Siemens SIRIUS 3RU2 - Page 6

Table of contents
SIRIUS Innovations - SIRIUS 3RU2 thermal overload relays / SIRIUS 3RB3 solid-state overload relays
6 Manual, 09/2014, A5E03656507420A/RS-AA/002
6.3 Short-circuit protection ........................................................................................................... 55
6.4 Protecting explosion-protected motors .................................................................................. 56
6.5 Application environment ......................................................................................................... 57
7 Mounting ............................................................................................................................................... 59
7.1 Mounting options .................................................................................................................... 59
7.2 Minimum clearances and mounting position .......................................................................... 59
7.3 Mounting/Disassembly ........................................................................................................... 60
8 Connection ........................................................................................................................................... 65
8.1 Connection ............................................................................................................................. 65
8.2 Connection of 3RU21 overload relay ..................................................................................... 66
8.3 Connection of 3RB30/3RB31 overload relays ....................................................................... 66
8.4 Connection cross-sections ..................................................................................................... 67
8.4.1 Conductor cross-sections for screw-type connection systems .............................................. 67
8.4.2 Conductor cross-sections for spring-loaded connection systems ......................................... 70
8.4.3 Conductor cross-sections for ring cable lug connection system ............................................ 72
9 Operation .............................................................................................................................................. 75
9.1 Setting the current .................................................................................................................. 75
9.2 Setting the tripping class/ground-fault detection (3RB31) ..................................................... 76
9.3 RESET after release .............................................................................................................. 77
9.4 TEST function ........................................................................................................................ 80
9.5 Response of the auxiliary contacts ........................................................................................ 82
10 Accessories .......................................................................................................................................... 83
10.1 Accessories ............................................................................................................................ 83
10.2 Terminal support for stand-alone assembly ........................................................................... 84
10.2.1 Description ............................................................................................................................. 84
10.2.2 Mounting/Disassembly ........................................................................................................... 84
10.3 Mechanical remote RESET .................................................................................................... 90
10.3.1 Release slide .......................................................................................................................... 90
10.3.1.1 Description ............................................................................................................................. 90
10.3.1.2 Mounting/Disassembly ........................................................................................................... 91
10.3.2 Cable release ......................................................................................................................... 92
10.3.2.1 Description ............................................................................................................................. 92
10.3.2.2 Mounting/Disassembly ........................................................................................................... 93
10.4 Module for electrical remote RESET (3RU21 only) ............................................................... 95
10.4.1 Description ............................................................................................................................. 95
10.4.2 Connecting the remote RESET .............................................................................................. 95
10.4.3 Mounting/Disassembly ........................................................................................................... 96
10.5 Sealable cover ....................................................................................................................... 97
10.5.1 Description ............................................................................................................................. 97
10.5.2 Mounting ................................................................................................................................ 98