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7. Measurement
The relay continuously measures the phase currents and the
neutral current. Furthermore, the relay measures the phase
voltages and the residual voltage. Depending on the standard
configuration, the relay also offers frequency measurement. In
addition, the relay calculates the symmetrical components of
the currents and voltages, maximum current demand value
over a user-selectable pre-set time frame, the active and reac-
tive power, the power factor and the active and reactive energy
values. Calculated values are also obtained from the protection
and condition monitoring functions of the relay.
The measured values can be accessed via the local HMI or re-
motely via the communication interface of the relay. The values
can also be accessed locally or remotely using the Web HMI.
The relay is provided with a load profile recorder. The load pro-
file feature stores the historical load data captured at a peri-
odical time interval (demand interval). The records are in COM-
TRADE format.
8. Disturbance recorder
The relay is provided with a disturbance recorder featuring up
to 12 analog and 64 binary signal channels. The analog chan-
nels 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 func-
tion when the measured value falls below or exceeds the set
values. The binary signal channels can be set to start a record-
ing either on the rising or the falling edge of the binary signal
or on both.
By default, the binary channels are set to record external or in-
ternal relay signals, for example, the start or trip signals of the
relay stages, or external blocking or control signals. Binary re-
lay signals, such as protection start and trip signals, or an ex-
ternal relay control signal via a binary input, can be set to trig-
ger the recording. Recorded information is stored in a
non-volatile memory and can be uploaded for subsequent fault
analysis.
9. Event log
To collect sequence-of-events information, the relay has a non-
volatile memory capable of storing 1024 events with the asso-
ciated time stamps. The non-volatile memory retains its data
even if the relay temporarily loses its auxiliary supply. The
event log facilitates detailed pre- and post-fault analyses of
feeder faults and disturbances. The considerable capacity to
process and store data and events in the relay facilitates meet-
ing the growing information demand of future network config-
urations.
The sequence-of-events information can be accessed either
via local HMI or remotely via the communication interface of
the relay. The information can also be accessed locally or re-
motely using the Web HMI.
10. Recorded data
The relay has the capacity to store the records of the 128 latest
fault events. The records can be used to analyze the power sys-
tem events. Each record includes, for example, current, voltage
and angle values and a time stamp. The fault recording can be
triggered by the start or the trip signal of a protection block,
or by both. The available measurement modes include DFT,
RMS and peak-to-peak. Fault records store relay measurement
values at the moment when any protection function starts. In
addition, the maximum demand current with time stamp is
separately recorded. The records are stored in the non-volatile
memory.
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