Book excerpt: The 2020 Residential Electrician study guide will help you prepare for the exam by providing 12 practice open book exams and 2 Final Closed Book Exams. This book also covers most topics that are included on all Journeyman Electricians exams such as conductor sizing and protection, motors, transformers, voltage drop, over-current protection and residential and commercial load calculations. The text contains the most widely used electrical calculations and formulas the reader needs to pass the Journeyman electrical competency exam.