System Protection Technology

The purpose of this videotape is to familiarize participants with the principles of pilot protection, the various schemes used and the different types of communication channels employed.

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