Automation Lab – 24V DC Contactor Circuits: Starting, Reversing and Star-Delta

Lab Objectives

• Learn how electrical contactors and their command and control circuits work and are used, with specific reference to 24 V DC systems.
• Develop practical skills in assembling, wiring and configuring industrial electrical panels through exercises on real components (contactors, relays, switches, timers, limit switches).
• Build and test control circuits for starting, stopping and reversing three-phase asynchronous motors, including star-delta systems and two-speed operation (Dahlander circuit).
• Analyse and solve real problems, such as choosing protection devices, correctly sizing equipment and the logical sequence of commands.

Educational Aims

• Train skilled technicians for industrial automation, plant maintenance and applied electrical engineering, with a solid theoretical and practical foundation.
• Complement curricular knowledge with a lab-based approach built on real simulations, through guided exercises, review questions and additional assignments.
• Give students the skills needed to read and interpret wiring diagrams, design simple circuits and verify their operation, supported by technical documentation, worksheets, TechnoCards and exercises with dedicated software.
• Develop operational autonomy, problem-solving skills and attention to electrical safety regulations, using A4 training panels with protected connections and accessible configurations.

Conclusion

The Contactor Control II – 24 V DC Control Circuits and Installation lab is a complete, highly vocational training environment designed to prepare students and future technicians for the world of electrical installations and industrial automation. Real industrial components (motors, contactors, timer relays, miniature circuit breakers, limit switches) allow students to apply theory directly, building and testing control circuits for three-phase motors in different operating configurations. Thanks to structured documentation and progressive activities, the lab fosters effective, interactive, competence-based experiential learning. The whole system also promotes a methodological approach in line with the principles of competence-based teaching, encouraging autonomy, safety and collaboration. This lab provides a solid foundation for entering the profession and for further study in technical and technological fields. This solution includes technological systems that promote inclusion and equal opportunities through innovative teaching methods. It is designed to encourage active, collaborative learning.