html{display:none} PROT 403: Distribution System Protection | Schweitzer Engineering Laboratories

PROT 403: Distribution System Protection

Unable to retrieve course information.  Please try again later.

Course Base Fees:


Engineers who need a comprehensive understanding of the challenges and solutions for protecting medium-voltage, utility-type distribution systems should attend this course.

PROT 403 provides an overview of the principles, schemes, and devices for protecting medium-voltage distribution feeders and buses. The course provides basic guidelines for overcurrent device coordination in radial systems. It also covers the application of negative-sequence overcurrent and directional overcurrent protection in distribution systems. The course discusses the effect of load and distributed generation sources on protection. It also provides guidelines for fast service restoration in distribution systems.


Day 1
  • Power System Faults
  • Introduction to Distribution Systems
  • Relaying Fundamentals
  • Distribution System Protective Devices
  • Instrument Transformers
Day 2
  • Line Overcurrent Protection: Part 1
  • Class Exercise: Line Overcurrent Protection
  • Line Overcurrent Protection: Part 2
  • Negative-Sequence Overcurrent Protection
  • Line Directional Overcurrent, Distance, and Pilot Protection
Day 3
  • Transformer and Bus Protection
  • Class Exercise: Transformer Differential Protection
  • Class Exercise: Transformer Overcurrent Protection
  • Effect of Load Current
  • Power Quality and Distribution Protection

Day 4

  • Distributed Generation Considerations
  • Class Exercise: Distribution System Protection Coordination

Note: This course teaches fundamental knowledge but does not provide hands-on experience with SEL relays. Day 4 is only half a day.

Course Objectives

At the conclusion of this course, students can:

  • Identify the challenges and solutions to medium-voltage distribution system protection problems
  • Describe distribution system protective devices
  • Select and calculate settings for distribution system protective devices
  • Identify and apply negative-sequence overcurrent protection in distribution systems
  • Explain the effect of load on distribution system protection
  • Identify, apply, and calculate settings for distribution bus protection schemes
  • Describe methods for fast service restoration in distribution systems
  • Identify protection practices and regulations of distribution systems with distributed generation

Request onsite training for your company.

Get Quote

SEL University Training Question



Course Requirements


A degree in electrical engineering or equivalent experience is required. In addition, PROT 403 requires completion of PROT 401: Protecting Power Systems for Engineers or the following:

  • A basic knowledge of power systems and power system protection
  • Familiarity with medium-voltage distribution systems
  • A working knowledge of ac three-phase electrical circuits, trigonometry, basic calculus, complex numbers, and phasor concepts

Recommended reading: We recommend any power system analysis book of your choosing that covers per-unit quantities, symmetrical components, and fault analysis

Course Preparation

Please check the General Course Information page for what you should bring to class.