Siemens 7SR224 Technical Manual page 228

Contents
Section 1: Common Functions .............................................................................................................5
1.1 Overview ...................................................................................................................................5
1.2 Before Testing...........................................................................................................................5
1.2.1 Safety ...........................................................................................................................5
1.2.2 Sequence of Tests .......................................................................................................5
1.2.3 Test Equipment ............................................................................................................6
1.2.4 Precautions ..................................................................................................................6
1.2.5 Applying Settings .........................................................................................................6
1.3 Tests .........................................................................................................................................8
1.3.1 Inspection .....................................................................................................................8
1.3.2 Secondary Injection Tests............................................................................................8
1.3.3 Primary Injection Tests.................................................................................................8
1.3.4 Putting into Service ......................................................................................................8
1.4 AC Energising Quantities..........................................................................................................9
1.5 Binary Inputs ...........................................................................................................................10
1.6 Binary Outputs ........................................................................................................................11
1.7 Relay Case Shorting Contacts................................................................................................12
Section 2: Protection Functions .........................................................................................................13
2.1 Phase Directional Polarity Check............................................................................................14
2.1.1 2 out of 3 logic............................................................................................................16
2.2 Phase Overcurrent (67/50,67/51) ...........................................................................................16
2.2.1 Definite Time Overcurrent
2.2.2 Inverse Time Overcurrent (51) .................................................................................17
2.3 Voltage Controlled Overcurrent (51V) ....................................................................................19
2.4 Cold Load (51C)......................................................................................................................21
2.4.1 Inverse Time Overcurrent (51C) ..............................................................................22
2.5 Directional Earth Fault Polarity Check (67N) ..........................................................................24
2.6 Measured Earth fault (67/50G,67/51G) ..................................................................................25
2.6.1 Directional Polarity .....................................................................................................26
2.6.2 Definite Time Overcurrent
2.6.3 Inverse Time Overcurrent (67/51G) .........................................................................26
2.7 Sensitive Earth fault (67/50S,67/51S).....................................................................................29
2.7.1 Directional Polarity .....................................................................................................30
2.7.2 Definite Time Overcurrent
2.7.3 Inverse Time Overcurrent (51SEF)..........................................................................30
2.8 Restricted Earth fault (64H) ..................................................................................................33
2.9 Negative Phase Sequence Overcurrent (46NPS) ..................................................................35
2.9.1 Definite Time NPS Overcurrent
2.9.2 Inverse Time NPS Overcurrent (46IT) .....................................................................36
2.10 Undercurrent (37)..................................................................................................................38
2.11 Thermal Overload (49)............................................................................................................40
2.12 Over/Under Voltage ................................................................................................................42
2.12.1 Phase Under/Over Voltage (27/59)...........................................................................42
2.12.2 Undervoltage Guard (27/59UVG) ..............................................................................44
2.12.3 Vx Under/Over Voltage (Vx 27/59) ..........................................................................45
2.12.4 NPS Overvoltage (47) ................................................................................................47
2.12.5 Neutral Overvoltage (59N) .........................................................................................49
2.12.6 Definite Time (59NDT) ...............................................................................................49
2.12.7 Inverse Time (59NIT) .................................................................................................50
2.12.8 Under/Over Frequency (81) .......................................................................................51
Section 3: Supervision Functions ......................................................................................................53
3.1 CB Fail (50BF) .......................................................................................................................53
©2010 Siemens Protection Devices Limited
7SR224 Argus Commissioning & Maintenance Guide
(50) ...............................................................................17
(67/50G)........................................................................26
(50SEF) ........................................................................30
(46DT) ..................................................................36
Chapter 6 Page 2 of 73