System Protection Technology

The objective of this module is to draw attention to the problem of inadvertent trips and misoperation of protection equipment. Typical case studies are presented, with the conclusions leading to recommended procedures to help reduce inadvertent trips.

After completion of this videotape and the associated workbook, participants will be able to understand the following concepts and apply them in their day-to-day work activities. They will also be able to answer test questions on these subjects:

• Definitions of “Inadvertent Trips” and “Misoperation”
• The main causes of inadvertent trips and misoperation
• Effects of installation errors such as: mistakes in wiring, inaccurate drawings, faulty equipment from the manufacturer, incorrect relay settings
• The necessity for testing new installations
• Typical procedures for commissioning tests
• The effect of protection equipment failure and subsequent misoperation
• The need for routine tests at set periodic intervals
• Precautions required when conducting routine tests
• The need for thorough preparation before commencing routine tests
• Cooperation with the operator, equipment isolation and clearance
• Precautions against interference with live circuits
• Typical procedures for routine testing
• The objective of in-service testing
• The potential for human error and resultant inadvertent trips
• Requirements for active protection during in-service testing
• System limitations on in-service testing
• Preparation and typical procedures for in-service testing
• Responding to trouble calls
• Investigation of protection equipment misoperation
• Incident reports