7SR210 & 7SR220 Applications Guide
© 2013 Siemens Protection Devices Limited
Page 45 of 48
5.10.2 Design View
5.10.2.1
Load Blinder 3Ph
Figure 5.10.2.1-1 Logic Diagram 3 Phase
The 3-phase load blinder has the following setting parameters:
21LB – 3P Angle +ve
21LB – 3P Angle -ve
21LB – 3P Impedance
21LB – 3P VPPS
21LB – 3P INPS
The design of Load Blinder 3Ph takes into consideration that the protection blocking should only be issued during
definable allowable system power flow conditions i.e. an overcurrent blocking signal can only be issued when:
a. Positive Sequence Voltage
Vpps
is not significantly reduced i.e. is above the
21LB-3P VPPS Setting.
AND
b. Negative Sequence Current
Inps
is lower than
21LB-3P INPS Setting
AND
c. The impedance measured in all phases is within the operate zone.
Zpps
is calculated from
Vpps
and
Ipps
. The calculated
Zpps
is used to determine if the impedance is in
the operate zone i.e. greater than the
21LB-3P Impedance
setting and less than the
21LB-3P Angle
settings. Suitable settings can be chosen to provide overcurrent blocking in the forward or reverse
directions.
Summary of Contents for Argus 7SR21
Page 1: ...Energy Management 7SR21 7SR22 Argus Overcurrent Relay Reyrolle Protection Devices ...
Page 2: ......
Page 4: ...Contents 7SR11 and 7SR12 Page 2 of 2 2018 Siemens Protection Devices Limited ...
Page 185: ...7SR210 Settings Guide Unrestricted 2018 Siemens Protection Devices Limited Page 61 of 61 ...
Page 277: ...7SR220 Settings Guide Unrestricted Page 72 of 107 2013 Siemens Protection Devices Limited ...
Page 382: ...7SR220 Technical Manual Chapter 4 Page 2 of 96 2017 Siemens Protection Devices Limited ...
Page 386: ...7SR220 Technical Manual Chapter 4 Page 6 of 96 2017 Siemens Protection Devices Limited ...
Page 398: ...7SR220 Technical Manual Chapter 4 Page 18 of 96 2017 Siemens Protection Devices Limited ...
Page 414: ...7SR220 Technical Manual Chapter 4 Page 34 of 96 2017 Siemens Protection Devices Limited ...
Page 466: ...7SR220 Technical Manual Chapter 4 Page 86 of 96 2017 Siemens Protection Devices Limited ...
Page 468: ...7SR220 Technical Manual Chapter 4 Page 88 of 96 2017 Siemens Protection Devices Limited ...
Page 470: ...7SR220 Technical Manual Chapter 4 Page 90 of 96 2017 Siemens Protection Devices Limited ...
Page 472: ...7SR220 Technical Manual Chapter 4 Page 92 of 96 2017 Siemens Protection Devices Limited ...
Page 643: ...Unrestricted ...