Distribution boxes AL and LB

AL and LB distribution boxes are types of electrical enclosures used to safely distribute power, with LB typically referring to power distribution blocks and AL to equipment or derivation boxes.

Type LB Distribution Boxes

Type LB distribution boxes are commonly associated with power distribution blocks used inside control panels. These blocks allow power from a single source to be distributed to multiple loads efficiently and safely. They are UL Listed for code compliance and are suitable for various industrial and commercial applications. LB blocks are designed for flexible installation, often featuring modular components and accessories to match specific electrical layouts, and are ideal for centralized power distribution within panels (Schneider Electric) .

Type AL Distribution Boxes

Type AL boxes, often referred to as equipment or derivation boxes, are used for branching circuits, control gear, and spot lighting in indoor electrical installations. They are typically made from polystyrene (RAL 9003) with galvanised steel screws and comply with EN 60670-1 standards. AL boxes provide IP20 to IP40 protection depending on the model and installation, and are suitable for mounting on solid, non-combustible walls. They are designed for easy assembly and maintenance, with detachable openings for wiring and integration into larger electrical systems (AL-SA) .

Key Differences

• Function: LB boxes focus on power distribution within control panels, while AL boxes are used for branching and housing control gear in building installations.
• Construction: LB blocks are modular and designed for high-current connections, whereas AL boxes are lightweight, often plastic, and intended for low to medium voltage indoor circuits.
• Standards and Protection: LB blocks are UL Listed and suitable for industrial environments, while AL boxes comply with EN standards and provide IP20–IP40 protection for indoor use.

Applications

• LB: Industrial control panels, machinery power distribution, centralized electrical systems.
• AL: Indoor lighting circuits, small control systems, junctions for residential or commercial wiring.

Summary

Both AL and LB distribution boxes are essential for safe and organized electrical distribution, but they serve different roles: LB for centralized power distribution and AL for branching and control applications. Choosing the correct type depends on the current rating, installation environment, and specific electrical requirements of the project .