There are clear standards for the colors of power cables for LED displays, as detailed below:
1. International Standard (IEC Standard)
Live Wire (L)
Color: Brown (European/international), Red (US/selective).
Function: The main power supply for the circuit, providing voltage to activate the LEDs.
Example: In an LED display, the live wire connects to the L (Live) terminal of the power outlet, controlling the power input via a switch.
Neutral Wire (N)
Color: Light blue (international), Blue (selective).
Function: The circuit loop, returning current to the power source to ensure voltage stability.
Example: The neutral wire connects to the N (Neutral) terminal of the power outlet, completing a complete circuit with the live wire.
Ground Wire (E)
Color: Yellow and green (global standard).
Function: A safety wire, preventing electric shock from leakage or circuit malfunctions.
Example: The metal casing of an LED display must be grounded to ensure safe operation.
2. Domestic Standards (GB/T Standards)
380V AC Three-Phase Five-Wire System
L1 Phase (A): Yellow
L2 Phase (B): Green
L3 Phase (C): Red
Neutral Wire (N): Light Blue
Earth Wire (PE): Yellow-Green
Application Scenario: Three-phase power supply systems for large LED displays or industrial equipment.
220V AC Single-Phase Three-Wire System
Live Wire (L): Brown-Red
Neutral Wire (N): Light Blue
Earth Wire (PE): Yellow-Green
Application Scenario: Single-phase power supply systems for household or small LED displays.
3. Additional Notes for Special Scenarios
DC Circuit
Positive Wire: Brown
Negative Wire: Blue
Grounded Neutral Wire: Light Blue
Application Scenario: Some LED displays use DC power (such as low-voltage driver modules).
Cable Cross-Section Matches Load
The cable cross-section should be selected based on the load size (e.g., 1.5mm², 2.5mm², 4mm², etc.) to ensure power supply stability. Example: High-power LED displays require cables with a larger cross-sectional area (e.g., 6mm² or larger) to reduce resistance and heat generation.
4. Standard Basis and Importance
Safety Specifications
Comply with the requirements of GB 50303-2015, "Code for Acceptance of Construction Quality of Building Electrical Engineering," to ensure personal and equipment safety.
The ground resistance value must be ≤4Ω to verify grounding effectiveness.
Engineering Practice
In-display wiring must be protected by metal cable ducts or conduits to prevent mechanical damage.
The power plug and socket must be securely fastened to prevent contact problems caused by pulling.
Summary
LED display power cable colors must strictly comply with international (IEC) and domestic (GB) standards. The live, neutral, and ground wires must not be confused. Three-phase power systems must distinguish between phases A/B/C, while single-phase systems must clearly color-code the live and neutral wires. Proper wiring ensures safe operation and prevents the risk of short circuits or electric shock.