After study of this tape and the associated workbook, the participant should be able to understand the following overall concepts and apply them to his day-to-day work activities.

• Why protection is necessary
• The philosophy and objectives of protection
• Zones of protection – local and backup
• Causes and consequences of faults
• Tolerable and intolerable fault conditions
• Relay and circuit breaker combinations
• Elementary tripping circuit
• IEEE Standard device numbers
• Control circuit schematics
• Monitoring relay performance
• Factors affecting relay application
• The need for coordination

After study of this module, the participants should be able to understand the following overall concepts and apply them to their day-to-day work activities. They will also be able to answer related test questions on these subjects:

• Components of the differential relay
• Where differential protection is applied
• The differential principle – bus protection
• Transformer differential protection
• Restraint and harmonic restraint
• Components of the overcurrent relay
• Instantaneous overcurrent protection
• Time-overcurrent protection
• Adjustment of pick-up and time dial
• Construction of directional relays
• The need for directional elements
• Operation of directional relays
• The induction cylinder relay
• Operation of distance relays – balanced beam and MHO type
• Circle diagrams
• Effect of load impedance
• Three-zone elements; back-up protection

After study of this tape and the associated workbook, the participant should be able to understand the following overall concepts and apply them to his day-to-day work activities. He will also be able to answer test questions on the following subjects:

• Function of current and voltage transformers
• Effect of burden and saturation
• CT performance ratings
• VT connections
• The coupling capacitor VT
• Polarity, polarity test
• Three phase circuit diagrams
• Directional sensing for ground faults
• Phasor diagrams, construction and interpretation
• Phase rotation – sequence
• Per unit calculations
• Base voltage and base MVA
• OHMIC impedance and per unit impedance
• MVA fault capacity

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

• Effect of load impedance on current flow
• Effect of short circuit impedance on fault current
• Voltage drop through the system under fault conditions
• Impedance phase angle
• Safety grounding: the ground mat
• Neutral grounding: generator or transformer
• Delta system grounding transformer
• Aerial ground wires on transmission lines
• Limitation of ground fault current through impedance grounding
• Ungrounded systems – Hazards & ground fault detection
• Phasor diagrams for different types of faults
• Resonance
• Ferroresonance
• Distortion of balanced conditions under the various types of faults
• Transposition of balanced conditions at generator to unbalanced conditions at the fault
• Production of positive, negative, and zero sequence components
• Effect of negative and zero sequence components
• Zero and negative sequence relays
• Rules for study of symmetrical components

After studying this tape and the associated workbook, the participant should be able to understand the following overall concepts and apply them to his day-to-day work activities. He will also be able to answer related test questions on these subjects:

• Types of prime movers
• Generator terminal connections
• Generator bus connections
• Unit and station service transformers
• Generator mechanical problems
• General electrical faults
• Generator and prime mover tripping arrangements
• Phase fault primary protection
• Ground fault primary protection
• Backup protection
• Negative phase sequence protection
• Generator capability curve
• Loss of field protection
• Effect of system disturbances
• Generator off-line protection

After study of this tape and the associated workbook, participants should be able to understand the following overall concepts and apply them to their day-to-day work activities. They will also be able to answer related test questions on these subjects.

• Transformer features
• Types of faults
• Overcurrent protection
• Backup coordination
• Primary fuses
• Differential protection
• In-rush current: harmonic filter
• Phasing of differential CTs
• Selecting CT taps
• Calculation of mismatch
• Differential protection for multi-winding transformers
• Connection of multiple restraint coils
• Limitations due to parallel CTs
• Single-phase transformer CT connections
• Ground (zero-sequence) protection
• Directional ground protection
• Remote transfer tripping
• Thermal relays
• Gas pressure relays
• Transformer overall protection schemes
• Protection of transformers in parallel
• Reactor protection
• Shunt capacitor protection

After study of this tape and the associated workbook the participant should be able to understand the following overall concepts and apply them to his day-to-day work activities. He will also be able to answer related test questions on these subjects:

• Features of different bus arrangements
• Single breaker – single bus
• Single buses connected with bus tie breaker
• Main and transfer buses with single breaker
• Single breaker – double bus
• Double breaker – double bus
• Ring bus
• Breaker-and-a-half bus
• Special problems of bus protection
• The ground fault bus
• Partial differential protection with overcurrent relays
• Directional comparison schemes
• Residual current differential schemes
• CT saturation problems
• Multi-restraint relays
• Linear coupler
• High impedance relays

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

• Motor application: voltage levels
• Induction motor characteristics
• Torque curves: speed, slip, stall
• Potential motor hazards
• Starting arrangements
• Current – time curves
• Thermal limits for overload and start-up
• Thermal and time overcurrent protection
• Locked rotor protection
• Phase fault protection
• Ground fault protection
• Differential protection
• Protection against unbalanced conditions
• Undervoltage protection
• Synchronous motor protection

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

• Classification of lines and feeders
• Typical system configurations
• Faults on radial and loop systems
• Reclosing arrangements
• Breaker failure protection
• Application of overcurrent relays
• Setting of relay pickup and time dial
• Coordination with downstream fuses and reclosers
• Coordination procedure for loop systems
• Maximum and minimum fault levels
• Application of instantaneous overcurrent relays
• Voltage control (restraint) overcurrent relays
• Ground fault protection with directional overcurrent relays
• Polarizing sources; current; voltage
• Polarizing by negative sequence voltage
• Effects of mutual induction
• Limitations of overcurrent relays
• Characteristics of distance relays
• RX diagram
• Protection zones; primary and backup
• Multiple lines and power sources
• Tapped lines; multi-terminal lines
• Ground fault protection by distance relays
• Backup protection

After study of this tape and the associated workbook, participant should be able to understand the following overall concepts and apply them to their day-to-day work activities. They will also be able to answer related test questions on these subjects:

• Pilot wire differential protection – 60 Hz signal
• Twisted pair – solid conductors
• Distance limitations
• DC polar units
• Effect of pilot wire open circuit or short circuit
• Monitoring the pilot wire
• Drainage reactors
• Effect of ground potential rise
• Neutralizing transformer
• Communication channels
• Power line carrier; on/off mode
• PLC, frequency shift keying (FSK)
• Audio tones
• Microwave
• Fiber optics
• Direct transfer tripping
• Directional comparison under-reach
• Directional comparison overreach
• Phase comparison
• Tripping, blocking, permissive commands