Logo
Select Quick Pages:
Home
About
Contact Us
Disclaimer
Privacy policies
Terms and conditions

If the fault occurs near the impedance relay, the VI ratio will be

  • If the fault occurs near the impedance relay, the VI ratio will be lower than that of if the fault occurs away from the relay.
  • An impedance relay measures the voltage and current phasors at its location, and then calculates the impedance of the line by taking the ratio of the measured voltage and current phasors.
  • The impedance seen by the relay depends on the distance between the relay and the fault location, and the impedance of the line between the relay and the fault location.
  • When a fault occurs on the transmission line, the impedance between the fault location and the impedance relay is lower than the impedance between the relay and the source.
  • This means that the VI ratio seen by the impedance relay is lower when the fault is closer to the relay, and higher when the fault is farther away from the relay.