Low voltage distribution box outdoor use requires IP65 or NEMA 4X ratings, corrosion-resistant materials, and proper sealing for lasting weather protection. NEC (National Electrical Code) Article 314 provides strict requirements for these installations, and for good reason. This guide breaks down everything homeowners need to know about outdoor electrical junction boxes in plain English. While the IEC 60364 standard. This article is about Non-Hazardous Outdoor Enclosures, Installation and Commissioning and Materials Selection & Requirements of Electrical Power System as per International Codes and standards for Commercial Buildings, Plants and Refinery Projects. (c) IEC 60529 Type IP 54 or better, manufactured. 4 KV Substation of the ratings indicated above. Ensure safe placement: install in. of Plot & Service junction box with all accessories for trouble free and efficient operation. Applicable Standards: 1200V DC. IS 13703 (Part-1&2)-1993 / IEC 60263/1-1986:.