Check for proper IP/NEMA ratings and material quality. Ensure safe placement: install in dry, accessible areas with good ventilation and at appropriate height (typically ~1. Note Electrical Box and Conduit. 9 This will be the final instalment of Mex-electrical posts, as I think I have covered most of the unique installations that you find in Mexico, and any 3 rd world countries around the world. However, as I posted in a blog entry from January 2011, it's not just the 3 rd world countries that can fall. Learn how to wire a distribution box step by step! This video shows real on-site footage of electrical installation, demonstrating safe and standardized wiring methods used by professionals. It takes the incoming power and safely distributes it to different circuits throughout your building. Whether in a home or an industrial facility, this box keeps. Properly sized THW copper wire "as needed by demand" and "in accordance to sizing tables" for three phase 240V service. There is no real enforced implementation of this "Norma Oficial Mexicana", neither any inspection at service connection anywhere throughout the nation which makes it more of a. plug and socket serving only the boiler and system controls. A pictorial wiring diagram is shown in Frame 40.