Siemens 7SR210 User Manual

7SR210 & 7SR220 Applications Guide
Contents
Document Release History....................................................................................................................2
Section 1: Common Functions .............................................................................................................5
1.1 Multiple Settings Groups...........................................................................................................5
1.2 Binary Inputs .............................................................................................................................6
1.3 Binary Outputs ..........................................................................................................................9
1.4 LEDs .........................................................................................................................................9
Section 2: Protection Functions.........................................................................................................11
2.1 Time delayed overcurrent (51/51G/51N) ................................................................................11
2.1.1 Selection of Overcurrent Characteristics ...................................................................12
2.1.2 Reset Delay................................................................................................................13
2.2 Voltage dependent overcurrent (51V).....................................................................................14
2.3 Cold Load Settings (51c) ........................................................................................................14
2.4 Instantaneous Overcurrent (50/50G/50N) ..............................................................................15
2.4.1 Blocked Overcurrent Protection Schemes.................................................................15
2.5 Sensitive Earth-fault Protection (50SEF) ................................................................................17
2.6 Directional Protection (67) ......................................................................................................18
2.7 Directional Earth-Fault (50/51G, 50/51N, 51/51SEF) .............................................................21
2.8 High Impedance Restricted Earth Fault Protection (64H) ......................................................22
2.9 Negative Phase Sequence Overcurrent (46NPS) ..................................................................24
2.10 Undercurrent (37)....................................................................................................................24
2.11 Thermal Overload (49)............................................................................................................24
2.12 Under/Over Voltage Protection (27/59) ..................................................................................25
2.13 Neutral Overvoltage (59N) ......................................................................................................26
2.13.1 Application with Capacitor Cone Units.......................................................................27
2.13.2 Derived NVD Voltage .................................................................................................27
2.14 Negative Phase Sequence Overvoltage (47) .........................................................................27
2.15 Under/Over Frequency (81) ....................................................................................................28
Section 3: CT Requirements ...............................................................................................................29
3.1 CT Requirements for Overcurrent and Earth Fault Protection ...............................................29
3.1.1 Overcurrent Protection CTs .......................................................................................29
3.1.2 Earth Fault Protection CTs.........................................................................................29
3.2 CT Requirements for High Impedance Restricted Earth Fault Protection..............................29
Section 4: Control Functions..............................................................................................................30
4.1 Auto-reclose Applications .......................................................................................................30
4.1.1 Auto-Reclose Example 1............................................................................................31
4.1.2 Auto-Reclose Example 2 (Use of Quicklogic with AR) ..............................................32
4.2 Quick Logic Applications.........................................................................................................33
4.2.1 Auto-Changeover Scheme Example..........................................................................33
Section 5: Supervision Functions ......................................................................................................34
5.1 Circuit-Breaker Fail (50BF) .....................................................................................................34
5.1.1 Settings Guidelines ....................................................................................................34
5.2 Current Transformer Supervision (60CTS).............................................................................36
5.3 Voltage Transformer Supervision (60VTS).............................................................................37
5.4 Trip-Circuit Supervision (74TCS)............................................................................................38
5.4.1 Trip Circuit Supervision Connections.........................................................................38
5.5 Inrush Detector (81HBL2) .......................................................................................................40
5.6 Broken Conductor / Load Imbalance (46BC)..........................................................................40
5.7 Circuit-Breaker Maintenance ..................................................................................................40
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Siemens 7SR210 Specifications

General

Brand	Siemens
Model	7SR210
Category	Relays
Language	English