Choose the right box based on environment (indoor/outdoor), load capacity, and durability. Check for proper IP/NEMA ratings and material quality. Explore a complete walkthrough of an injection moulding machine, focusing on the internal circuits, switch configurations, and full wiring diagrams. Equipment installation. A distribution box is the heart of any electrical system. The method includes the steps of connecting electrical leads to coded electrical connectors secured to the mold; connecting electrical connectors to detachable electrical cables; and. Proper vertical injection machine installation is essential for production efficiency.