Ampacity and Wire Sizing

This course is all about a really fundamental and useful concept in electrical work – the ampacity of conductors—that is, the maximum amount of current that a conductor can carry on a continuous basis without getting dangerously hot. In the lessons of this course you will progress gradually, beginning with a simple introduction to the key ampacity tables in the National Electrical Code, because working with ampacity is all about knowing where to find the values. We show you exactly how to find the ampacity for any wire, but then go further to explain things like how to choose which temperature column to use, based on environmental and code exceptions. And we cover, pretty carefully, the reasons why you often have to adjust the values found in the ampacity tables, based on what are called ‘conditions of use’ like the ambient temperature around a wire or how many wires are crammed inside a conduit. And we end the course with a nice set of worked examples, so you really get comfortable with applying everything you have learned about ampacity.