The metal box of the distribution box, the electrical installation board, and the metal base and casing of the electrical appliances in the box must be grounded. The protective neutral wire should be reliably connected through the terminal board. For cases where the precautions were not followed, some corrective. In this guide, we'll break down everything you need to know to install a distribution box correctly and confidently. Choose the right box based on environment (indoor/outdoor), load capacity, and durability. Ensure safe placement: install in. This technical article covers recommendations for choosing cross-sections of the wiring conductors inside switchboards, their connection methods, various wiring dos, don'ts and precautions in protecting from short-circuit and magnetic effect.