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Motors, Controls, and Troubleshooting

Learn how electric motors work, how to protect and control them, and how to diagnose what went wrong when they don't — the skills that separate a technician who can troubleshoot from one who can only replace parts.

Updated Sep 14, 2026

About this course

Most electricians can wire a motor. Fewer can look at a tripped overload, a motor that hums but won't start, or a VFD fault code and know exactly where to begin. This course is built around that gap. You'll start with how motors actually work — the physics, the nameplate, the difference between single-phase and three-phase — because protection and troubleshooting decisions only make sense once you understand what you're protecting and why it behaves the way it does. From there, the course moves into the two layers of every motor installation: the power circuit and the control circuit. On the power side, you'll learn how NEC Article 430 governs sizing and protection, how starters work, and when a VFD is the right tool instead of across-the-line starting. On the control side, you'll learn to read ladder diagrams, trace seal-in circuits, and follow safety interlocks through a schematic — the skills that let you work through a problem logically instead of swapping parts until something changes. The final unit puts it all together. You'll work through a systematic troubleshooting method, learn the most common motor failure modes and what causes them, and practice reading symptoms the way a good technician does: as clues that point to a cause, not just a component to replace. By the end, you'll have both the conceptual framework and the hands-on diagnostic thinking to handle motor and control problems with confidence.

Details

Updated Sep 14, 2026
4 units, 16 lessons
4 assessments

Skills you'll learn

Motor Selection and Nameplate Reading

Interpret motor nameplate data to select the right motor and enclosure type for a given application and environment.

NEC Article 430 Compliance

Size motor branch-circuit conductors, overcurrent protection, and overload devices in accordance with NEC Article 430 requirements.

Control Circuit Interpretation

Read and trace ladder diagrams, including seal-in circuits and safety interlocks, to understand how a control circuit is supposed to behave before touching any hardware.

VFD and Starter Application

Identify when to use across-the-line starting, reduced-voltage starting, or a variable frequency drive based on load requirements and system constraints.

Systematic Motor Troubleshooting

Apply a structured diagnostic method using a multimeter and symptom-based reasoning to trace motor and control circuit faults to their root cause.

Syllabus

4 units • 16 lessons • 4 assessments

Learning activities

Every lesson gives you several ways to learn.

Read
Flashcards
Quiz
Visual lecture
Podcast
Chat
Arcade
Comic

Frequently asked questions

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