Functions
2.1 General
SIPROTEC, 7SC805, Manual
C53000-G1140-C380-1, Release date 05.2014
25
Nominal Values of Voltage Transformers (VTs) (Only For 3-phase System)
At addresses
202
Vnom PRIMARY
and
203
Vnom SECONDARY
, information is entered regarding the primary
nominal voltage and secondary nominal voltage (phase-to-phase) of the connected voltage transformers.
At addresses
333
Vnom prim
V
x
and
325
Vnom sec
V
x
, you can enter the primary and secondary rated voltage
for the 4th voltage input Vx.
Current Clipping Limit Ratio
Address
480
ClipC
informs the ratio of the clipping limit of the instantaneous current to the rated primary voltage
multiplied with a square root of two. For example “clip=20” applied with rated primary current of IP
r
=500A
RMS
means clipping will occur at ±14140A
PEAK.
Primary currents with magnitude above the clipping limit may satu-
rate analogue circuits and/or digital filters within the instrument transformer resulting in highly inaccurate
sampled values
Voltage Clipping Limit Ratio
Address
481
ClipV
informs the ratio of the clipping limit of the instantaneous voltage to the rated primary voltage
multiplied with a square root of two. For example “clip=2” applied with rated primary voltage of UP
r
=5 kV
RMS
means clipping may occur at ±14.14 kV
PEAK
. Primary voltages with magnitude above the clipping limit may sat-
urate analogue circuits and/or digital filters within the instrument transformer resulting in highly inaccurate
sampled values
Nominal Values of Voltage Transformers (VTs) (Only For 1-phase System)
Currently 4 channels voltage are supported. Every channel has its own configuration. Address
570, 572, 574,576
are for Channel Rated Primary Volatge Values, and Address
571,573,575, 577
are for Channel Rated Second
Voltage Values. At these addresses, information is entered regarding to the primary nominal voltage and sec-
ondary nominal voltage (phase independent) of the connected voltage transformers
2.1.2.3
Settings
The table indicates region-specific default settings.
For clear reference, parameters for 1-phase and 3-phase are listed respectively.
Table 3: Settings For 3-phase Ratio
Addr.
Parameter
C
Setting Options
Default Setting
Comments
202
Vnom PRIMARY
0.10 .. 800.00 kV 20.00 kV
Rated Primary Voltage
203
Vnom
SECONDARY
34 .. 400 V
100 V
Rated Secondary Voltage (L-L)
204
CT PRIMARY
10 .. 50000 A
400 A
CT Rated Primary Current
205
CT SECONDARY
1 A
5 A
1A
CT Rated Secondary Current
214
Rated Frequency
50 Hz
60 Hz
50Hz
Rated Frequency
217
Ignd-CT PRIM
1 .. 50000 A
400 A
Ignd-CT rated primary current
218
Ignd-CT SEC
1 A
5 A
1 A
Ignd-CT rated secondary
current
325
Vnom sec Vx
34 .. 230 kV
100 kV
Rated Secondary Voltage Vx