COURSE DESCRIPTION

This course describes methods that can be used to troubleshoot two types of problems that may affect URD systems: transformer faults and cable faults.

COURSE GOALS

• Describe the layout of a typical underground residential distribution system.
• Describe methods that can be used to troubleshoot transformer faults.
• Describe methods that can be used to troubleshoot cable faults.
• Identify equipment used in the troubleshooting process.

SUBJECTS AND OBJECTIVES

Isolating Transformer Faults

• Describe the layout of a typical underground residential distribution (URD) system.
• Describe how to troubleshoot a transformer fault in which only the transformer primary fuse is blown.
• Describe how to troubleshoot a transformer fault in which the rise pole fuse is blown, but the transformer primary fuse is intact.

Isolating Cable Faults – Part 1

• Describe how to troubleshoot a cable fault in a system equipped with cable fault indicators.
• Identify three common types of cable fault indicators.
• Describe how to troubleshoot a cable fault by isolating and testing one section of cable at a time starting at the normally open point in the loop.
• Describe how to troubleshoot a cable fault by isolating and testing one section of cable at a time starting at a blown riser pole fuse.

Isolating Cable Faults – Part 2

• Describe how to troubleshoot a cable fault by re-energizing one section of cable at a time.
• Describe how the area to be isolated and tested for a cable fault in a URD system can be reduced.
• Describe the major difference between troubleshooting a transformer fault or a cable fault in a three-phase system and troubleshooting a transformer fault or a cable fault in a single-phase system.
• Describe how to troubleshoot a cable fault using a radar fault locator.