Power-Line Carrier is one of the most reliable and economical choices available for pilot relaying and transfer trip applications: 

• Reliability proven by more than fifty years of field experience at Electric Utilities all over the world. 
• Economic because it uses the power line itself as the medium, thereby not requiring expensive alternatives such as microwave, leased circuits or fiber optics. 
• Today, more transmission lines around the globe rely on Power-Line Carrier (PLC) for relay communications than any other method.

Applying PLC requires no licensing or right-of-way negotiations. In many cases the utility engineer can design, specify and install a PLC system without involving any other departments. For a new installation, the PLC channel is guaranteed to be ready before line energization since it uses the line itself for its communication path.

PLC, like other types of channels, works closely with protective relay systems to provide high speed clearing of internal line faults while restricting tripping for external faults. Channel logic, within the relay system, allows coordinating for identifying end zone faults, weak infeed conditions and current reversals.

• Jumper Position and Setting sheets for TC-10B and TCF-10B ( 177k)