Table Of Contents - Siemens 7SR105 Rho User Manual

Motor protection relay

page of 205

/ 205
Contents
Table of Contents
Bookmarks

Table of Contents

Contents

Section 1: Introduction ....................................................................................................................................... 6

1.1 Current Transformer Circuits .............................................................................................................. 6

1.2 External Resistors.............................................................................................................................. 6

1.3 Description ........................................................................................................................................ 6

1.4 Ordering Options ............................................................................................................................... 7

1.5 Functional Diagram ............................................................................................................................ 8

1.6 Terminal Diagram .............................................................................................................................. 9

1.6.1

Terminal Diagram with Control Push Buttons ........................................................................ 9

Section 2: Hardware Description ...................................................................................................................... 10

2.1 General ........................................................................................................................................... 10

2.2 Front Fascia .................................................................................................................................... 11

2.2.1

Front Fascia with Control Push Buttons ............................................................................... 11

2.3 Start Motor/Stop Motor ..................................................................................................................... 11

2.4 Power Supply Unit (PSU) ................................................................................................................. 12

2.5 Connectors ...................................................................................................................................... 12

2.5.1

Connectors without Temperature Inputs .............................................................................. 13

2.5.2

Connectors with Temperature Inputs ................................................................................... 13

2.6 Relay Information ............................................................................................................................ 14

2.7 Operator Interface............................................................................................................................ 15

2.7.1

Liquid Crystal Display (LCD) ............................................................................................... 15

2.7.2

LCD Indication ................................................................................................................... 15

2.7.3

Standard Keys ................................................................................................................... 16

2.7.4

Protection Healthy LED ...................................................................................................... 16

2.7.5

Indication LEDs .................................................................................................................. 16

2.8 Current Inputs.................................................................................................................................. 17

2.9 Binary Inputs ................................................................................................................................... 18

2.10 Binary Outputs (Output Relays) ........................................................................................................ 18

2.11 Virtual Input/Outputs ........................................................................................................................ 19

2.12 Self Monitoring ................................................................................................................................ 20

2.12.1

Protection Healthy/Defective ............................................................................................... 21

Section 3: Protection Functions ........................................................................................................................ 22

3.1 Thermal Protection .......................................................................................................................... 22

3.1.1

Thermal Protection: Overload (49) ...................................................................................... 24

3.1.2

Thermal Protection: Stall Protection (14) ............................................................................. 27

3.1.3

Thermal Protection: Start Protection (48, 66) ....................................................................... 28

3.1.4

Thermal Protection: Phase Unbalance (46) ......................................................................... 30

3.2 Current Protection: Undercurrent (37) ............................................................................................... 33

3.3 Current Protection: Phase Overcurrent (50, 51) ................................................................................ 33

3.3.1

Instantaneous Overcurrent Protection (50) .......................................................................... 33

3.3.2

Time Delayed Overcurrent Protection (51) .......................................................................... 34

3.4 Current Protection: Derived Earth Fault (50N, 51N) ........................................................................... 35

3.4.1

Instantaneous Derived Earth Fault Protection (50N) ............................................................ 35

3.4.2

Time Delayed Derived Earth Fault Protection (51N) ............................................................. 36

3.5 Current Protection: Measured Earth Fault (50G, 51G) ....................................................................... 36

3.5.1

Instantaneous Measured Earth Fault Protection (50G) ......................................................... 36

3.5.2

Time Delayed Measured Earth Fault Protection (51G) ......................................................... 37

Section 4: Supervision Functions ...................................................................................................................... 38

4.1 Break Capacity Limit (50BCL) .......................................................................................................... 38

4.2 Anti-Backspin (81B) ......................................................................................................................... 39

4.3 Phase Reversal (46 PH REV) .......................................................................................................... 40

4.4 Trip Circuit Supervision (74TCS) ...................................................................................................... 41

4.5 Close Circuit Supervision (74CCS) ................................................................................................... 41

4.6 Circuit Breaker Failure (50BF) .......................................................................................................... 42

4.7 Temperature Inputs (TEMP) ............................................................................................................. 43

7SR105 Rho Description Of Operation

Chapter 1 Page 2 of 57