: ≤ 1000 meters;
2. Ambient Temperature: -25°C to +40°C (daily average ≤25°C);
3. Relative Humidity: Daily average ≤95%; Monthly average ≤90%;
4. Vibration Resistance: No frequent violent vibration.
Technical Data
| Item | Unit | Parameter | ||
| Standalone Load Switch (FLN36-40.5D/T630-16) | Load Switch-Fuse Combination (FLN36-40.5D/125-31.5) | |||
| Rated Voltage | kV | 36 / 40.5 | ||
| Rated Frequency | Hz | 50 / 60 | ||
| Rated Current | A | 630 | 125 | |
| Power Frequency Withstand Voltage | kV | 95 / 110 | ||
| Lightning Impulse Withstand Voltage | 185 / 215 | |||
| Rated Short-Circuit Making Current (Peak) | kA | 50 | 50 (Fuse-dependent) | |
| Rated Closed-Loop Breaking Current | A | 630 | 125 | |
| Rated Active Load Breaking Current | 630 | 125 | ||
| Rated Transfer Current | 1000 | / | ||
| Rated Short-Time Withstand Current | kA | 20 | ||
| Rated Cable Charging Breaking Current | A | 50 / 10 | ||
| Cable Charging Breaking Current (Ground Fault) | 20 | |||
| Rated Short-Time Withstand Current (Peak) | kA | 50 | ||
| Short-Time Withstand Current Duration | s | 2 | ||
| Mechanical Life | Times | 2000 | ||
| Rated Transformer Capacity | kVA | ≥5000 | ||
| Rated SF6 Gas Pressure | MPa | 1.5 | ||
| Annual Gas Leakage Rate | % | ≤0.2 | ||
Overall and mounting dimensions(mm)
Key Application Notes
The FLN36-40.5D can be configured as either a standalone SF₆ load switch or a load switch-fuse combination to meet different 36/40.5kV power distribution requirements.
- Standalone Load Switch – FLN36-40.5D/T630-16
Designed for switching load currents, closed-loop currents, no-load transformer currents, and cable charging currents. It is suitable for RMUs, prefabricated substations, and industrial power distribution systems. - Load Switch-Fuse Combination – FLN36-40.5D/125-31.5
Combines load switching with fuse-based short-circuit protection, making it suitable for transformer protection and terminal power supply applications.
Product Features
- Integrated Switching, Isolation, and Grounding
Combines load switching, circuit isolation, and grounding functions within a sealed SF₆-insulated enclosure. - Reliable Safety Interlocking
Incorporates mechanical interlocking to help prevent incorrect operation, together with a safety diaphragm designed to provide pressure relief. - Stable, Low-Maintenance Operation
The sealed SF₆ insulation system provides reliable dielectric performance and helps reduce routine maintenance requirements. - Flexible Operating Configurations
Available with manual or electric operation, with optional accessories including a shunt trip coil, overcurrent release, auxiliary switch, and pressure gauge. - Versatile Power Distribution Applications
Suitable for industrial, commercial, and other medium-voltage power distribution systems requiring reliable load switching and protection.
Maintenance Guidelines
For reliable long-term operation of the FLN36-40.5D, recommended maintenance practices include:
- Regular Mechanical and Electrical Inspection
Inspect the operating mechanism and electrical components periodically, with annual inspection recommended. - SF6 Pressure Monitoring
Check the SF6 gas pressure according to the manufacturer’s specified operating range and investigate any abnormal pressure reduction. - Contact and Mechanism Inspection
Check contacts, springs, operating components, and seals for signs of wear or damage and replace components when necessary. - Enclosure and Sealing Inspection
Ensure the sealed enclosure remains intact and check for visible damage or indications of gas leakage. - Correct Operating Procedures
Follow the specified operating sequence and safety procedures to prevent incorrect switching and ensure safe equipment operation.
