If you pick up a copy of the NEC and feel its heft, you can understand why many electricians and engineers struggle to find the requirements that apply to their application. But there’s a simple solution to this problem. It’s in how the NEC is arranged.
The NEC consists of nine chapters plus a section of appendices (called “Annexes). You don’t have to read through all nine chapters. The first four chapters apply generally to all installations. As you become more familiar with these chapters and the requirements in them, you’ll know things like “Requirements for services are in Art. 230” and just go to the appropriate chapter. There’s logic to how these chapters are structured, making it easy to scan through the chapter to find what you’re looking for.
The next three chapters supplement or modify the first four, if your application is for special occupancies (Chapter 5), special equipment (Chapter 6), or special conditions (Chapter 7). All of the chapters have meaningful names, so you can peruse the Table of Contents to see if your application might be covered. For example, suppose your application is an elevator. Elevators are a specialized type of equipment, so you look in Chapter 6 and find they’re covered by Art. 620.
