The relay basically consists of an instantaneous overvoltage unit that is set by
calculating the maximum voltage at the relay terminals for an external fault, taking
into account the maximum primary fault current, the resistance of the secondary
windings and the wiring, and the transformation ratios of the CTs, plus a safetymargin.
Consequently, during an external fault, the voltage across the terminals of the relay is
relatively low and does not initiate any relay operation. During internal faults, the
voltage across the relay terminals is higher and results in the operation of the instantaneous
overvoltage unit that sends a tripping signal to the appropriate breakers.
The relay basically consists of an instantaneous overvoltage unit that is set bycalculating the maximum voltage at the relay terminals for an external fault, takinginto account the maximum primary fault current, the resistance of the secondarywindings and the wiring, and the transformation ratios of the CTs, plus a safetymargin.Consequently, during an external fault, the voltage across the terminals of the relay isrelatively low and does not initiate any relay operation. During internal faults, thevoltage across the relay terminals is higher and results in the operation of the instantaneousovervoltage unit that sends a tripping signal to the appropriate breakers.
การแปล กรุณารอสักครู่..
