Siemens SIPROTEC 4 Manual page 75

Table 2-7
Parameter OPERRAT. MODE
Setting
1-phase
3-phase
3-phase
Without Reference
Measurement Process
The following table lists configurable measurement procedures depending on parameterized measured quan-
tities.
Table 2-8
Parameter OPERRAT. MODE = 3-phase
Parameter MEAS. QUANTITY = Voltage
Parameter MEAS. METHOD
Fundamental
True RMS
Positive seq.,
Negative seq.,
Zero sequence
Parameter MEAS. QUANTITY = Voltage
Parameter VOLTAGE
SYSTEM
Phase-Phase
Phase-Ground
SIPROTEC 4, 7RW80, Manual
C53000-G1140-C233-4, Edition 07.2018
Parameter OPERRAT. MODE and MEAS. QUANTITY
Parameter MEAS. QUANTITY
Setting Options
Voltage
dV/dt rising
dV/dt falling
Frequency
df/dt rising
df/dt falling
Binray Input
Parameter in the Setting Dialog "Measurement Procedure", Mode of Operation 3-phase
Only the fundamental harmonic is evaluated, higher harmonics are suppressed. This is
the standard measurement procedure of the protection functions.
Important: The voltage threshold value is always parameterized as phase-to-phase
voltage. If parameter VOLTAGE SYSTEM is selected as phase-to-ground, the voltage
threshold will be devided by √3.
The "true" RMS value is determined, i.e. higher harmonics are evaluated.
Important: The voltage threshold value is always parameterized as phase-to-phase
voltage. If parameter VOLTAGE SYSTEM is selected as phase-to-ground, the voltage
threshold will be devided by √3.
In order to realize certain applications, the positive sequence system or negative
sequence system can be configured as measurement procedure for example U2 (voltage
asymmetry)
Via the selection zero sequence system, additional zero sequence voltage functions can
be realized that operate independent of the ground variable V
directly via transformers.
Important: The voltage threshold is always parameterized according to the definition of
the balanced components independently of parameter VOLTAGE SYSTEM.
If you have configured address 213 VT Connect. 3ph to Van, Vbn, Vcn or Vab,
Vbc, VGnd, you can select whether a 3- phase voltage function will evaluate the phase-
to-ground voltage or the phase-to-phase voltages.
When selecting phase-to-phase, these variables are derived from the phase-to-ground
voltages. The selection is, for example, important for single-pole faults. If the faulty
voltage drops to zero, the affected phase-to-ground voltage is zero, whereas the affected
phase-to-phase voltages collapse to the size of a phase-to-ground voltage.
With phase-to-phase voltage connections the parameter is hidden.
Functions
2.6 Flexible Protection Functions
, which are measured
N
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