Functions
2.2 Voltage Protection 27, 59
SIPROTEC, 7RW80, Manual
C53000-G1140-C233-1, Release date 10.2010
45
2.2.4 Setting Notes
General
Voltage protection is only in effect and accessible if address 150 27/59 is set to Enabled during configuration
of protective functions. If the function is not required Disabled is set.
The voltage to be evaluated is selected in Power System Data 1 (see Chapter 2.2, Table 2-2).
Overvoltage protection can be turned ON or OFF or set to Alarm Only at address 5001 FCT 59.
Undervoltage protection can be turned ON or OFF or set to Alarm Only at address 5101 FCT 27.
With the protection function ON tripping, fault record and fault recording will occur when limit values were ex-
ceeded and after time delays expired.
When setting Alarm Only no trip command is given, no fault is recorded and no spontaneous fault annunci-
ation is shown on the display.
For over-voltage and under-voltage protection user-defined curves with 20 value pairs (voltage/time) may be
configured. Usage of a curve has to be activated at address 5035 Pickup - Time for the element 59 Vp>
and at address 5133 Pickup - Time for the element 27 Vp<.
Overvoltage Protection (59-1, 59-2) with phase-to-phase / phase-to-ground voltage
For over-voltage protection with phase-to-phase or phase-to-ground voltages you have to configure at address
5009 59 Phasesthe measured quantity that is to be evaluated for the over voltage protection. While being
configured All phases all voltages have to exceed their threshold. At Largest phase only one voltage has
to exceed its threshold.
The threshold values are set in the value to be evaluated (see Chapter 2.2, Table 2-2).
Overvoltage protection includes three elements. The pickup value of the lower threshold is set at address 5002
or 5003, 59-1 PICKUP, (depending on if the phase-to-ground or the phase-to-phase voltages are connected),
while time delay is set at address 5004, 59-1 DELAY (a longer time delay). The pickup value of the upper
element is set at address 5005 or 5006,
59-2 PICKUP, while the time delay is set at address 5007, 59-2
DELAY (a short time delay). A third element can be activated at address 5031 59 Vp>, which works with a
user-defined curve (address 5035).
There are not clear cut procedures on how to set the pickup values. However, since the overvoltage function
is primarily intended to prevent insulation damage on equipment and loads, the setting value 5002 , 5003 59-
1 PICKUP should be set between 110 % and 115 % of nominal voltage, and setting value 5005, 5006 59-2
PICKUP should be set to about 130 % of nominal voltage.
The time delays of the overvoltage elements are entered at addresses 5004 59-1 DELAY, 5007 59-2 DELAY
and 5034 59 T Vp> and should be selected to allow the brief voltage spikes that are generated during switch-
ing operations and to enable clearance of stationary overvoltages in time.
The option to choose between phase-to-ground and phase-to-phase voltage, allows voltage asymmetries (e.g.
caused by a ground fault) to be taken into account (phase-ground) or to remain unconsidered (phase–phase)
during evaluation.
Overvoltage Protection - Positive Sequence System V1
In a three-phase voltage transformer connection the positive sequence system can be evaluated for the over-
voltage protection by means of configuring parameter 614 OP. QUANTITY 59 to V1. In this case, the threshold
values of the overvoltage protection must be set in parameters 5019 59-1 PICKUP V1 or 5020 59-2
PICKUP V1. A third element can be activated at address 5032 59 Vp> V1, which works with a user-defined
curve (address 5035).
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