Disturbance recorder

The relay is provided with a disturbance recorder featuring up to

24 analog and 64 binary signal channels. The analog channels

can be set to record either the waveform or the trend of the

currents and voltages measured.

The analog channels can be set to trigger the recording function

when the measured value falls below or exceeds the set values.

The binary signal channels can be set to start a recording either

on the rising or the falling edge of the binary signal or on both.

The binary channels can be set to record external or internal

relay signals, for example, the start or trip signals of the relay

stages, or external blocking or control signals. The recorded

information is stored in a nonvolatile memory in COMTRADE

format and can be uploaded for subsequent fault analysis.

Fault locator

The relay features an optional impedance-measuring fault

location function suitable for locating short circuits in radial

distribution systems. Earth faults can be located in effectively

and low-resistance earthed networks, as well as in

compensated networks. When the fault current magnitude is at

least of the same order of magnitude or higher than the load

current, earth faults can also be located in isolated neutral

distribution networks. The fault location function identifies the

type of the fault and then calculates the distance to the fault

point. The calculations provide information on the fault

resistance value and accuracy of the estimated distance to the

fault point.