Circuit Breakers Operation and Maintenance

INTRODUCTION Circuit breakers play an important role in the safe distribution of electrical power. The equipment needs to be operated, maintained and installed in a safe manner securing continuity of supply to consumers. This following are important aspects of the circuit breakers:

• Electric power systems are designed to be as fault free as possible through appropriate network design, equipment design, proper installation and on-going maintenance.
• The Circuit breaker and its associated fault detection equipment, protective relaying, is an extremely important device, through its role of clearing short-circuit currents, disconnecting faulty elements from the power network, and thus maintaining the overall integrity of the power network
• If faults are not controlled they can cause unnecessary loss of electricity service with all of its many ramifications.
• The circuit breaker selection and arc extinction methods are of great importance
• Minimising downtime by proper and systematic maintenance program

OBJECTIVES Delegates will gain a detailed appreciation of the following:

• The importance of preventive maintenance check and servicing of the various types of circuit breakers
• Implementation of safe systems of work and operations
• Co-ordination of maintenance activities and maintaining system safety
• To be able to understand the component functionalities of the gas and vacuum circuit breakers
• Methods of arc extinction for MV HV circuit breakers
• Routine inspections and the functions of the micro processor component in the circuit breakers

MATERI 1. Introduction-reasons for faults-and classification of faults

• Distinction between load and fault current
• Sources of short-circuit current
• Introduction to fault calculations
• Balanced and unbalanced faults
• Overview of Power System Protection
  • Measurement-voltage and current transformers
  • Protective device characteristics
  • Types of protection systems
  • The role and importance of the circuit breaker in power systems

2. General principles of arc extinction

• Overview of types of circuit breaker
  • Air-Break
  • Vacuum
  • Gas
  • Other related switching devices
  • The single-line diagram
  • Substation layouts
• Air-break
  • Principles of arc extinction
  • C. circuit breaking
  • C. circuit breaking
  • Contacts and arc initiation
  • Arc chutes
  • Performance characteristics
  • General construction Principles

3. Vacuum

• History-The early years
• The vacuum arc-An overview
• Current interruption in vacuum
• Methods of keeping the arc diffuse
• Current chopping-general implications
• Vacuum interrupters in series
• Design of vacuum switchgear
• Maintenance and testing requirement

4. SF6 Gas

• Properties of SF6
• Principles of arc extinction
• Features of construction
• Mechanism principles
• Insulation principles
• Gas leak problems
• Specific supervision requirements
• Circuit power factor considerations
• Maintenance and testing requirements

5. International Standards

• Importance and relevance to specifications
• ANSI and IEEE
• IEC and IEE
• Circuit breakers and power system
  • Circuit breaker failure and the effects on power system operation
  • Circuit breaker inspection, testing and maintenance program
  • The Principles of modern substation control systems
  • Power circuit breaker maintenance

6. Exercises and Case Studies PARTICIPANT

• Electrical Professionals
• HSE personnel
• Technicians and Supervisors
• Professionals responsible for the operation and maintenance of distribution equipment, who will benefit from sharing experiences in the planning, organisation, and implementation of maintenance activities.

TRAINING METHOD Presentation Discussion Case Study Evaluation FACILITIES Training Kit Handout Certificate Lunch + 2x Coffee Break Souvenir Pick Up Participants (Yogyakarta)