7SR210 & 7SR220 Commissioning & Maintenance Guide
© 2013 Siemens Protection Devices Limited Page 5 of 82
List of Figures
Figure 2.1-1 Directional Phase Fault Boundary System Angles ................................................... 16
Figure 2.2-1 Phase Overcurrent ..................................................................................................... 17
Figure 2.3-1 Voltage Controlled Overcurrent ................................................................................. 20
Figure 2.4-1 Cold Load ................................................................................................................... 22
Figure 2.4-2 Cold Load Logic diagram ........................................................................................... 23
Figure 2.1-1 Arc Flash Detection .................................................................................................... 25
Figure 2.5-1 Directional Earth Fault Boundary System Angles .................................................... 26
Figure 2.6-1 Derived Earth Fault .................................................................................................... 27
Figure 2.7-1 Measured Earth Fault ................................................................................................. 31
Figure 2.8-1 Sensitive Earth Fault .................................................................................................. 35
Figure 2.9-1 Restricted Earth Fault ................................................................................................ 39
Figure 2.10-1 Negative Phase Sequence Overcurrent .............................................................. 41
Figure 2.11-1 Undercurrent ........................................................................................................ 44
Figure 2.12-1 Thermal Overload ................................................................................................ 46
Figure 2.13-1 Phase Under/Over Voltage .................................................................................. 48
Figure 2.13-2 Vx Under/Over Voltage ........................................................................................ 51
Figure 2.13-3 NPS Overvoltage .................................................................................................. 53
Figure 2.13-4 Neutral Overvoltage ............................................................................................. 55
Figure 2.13-5 Under/Over Frequency ........................................................................................ 57
Figure 2.11-1 Power ................................................................................................................... 59
Figure 2.12-1 Sensitive Power ................................................................................................... 61
Figure 2.13-1 Power Factor ........................................................................................................ 63
Figure 3.1-1 CB Fail ........................................................................................................................ 65
Figure 3.2-1 Voltage Transformer Supervision.............................................................................. 67
Figure 3.3-1 Current Transformer Supervision.............................................................................. 69
Figure 3.4-1 Broken Conductor ...................................................................................................... 71
Figure 3.5-1 Load Blinder (21) ........................................................................................................ 73
Figure 3.5-2 Load Blinder (21) Boundary Points ........................................................................... 74
Figure 3.6-1 Trip Circuit Supervision ............................................................................................. 77
Figure 3.7-1 Magnetising Inrush Detector ..................................................................................... 78
Figure 3.1-1 Magnetising Inrush Detector ..................................................................................... 79