116
1MRS751802-MUM
Protection Relay
Technical Reference Manual, Standard Configurations
REX 521
7.3.2.
Io
The neutral current measurement function block Io measures the true RMS neutral
current, that is, harmonics are not suppressed. The current values are updated once
a fundamental frequency cycle, that is, the integration time for the true RMS
calculation is one fundamental cycle
.
Fig. 7.3.2.-1
Function block symbol of Io
7.3.3.
Uo
The function block Uo measures the true RMS residual voltage, that is, harmonics
are not suppressed. The voltage value is updated once a fundamental frequency
cycle, that is, the integration time for the true RMS calculation, is one fundamental
cycle.
Fig. 7.3.3.-1
Function block symbol of Uo
7.3.4.
DREC
The transient disturbance recorder DREC is used for recording current waveforms
and, when available, voltage waveforms. Furthermore, start and trip signals from the
protection functions are recorded. The amount of recorded signals is standard
configuration specific; refer to the block diagram of the standard configuration.
The default setting for the analogue channels recorded in DREC does not include I
0b
measurement. When I
0b
is in use and it is wanted to record data, the used analogue
channel setting has to be changed in
Main menu\Measurement\DREC\
General info\AI chs used
.
Neutral current measurement, Io
Io (A)
Io (%)
0.0…20000.0 A
0.0…80.0% In
Io
Io
Residual voltage measurement, Uo
Uo
Uo
0…150000 V
0.0…120.0% Un
Uo
Uo
Содержание REX 521
Страница 1: ...Protection Relay REX 521 Technical Reference Manual Standard Configurations ...
Страница 2: ......
Страница 12: ...12 ...
Страница 22: ...22 ...
Страница 62: ...62 ...
Страница 72: ...72 ...
Страница 128: ...128 ...
Страница 132: ...132 ...
Страница 172: ...172 ...
Страница 198: ...198 ...
Страница 249: ......