Introduction to Electrical Systems

Most people start electrical work knowing what electricity does. This course teaches you what it is and how it behaves. You will learn the physics that govern every circuit you will ever work on — voltage, current, resistance, and power — then trace electricity's path from the utility transformer through the service entrance, into the panel, and out to every outlet and fixture in a building. By the time you finish Unit 2, you will understand what every piece of equipment in that chain does, and what breaks when one of them fails. The second half of the course covers the two things that separate a competent electrician from a dangerous one: safety and drawings. Unit 3 does not treat electrical safety as a list of rules to memorize. It explains how electrical injuries actually happen — at 120V, not just high voltage — and what the procedures, equipment, and phenomena like arc flash really mean in practice. Unit 4 then teaches you to read electrical drawings, because every job starts with a set of plans. Symbols, single-line diagrams, wiring diagrams, panel schedules — you will be able to pick up a drawing and know what you are looking at. This course is built for people entering the electrical trade, apprentices in their first years, and anyone who works around electrical systems and needs a solid technical foundation. It does not assume prior knowledge. It does assume you want to understand the work, not just follow steps.