Siemens 7SR242 Duobias Technical Manual page 11

List of Figures
Figure 1-1 Function Diagram: 7SR242n-2aAnn-0AA0 Relay ........................................................... 10
Figure 1-2 Function Diagram: 7SR242n-2aAnn-0BA0 Relay ........................................................... 11
Figure 1-3 Function Diagram: 7SR242n-2aAnn-0CA0 Relay ........................................................... 12
Figure 1-4 Connection Diagram: 7SR242 Relay ............................................................................. 13
Figure 2-1 7SR24 with 3 + 16 LEDs in E8 Case ............................................................................ 16
Figure 2-2 Binary Input Logic......................................................................................................... 19
Figure 2-3 Binary Output Logic ...................................................................................................... 21
Figure 2.11-1 Start-up Counter Meter ................................................................................................ 22
Figure 3-1 Biased Differential Characteristic ................................................................................... 24
Figure 3-2 Functional Diagram for Biased Current Differential Protection ........................................ 25
Figure 3-3 Differential Highset Characteristic .................................................................................. 26
Figure 3-4 Logic Diagram: High Set Current Differential Protection ................................................. 27
Figure 3-5 Logic Diagram: Instantaneous Over-current Element ..................................................... 28
Figure 3-6 Logic Diagram: Time Delayed Overcurrent Element....................................................... 29
Figure 3-7 Logic Diagram: Instantaneous Derived Earth Fault Element........................................... 30
Figure 3-8 Logic Diagram: Derived Time Delayed Earth Fault Protection ........................................ 31
Figure 3-9 Logic Diagram: Measured Instantaneous Earth-fault Element ........................................ 32
Figure 3-10 Logic Diagram: Time Delayed Measured Earth Fault Element (51G) .............................. 33
Figure 3-11 Logic Diagram: High Impedance REF (64H) .................................................................. 34
Figure 3-12 Logic Diagram: Open Circuit Function (46BC) ............................................................... 35
Figure 3-13 Logic Diagram: Negative Phase Sequence Overcurrent (46NPS) .................................. 36
Figure 3-14 Logic Diagram: Undercurrent Detector (37, 37G) ........................................................... 37
Figure 3-15 Logic Diagram: Thermal Overload Protection (49) ......................................................... 39
Figure 3-16 Inverse Over-fluxing Characteristic (24IT) ...................................................................... 40
Figure 3-17 Logic Diagram: Overfluxing Elements (24) ..................................................................... 41
Figure 3-18 Logic Diagram: Under/Over Voltage Elements (27/59) ................................................... 42
Figure 3-19 Logic Diagram: Neutral Overvoltage Element ................................................................ 43
Figure 3-20 Logic Diagram: Under/Over Frequency Detector (81) .................................................... 44
Figure 4-1 Sequence Diagram showing PU/DO Timers in Quick Logic (Counter Reset
Mode Off) ...................................................................................................................... 46
Figure 5-1 Logic Diagram: Circuit Breaker Fail Protection (50BF) ................................................... 48
Figure 5-2 Logic Diagram: Trip Circuit Supervision Feature (74TCS) .............................................. 49
Figure 5-3 Logic Diagram: Close Circuit Supervision Feature (74CCS) ........................................... 49
Figure 5-4 Logic Diagram: Inrush Detector Feature (81HBL2) ........................................................ 50
Figure 5-5 Logic Diagram: Overfluxing Detector Feature (81HBL5) ................................................. 51
List of Tables
Table 1-1: 7SR242 Ordering Options .................................................................................................. 8
Table 2-1 Summary of 7SR24 Relay Configurations ...................................................................... 15
Table 6-1 Operating Mode ............................................................................................................ 57
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Chapter 1) 7SR242 Duobias Description Of Operation
Chapter 1 Page 5 of 60