“Code Corner” in HP159 and HP161 detailed the requirements for circuit sizing and overcurrent protection under the 2014 National Electrical Code (NEC). Here are some example calculations to bring that Code language to life. For those who use the 2011 NEC, don’t worry—the calculations are the same.
If you’re rusty on the “whys” behind the calculations, consider reviewing those previous “Code Corner” articles to understand the background information. The calculation examples use: