Siemens 7SR10 Argus Series Manual page 247

List of Figures
Figure 1-1 Example Use of Alternative Settings Groups ................................................................................. 4
Figure 1-2 Example of Transformer Alarm and Trip Wiring ............................................................................. 5
Figure 1-3 LED configuration via the LED Matrix tab ...................................................................................... 7
Figure 1-4 LED configuration via the Settings \ OUTPUT CONFIG \ LED CONFIG menu ................................ 7
Figure 2-1 IEC NI Curve with Time Multiplier and Follower DTL Applied ......................................................... 8
Figure 2-2 IEC NI Curve with Minimum Operate Time Setting Applied ............................................................ 9
Figure 2-3 Reset Delay ............................................................................................................................... 10
Figure 2-4 Arc Flash Detection .................................................................................................................... 12
Figure 2-5 General Form of DTL Operate Characteristic............................................................................... 12
Figure 2-6 Blocking Scheme Using Instantaneous Overcurrent Elements ..................................................... 13
Figure 2-7 Sensitive Earth Fault Protection Application ................................................................................ 14
Figure 2-8 Directional Characteristics .......................................................................................................... 15
Figure 2-9 Phase Fault Angles .................................................................................................................... 16
Figure 2-10 Application of Directional Overcurrent Protection ......................................................................... 16
Figure 2-11 Feeder Fault on Interconnected Network ..................................................................................... 17
Figure 2-12 Earth Fault Angles ...................................................................................................................... 18
Figure 2-13 Earth fault current distribution in Compensated network ............................................................... 18
Figure 2-14 Earth fault current direction in compensated network ................................................................... 19
Figure 2-15 Adjustment of Characteristic Angle.............................................................................................. 19
Figure 2-16 Cosine component of current ...................................................................................................... 19
Figure 2-17 Earth fault current in isolated network.......................................................................................... 20
Figure 2-18 Balanced and Restricted Earth-fault protection of Transformers ................................................... 21
Figure 2-18 Composite Overcurrent and Restricted Earth-fault Protection ....................................................... 22
Figure 2-20 Thermal Overload Heating and Cooling Characteristic ................................................................. 23
Figure 2-21 NVD Application ......................................................................................................................... 25
Figure 2-22 NVD Protection Connections ...................................................................................................... 25
Figure 2-23 Load Shedding Scheme Using Under-Frequency Elements ......................................................... 27
Figure 4-1 Sequence Co-ordination ............................................................................................................. 29
Figure 4-2 Example of Logic Application ...................................................................................................... 31
Figure 4-3 Example Use of Quick Logic ....................................................................................................... 32
Figure 5-1 Circuit Breaker Fail ..................................................................................................................... 33
Figure 5-2 Single Stage Circuit Breaker Fail Timing ..................................................................................... 34
Figure 5-3 Two Stage Circuit Breaker Fail Timing ........................................................................................ 34
Figure 5-4 Logic Diagram: Trip Circuit Supervision Feature (74TCS) ............................................................ 37
Figure 5-5 Logic Diagram: Close Circuit Supervision Feature (74CCS) ......................................................... 37
Figure 5-6 Trip Circuit Supervision Scheme 1 (H5) ....................................................................................... 38
Figure 5-7 Trip Circuit Supervision Scheme 2 (H6) ....................................................................................... 38
Figure 5-8 Trip Circuit Supervision Scheme 3 (H7) ....................................................................................... 39
Figure 5-9 Close Circuit Supervision Scheme .............................................................................................. 39
List of Tables
Table 2-1 Application of IDMTL Characteristics ........................................................................................... 10
Table 5-1 Determination of VT Failure (1 or 2 Phases) ................................................................................ 35
Table 5-2 Determination of VT Failure (1 or 2 Phases) ................................................................................ 36
Table 5-3 Determination of VT Failure (3 Phases) ....................................................................................... 36
Table 5-4 Magnetic Inrush Bias .................................................................................................................. 40
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7SR10, 7SR11, 7SR12 Applications Guide
Chapter 7 Page 3 of 41