Settings - Siemens SIPROTEC 4 7UT6 Series Manual

The function is based on the asymmetic differential current. If the content of asymmetry of two phases
exceeds the allowed degree of asymmetry, differential protection will be blocked. In order to prevent a mal-
function under single phase earthed fault, another degree of asymmetry the max phase criterion is used to
unblock this logic.
The restraint with harmonics does not influence the stage I-DIFF>>.
See following logic diagram for the details:
[lo_cwa-7utx, 1, en_GB]
Figure 2-51
NOTE
i
i
The current values Ι/Ι
protected object. The current values Ι/Ι
protected object.

Settings

2.2.8
Addresses which have an appended "A" can only be changed with DIGSI, under "Additional Settings".
Addr. Parameter
1201 DIFF. PROT.
1205 INC.CHAR.START
1206 INRUSH 2.HARM.
1207 RESTR. n.HARM.
1208 I-DIFF> MON.
1210 I> CURR. GUARD
1211A DIFFw.IE1-MEAS
1212A DIFFw.IE2-MEAS
SIPROTEC 4, 7UT6x, Manual
C53000-G1176-C230-5, Edition 09.2016
Logic Current Waveform Analysis Restraint (CWA)
in the settings overview below always refer to the rated current of the main
NO
NS
Setting Options
OFF
ON
Block relay
OFF
ON
OFF
ON
OFF
3. Harmonic
5. Harmonic
OFF
ON
0.20 .. 2.00 I/InS; 0
NO
YES
NO
YES
always refer to the rated current of the relevant side of the main
Default Setting
OFF
OFF
ON
OFF
ON
0.00 I/InS
NO
NO
Functions
2.2 Differential Protection
Comments
Differential Protection
Increase of Trip Char. During Start
Inrush with 2. Harmonic Restraint
n-th Harmonic Restraint
Differential Current monitoring
I> for Current Guard
Diff-Prot. with meas. Earth Current
S1
Diff-Prot. with meas. Earth Current
S2
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