Wiring of the Chinese side distribution box

Proper wiring of a Chinese distribution box involves correct wire sizing, terminal connections, labeling, and organized routing to ensure safety and efficiency.Wire Selection and Sizing

• Main circuit wires should follow the cross-section specified in the wiring diagram, while control circuit wires are typically 1mm², and multi-core cables are 0.3mm² .
• For wires 4mm² and above, use black RV type; for wires below 4mm², use white RV type, with black cable sheaths preferred .
• Always strip insulation using proper tools to avoid damaging the core, and ensure the stripped length allows full insertion into terminal sleeves with 1–2mm extra for secure crimping .

Terminal Connections

• All copper wires must pass through the terminal sleeve; for 0.5mm² wires, fold through the sleeve .
• Avoid using butt connections; if necessary, use soldering with heat-shrink tube protection .
• Ensure tight and secure connections, especially for thick wires like 16mm², as loose lugs can cause arcing due to thermal cycling .

Layout and Routing

• Label all wire heads clearly to identify circuits and avoid confusion during maintenance .
• Route wires to the neutral bar, sub-switches, and ground bar following horizontal and vertical alignment principles .
• Choose the shortest path for connections, keeping PLC input circuits separate from main circuits and other voltage-level control lines .

Component Considerations

• Use appropriate cable glands (M25 or M32 for thick cables) to prevent stress on terminals .
• For compact installations, consider 1P+N RCBOs to save DIN rail space while providing full leakage protection .
• Ensure proper grounding, especially in rural TT systems, by connecting a local earth electrode to the PE busbar .

Safety and Best Practices

• Always turn off the power supply before wiring or maintenance .
• Follow the wiring diagram carefully to understand the flow from the main breaker through circuit breakers, neutral, and ground bars .
• Maintain neat and organized wiring to facilitate troubleshooting and future modifications . By adhering to these guidelines, a Chinese-style distribution box can be wired safely, efficiently, and in compliance with standard practices, ensuring reliable operation and ease of maintenance.