Indoor distribution box installation pre-embedded

Pre-embedded indoor distribution boxes should be installed flush with the wall, properly leveled, reinforced, and grounded before final wiring and panel assembly.

Preparation and Placement

Before embedding, ensure that the wall and ceiling construction is complete, including plastering and decoration, to avoid damage during installation. The recommended installation height is typically 1. 5 meters from the bottom edge of the box to the floor, and for distribution boards, at least 1.

8 meters. The box should be level and vertical, with a deviation of no more than 3mm, and the edges of the panel should align with the wall surface without protruding or being recessed.

Embedding and Reinforcement

For boxes wider than 500mm, a concrete lintel should be installed above the box; for widths over 300mm, a reinforced brick lintel is recommended to prevent structural pressure on the box. The surrounding space should be filled with cement mortar to secure the box. Anti-corrosion paint should be applied to parts in contact with the wall to prevent rust.

Fixing and Grounding

The box can be fixed using embedded bolts, dovetail bolts, or split bolts depending on wall type. Each box should be grounded separately, connecting the PE bar inside the box to the foundation or grounding system using copper wire with a spring washer for anti-loosening. Cabinet doors should also be connected to the PE row to ensure safety.

Wiring and Safety Checks

Before connecting power, verify that surge protective devices (SPD) and other components meet design specifications, and ensure proper insulation and wire gauge (minimum 2. 5mm² for current circuits, 1. 5mm² for other circuits),.

Secondary circuits should be bundled and labeled, keeping AC, DC, and control lines separate to avoid interference. Conduct visual inspections and multimeter tests before powering on to confirm correct installation and safety.

Final Considerations

After embedding, the box should remain clean and protected until panel installation. Ensure that knock-out holes are opened as needed for wiring, and that the box is flush with the wall. Reinforce the box during initial construction to prevent damage from wall load or subsequent installation of terminal electrical appliances.

Following these steps ensures a safe, compliant, and durable installation.