Electrical: Circuit protection
1 AIA CES APPROVED LU AVAILABLE FOR ATTENDEES UPON SUCCESSFUL COMPLETION OF AN EXAM.
The electrical engineer is responsible for designing power distribution systems for buildings. Understanding the full circuit–protection requirements will enable the engineer to design the safest and most reliable electrical distribution systems for buildings.
Circuit protection requires an understanding of the power distribution system as well as the development of a protection scheme for circuit overloads, ground faults, and short circuits. Circuit protection can be further enhanced by implementing selective coordination design techniques.
The design must also provide adequate personnel protection and minimizing disruption.
Unfortunately, there is not a clear, concise “recipe” to follow for such designs. Rather, it requires constant study of the ever–changing codes and standards that can be interpreted in various ways, and then properly applying them into an actionable design.
- Understand the different types of overcurrent protective device strategies to apply in building electrical systems.
- Recognize the difference between ground-fault protection for equipment (GFPE) versus ground-fault circuit interrupters (GFCI; protection for personnel).
- Review how to protect against the various types of faults.
- Understand the role of selective coordination.
- Learn best practices for design via case studies and project examples.
Randall Ehret, PE, Technical Director, Electrical, Environmental Systems Design (ESD) Inc.
John Yoon, PE, LEED AP, Lead Electrical Engineer, McGuire Engineers Inc.