What type of wire should be used for wiring in the distribution cabinet

Copper conductors with appropriate insulation, typically flexible or PR-type, are used for internal wiring in distribution cabinets, following standards like IEC 60204-1, IEC 61439, and UL 508A.Conductor MaterialFor internal wiring in distribution cabinets, copper is the preferred conductor material due to its excellent electrical conductivity and reliability. Aluminum is generally avoided for internal panel wiring because it is less flexible and more prone to connection issues over time, though it may be used in external distribution lines .Insulation TypesThe insulation of wires depends on the application and voltage rating:Flexible cables are commonly used for wiring inside cabinets, switch boxes, and small electrical appliances, allowing easier routing and connection .PR (polyethylene or elastomer) insulated conductors are typically used for cross-sections greater than 35 mm², suitable for higher current circuits .High-security halogen-free (LSZH) cables are recommended in public or emergency circuits to reduce smoke and toxic gas emission in case of fire .Wire Sizing and Current CapacityThe cross-section of the wire must be selected based on the current-carrying requirements of the circuit. Standards such as IEC 60364-5-52 and UL 508A provide guidance:Main current wiring should generally be no smaller than 14 AWG for internal circuits .For motors or heating systems, the conductor must handle at least 125% of the full-load current.Cross-sections are chosen according to calculated current, installation method, and ambient temperature conditions .Color CodingProper color coding ensures safety and easy maintenance:Green/yellow for protective earth (ground)Blue for neutralOther colors (e.g., black for live circuits) may be used according to UL 508A or IEC recommendations .Standards ComplianceWiring in distribution cabinets must comply with international and regional standards to ensure safety and reliability:IEC 60204-1: Safety of electrical equipment in industrial machineryIEC 61439: Low-voltage switchgear and controlgear assembliesUL 508A: Industrial control panels in North AmericaNF C 15-100: Low-voltage electrical installations in France and Quebec SummaryFor wiring inside a distribution cabinet:Use copper conductors with flexible or PR insulation.Select cross-section based on current requirements and standards.Follow color coding for ground, neutral, and live wires.Ensure compliance with IEC, UL, and local standards.Consider LSZH cables for safety in public or emergency circuits. This approach ensures safe, reliable, and maintainable wiring within distribution cabinets.