An XL-type secondary distribution box is a modular, low-voltage power distribution unit designed for safe, efficient, and flexible electrical distribution in industrial, commercial, and large building applications.

Overview

The XL-type distribution box is a low-voltage switchgear and control device suitable for AC 50Hz systems with rated voltages up to 500V. It is widely used in power plants, substations, large buildings, and industrial facilities for power control, distribution, and protection purposes ( ). The XL-21 model is a common indoor variant, installed against walls with front access for maintenance ( ).

Key Features

• Modular and Compact Design: The box uses a steel plate shell with a closed, dustproof structure, allowing flexible wiring and easy maintenance ( ).
• Protection and Safety: Equipped with air circuit breakers, fuses, and optional overvoltage, undervoltage, and phase-loss alarms. The front door can include meters, indicator lights, and operation buttons ( ).
• Voltage and Current Ratings: Rated for 400V AC or 690V AC, with customizable current ratings from 100A to 1600A ( ).
• Environmental Suitability: Designed for ambient temperatures between -5°C and +40°C, altitudes up to 2000 meters, and relative humidity up to 50% at 40°C, with higher humidity allowed at lower temperatures ( ).
• Maintenance-Friendly: Front-access doors expose internal components for inspection and servicing. Components are compact and arranged for flexible wiring ( ).

Applications

XL-type distribution boxes are suitable for:

• Motor control and soft start systems
• Power automatic compensation and generator parallel control
• Electromagnetic DC distribution and step-down start control
• Floor fan and terminal power distribution in industrial and commercial buildings ( )

Installation and Customization

• Indoor/Outdoor Use: IP54 for indoor, IP65 for outdoor environments ( ).
• Flexible Configuration: Modular structure allows adjustment of installation plates, side beams, and cable inlets/outlets according to site requirements ( ).
• Safety Compliance: Conforms to IEC439-1 and GB7251-1997 standards for low-voltage switchgear ( ).

Advantages

• High safety and stability
• Easy maintenance and flexible wiring
• Compact and modular design for space efficiency
• Suitable for harsh or dusty environments
• Scalable for future load expansion ( ) In summary, the XL-type secondary distribution box is a versatile, reliable, and safe solution for low-voltage power distribution, offering modularity, protection, and adaptability for a wide range of industrial and commercial applications.