4 CEU Hours – 20170417 Class 2 and Class 3 Circuits NEC 725 , a 4 hour CEU NEC code class. This class includes the changes and the additions to the code for 2017. Including the changes as they relate to PoE and other power and listing changes. Other topics include control and signal circuits, Circuit identification and installation requirements. 4 NEC code Hours. This class meets the State requirement for 4 Code hours.