Wiring method for lighting module in distribution box

Lighting module distribution boxes are typically wired using a modular home-run system with integrated bus cables, SPN circuits, and clearly marked conductors for each output port.

Power Input and Home-

Run Cabling

The distribution box receives power from a main distribution board via a single multi-core home-run cable. For a 6-port box, an 18-core cable is used; for a 9-port box, a 27-core cable is typical. Each conductor is marked at 150mm intervals to correspond with its output port, facilitating identification and connection to Light Control Modules (LCMs) or luminaires.

The home-run cable may also include an integral bus cable (shielded or unshielded) for communication with lighting controllers or building management systems.

Circuit Configuration

Distribution boxes can be configured in radial or ring circuits, depending on the installation requirements.

Each SP

N (Single Pole + Neutral) circuit is connected to the corresponding output port. For dual-circuit switching, some systems allow separation of circuits A and B by removing copper links and wiring the switch returns to terminals SW(A) and SW(B),. Load balancing is essential, especially for LED or high-power lighting systems, to prevent voltage drops and ensure even distribution.

Modular Connections

Modern systems, such as the Vitesse Modular or flex7 boxes, use modular connectors for both power and control signals. Starter modules provide 4-pole connections for standard luminaires, while extender modules allow additional outputs. Control inputs and outputs are pluggable, enabling easy expansion or replacement without rewiring the entire system.

Flexible cords from sensors or switches are connected to dedicated terminal blocks, not the main power terminals, to maintain safety and compliance.

Grounding and Mounting

Proper grounding is critical. The distribution box should be mounted on a wall, ceiling, cable tray, or suspended via threaded rods, with the home-run cable armoring securely anchored. Metal brackets often provide both structural support and grounding points.

Ensure all circuits are phase balanced and that the system complies with local electrical codes, such as BS7671 in the UK.

Bus Integration and Control

For systems with integrated bus communication, a separate bus cable runs from the distribution box to the lighting area controller. This allows centralized control, dimming, and automation. Extender cables with integral bus lines connect to LCMs, enabling both power and signal distribution in a single run.

Summary

Use a multi-core home-run cable with marked conductors for each port. Configure circuits as radial or ring, ensuring load balance. Connect flexible cords for sensors to dedicated terminal blocks.

Use modular starter and extender modules for easy expansion. Ensure proper grounding, mounting, and compliance with electrical standards. Integrate bus cables for control and automation where applicable.

Following these methods ensures a safe, modular, and expandable lighting distribution system suitable for modern commercial or residential installations.