Siemens 7SR18 Solkor - Page 304

7SR18 Commissioning & Maintenance Guide
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List of Figures
Figure 2.1-1 Biased Differential ......................................................................................................... 12
Figure 2.3-1 Loop Test Mode ............................................................................................................ 14
Figure 2.3-2 Line Test Mode ............................................................................................................. 14
Figure 2.3-3 Secondary Injection ....................................................................................................... 15
Figure 2.6-1 Primary Injection Phase to Earth ................................................................................... 16
Figure 2.6-2 Primary Injection Phase to Phase .................................................................................. 17
Figure 3.1-1 Phase Overcurrent ........................................................................................................ 21
Figure 3.4-1 Cold Load ..................................................................................................................... 25
Figure 3.4-2 Cold Load Logic diagram ............................................................................................... 26
Figure 3.5-1 Derived Earth Fault ....................................................................................................... 29
Figure 3.6-1 Measured Earth Fault .................................................................................................... 33
Figure 3.7-1 Negative Phase Sequence Overcurrent ......................................................................... 37
Figure 3.8-1 Undercurrent ................................................................................................................. 40
Figure 3.9-1 Thermal Overload.......................................................................................................... 42
Figure 4.1-1 CB Fail .......................................................................................................................... 44
Figure 4.2-1 Current Transformer Supervision ................................................................................... 46
Figure 4.3-1 Broken Conductor ......................................................................................................... 47
Figure 4.4-1 Trip Circuit Supervision ................................................................................................. 49
Figure 4.5-1 Magnetising Inrush Detector .......................................................................................... 50
List of Tables
Table 6.3-1 Troubleshooting Guide .................................................................................................. 53