Requirements for secondary distribution boxes during rainy weather operations
In order to ensure the waterproof performance of distribution boxes, manufacturers will strictly seal the joints of the box. Usually, rubber sealing rings or sealants are used for sealing to effectively prevent the intrusion of rainwater, sand and dust. Key design points include high-quality materials like ABS plastic, aluminum, and stainless steel that resist corrosion and UV. 2 requires outdoor distribution boxes to have rain-tight enclosures when installed in wet locations, but many installers mistakenly specify NEMA 3 (weather-resistant) instead of NEMA 3R or 4 (rain-tight), leading to inspection failures and costly retrofits. 1 This document is one of a suite of documents intended for designing and installing substations for adoption, and/or for use, by Scottish and Southern Electricity Networks (SSEN) Designers and Installers, covering the following situations.
Read More