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
