Ferranti effect

Meaning

Noun

• An increase in voltage occurring at the receiving end of a long transmission line, above the voltage at the sending end. This occurs when the line is energized, but there is a very light load or the load is disconnected. The capacitive line charging current produces a voltage drop across the line inductance that is in-phase with the sending end voltages considering the line resistance as negligible.

Origin

• First observed during the installation of underground cables in Sebastian Ziani de Ferranti's 10,000 volt distribution system in 1887.