The most trusted guide to the National Electric Code--fully updated for 2020 rules and regulations Completely revised to align with the 2020 NEC, McGraw-Hill's National Electrical Code (NEC) 2020 Handbook, 30th Edition, offers up-to-date explanations, advice, and analysis for every provision. In-depth coverage of the background and rationale for specific rules enhances understanding of both meaning and application. This practical...