Distribution Line Safety

COURSE DESCRIPTION

This course introduces students to the principles and techniques of single-point, or equipotential grounding. For best results, students should have a basic knowledge of electrical theory, overhead distribution systems and equipment, grounding theory, equipment, and application and common work methods and procedures used in overhead distribution line maintenance.

COURSE GOALS

• Explain the purpose of grounding an overhead line during maintenance work.

• Describe ways in which an isolated or de-energized line can become energized.

• Define the term “zone of equipotential”.

• Explain how equipotential grounding operates to safeguard lineworkers during a ground fault condition.

• Describe how grounding equipment is used to set up a zone for equipotential.

SUBJECTS AND OBJECTIVES

Grounding

• Define the terms “energized,” “isolated,” and “de-energized” with respect to overhead linework.

• Describe ways in which an isolated or de-energized line can become energized.

• Describe a typical procedure used to ground an isolated overhead line.

Equipotential Grounding

• Use Ohm’s law to describe current flow in a de-energized overhead line during a ground fault condition.

• Define the term “zone of equipotential”.

• Describe a method that can be used to establish a zone of equipotential.

Equipotential Grounding Connections

• Describe how grounding equipment can be used to create a zone of equipotential on a three-phase overhead line.