Siemens SIRIUS 3RU2 User manual

GerätehandbuchManual
Industrial Controls
Protection Devices
SIRIUS Innovations - Thermal Overload Relays SIRIUS 3RU2 / Solid-State Overload Relays SIRIUS 3RB3
Edition
Answers for industry.
09/2014

SIRIUS Innovations - SIRIUS 3RU2
thermal overload relays / SIRIUS 3RB3
solid-state overload relays
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Industrial Controls
Protection devices
SIRIUS Innovations - SIRIUS 3RU2
thermal overload relays / SIRIUS
3RB3 solid-state overload relays
Manual
09/2014
A5E03656507420A/RS-AA/002
Introduction
1
Standards
2
Product description
3
Product combinations
4
Functions
5
Configuration
6
Mounting
7
Connection
8
Operation
9
Accessories
10
Technical data
11
Circuit diagrams
12
Types of coordination
A
References
B
Dimension drawings
(dimensions in mm)
C
Correction sheet
D

Siemens AG
Industry Sector
Postfach 48 48
90026 NÜRNBERG
GERMANY
3ZX1012-0RU20-5AC1
Ⓟ09/2014 Subject to change
Copyright © Siemens AG 2011.
All rights reserved
Legal information
Warning notice system
This manual contains notices you have to observe in order to ensure your personal safety, as well as to prevent
damage to property. The notices referring to your personal safety are highlighted in the manual by a safety alert
symbol, notices referring only to property damage have no safety alert symbol. These notices shown below are
graded according to the degree of danger.
DANGER
indicates that death or severe personal injury
will
result if proper precautions are not taken.
WARNING
indicates that death or severe personal injury
may
result if proper precautions are not taken.
CAUTION
indicates that minor personal injury can result if proper precautions are not taken.
NOTICE
indicates that property damage can result if proper precautions are not taken.
If more than one degree of danger is present, the warning notice representing the highest degree of danger will
be used. A notice warning of injury to persons with a safety alert symbol may also include a warning relating to
property damage.
Qualified Personnel
The product/system described in this documentation may be operated only by
personnel qualified
for the specific
task in accordance with the relevant documentation, in particular its warning notices and safety instructions.
Qualified personnel are those who, based on their training and experience, are capable of identifying risks and
avoiding potential hazards when working with these products/systems.
Proper use of Siemens products
Note the following:
WARNING
Siemens products may only be used for the applications described in the catalog and in the relevant technical
documentation. If products and components from other manufacturers are used, these must be recommended
or approved by Siemens. Proper transport, storage, installation, assembly, commissioning, operation and
maintenance are required to ensure that the products operate safely and without any problems. The permissible
ambient conditions must be complied with. The information in the relevant documentation must be observed.
Trademarks
All names identified by ® are registered trademarks of Siemens AG. The remaining trademarks in this publication
may be trademarks whose use by third parties for their own purposes could violate the rights of the owner.
Disclaimer of Liability
We have reviewed the contents of this publication to ensure consistency with the hardware and software
described. Since variance cannot be precluded entirely, we cannot guarantee full consistency. However, the
information in this publication is reviewed regularly and any necessary corrections are included in subsequent
editions.

SIRIUS Innovations - SIRIUS 3RU2 thermal overload relays / SIRIUS 3RB3 solid-state overload relays
Manual, 09/2014, A5E03656507420A/RS-AA/002 5
Table of contents
1 Introduction............................................................................................................................................. 9
1.1 Responsibility of the user for system configuration and functionality .......................................9
1.2 Service&Support .....................................................................................................................11
1.3 DataMatrix code......................................................................................................................14
2 Standards ............................................................................................................................................. 17
2.1 Standards................................................................................................................................17
3 Product description ............................................................................................................................... 19
3.1 Introduction .............................................................................................................................19
3.2 Versions ..................................................................................................................................21
3.3 Applications.............................................................................................................................22
3.4 3RU21 thermal overload relays ..............................................................................................24
3.5 3RB30 solid-state overload relays ..........................................................................................27
3.6 3RB31 solid-state overload relays ..........................................................................................30
4 Product combinations............................................................................................................................ 35
5 Functions .............................................................................................................................................. 37
5.1 Protection against overload, phase failure, and phase asymmetry........................................37
5.1.1 Functional principle .................................................................................................................37
5.1.2 Inverse-time delayed overload release...................................................................................38
5.1.3 Tripping classes ......................................................................................................................38
5.1.4 Tripping characteristics ...........................................................................................................39
5.2 Ground fault protection in the case of the 3RB31...................................................................43
5.3 Auxiliary contacts ....................................................................................................................44
5.4 Indication of the operating state..............................................................................................45
5.5 Self-monitoring (3RB30/3RB31 only)......................................................................................45
5.6 Additional functions.................................................................................................................46
6 Configuration ........................................................................................................................................ 49
6.1 SIRIUS Innovations system configurator ................................................................................49
6.2 Overload relays in motor feeders............................................................................................50
6.2.1 Motor protection with overload relay.......................................................................................50
6.2.2 Overview of combinable 3RT2 contactors ..............................................................................51
6.2.3 Normal and heavy-duty starting..............................................................................................52
6.2.4 Contactor assembly for star-delta (wye-delta) start................................................................53
6.2.5 Operation with frequency converters ......................................................................................54

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SIRIUS Innovations - SIRIUS 3RU2 thermal overload relays / SIRIUS 3RB3 solid-state overload relays
6Manual, 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

Table of contents
SIRIUS Innovations - SIRIUS 3RU2 thermal overload relays / SIRIUS 3RB3 solid-state overload relays
Manual, 09/2014, A5E03656507420A/RS-AA/002 7
10.6 Covers for ring cable lug connections.....................................................................................99
10.6.1 Description ..............................................................................................................................99
11 Technical data .................................................................................................................................... 101
11.1 Product data sheet................................................................................................................101
11.2 Performance features ...........................................................................................................104
11.2.1 General data .........................................................................................................................104
11.2.2 Protection functions - overview.............................................................................................105
11.2.3 Equipment.............................................................................................................................106
11.2.4 Configuration of load feeders................................................................................................106
11.2.5 Features of overload relays ..................................................................................................107
11.3 3RU21 thermal overload relays ............................................................................................108
11.3.1 3RU2116/3RU2126 thermal overload relays........................................................................108
11.3.1.1 General technical data ..........................................................................................................108
11.3.1.2 Main circuit............................................................................................................................110
11.3.1.3 Main circuit terminals ............................................................................................................111
11.3.1.4 Auxiliary circuit ......................................................................................................................113
11.3.1.5 Auxiliary circuit connections..................................................................................................114
11.3.2 3RU2136 thermal overload relay ..........................................................................................116
11.3.2.1 General technical data ..........................................................................................................116
11.3.2.2 Main circuit............................................................................................................................118
11.3.2.3 Main circuit terminals ............................................................................................................118
11.3.2.4 Auxiliary circuit ......................................................................................................................119
11.3.2.5 Auxiliary circuit connections..................................................................................................120
11.3.2.6 Protection function ................................................................................................................120
11.3.2.7 Safety ....................................................................................................................................120
11.3.2.8 Mounting/fixing/dimensions ..................................................................................................121
11.3.2.9 UL/CSA rated data................................................................................................................121
11.3.2.10 Rated operating current, short-circuit protection, tripping class, and active power loss ......122
11.4 3RB30/3RB31 solid-state overload relays ............................................................................123
11.4.1 3RB301/3RB302/3RB311/3RB312 solid-state overload relays............................................123
11.4.1.1 General technical data ..........................................................................................................123
11.4.1.2 Main circuit............................................................................................................................126
11.4.1.3 Conductor cross-sections main circuit ..................................................................................127
11.4.1.4 Auxiliary circuit ......................................................................................................................128
11.4.1.5 Conductor cross sections, auxiliary circuit............................................................................130
11.4.2 3RB303/3RB313 solid-state overload relays........................................................................131
11.4.2.1 General technical data ..........................................................................................................131
11.4.2.2 Main circuit............................................................................................................................133
11.4.2.3 Main circuit terminals ............................................................................................................134
11.4.2.4 Auxiliary circuit ......................................................................................................................135
11.4.2.5 Auxiliary circuit connections..................................................................................................136
11.4.2.6 Protection function ................................................................................................................137
11.4.2.7 Mounting/fixing/dimensions ..................................................................................................138
11.4.2.8 UL/CSA rated data................................................................................................................139
11.4.2.9 Rated operating current and active power loss ....................................................................140

Table of contents
SIRIUS Innovations - SIRIUS 3RU2 thermal overload relays / SIRIUS 3RB3 solid-state overload relays
8Manual, 09/2014, A5E03656507420A/RS-AA/002
12 Circuit diagrams...................................................................................................................................141
A Types of coordination...........................................................................................................................145
B References ..........................................................................................................................................147
B.1 References........................................................................................................................... 147
B.2 SIRIUS Innovations manuals ............................................................................................... 148
B.3 More information .................................................................................................................. 150
C Dimension drawings (dimensions in mm) .............................................................................................151
C.1 Dimension drawings for 3RU21 thermal overload relays .................................................... 151
C.2 Dimension drawings for 3RB30/3RB31 solid-state overload relays .................................... 157
C.3 3RT2 contactors drilling plan ............................................................................................... 164
C.4 Dimension drawings and drilling plan for 3RU29.6 stand-alone assembly supports........... 166
D Correction sheet ..................................................................................................................................171
Index ...................................................................................................................................................173

SIRIUS Innovations - SIRIUS 3RU2 thermal overload relays / SIRIUS 3RB3 solid-state overload relays
Manual, 09/2014, A5E03656507420A/RS-AA/002 9
Introduction
1
1.1
Responsibility of the user for system configuration and functionality
3RU21 thermal overload relays have been designed to provide current-dependent protection
for loads with normal starting against impermissibly high temperature rises due to overload,
phase asymmetry or phase failure.
3RB30 / 3RB31 solid-state overload relays with internal power supply have been designed to
provide current-dependent protection for loads with normal starting and heavy starting
against impermissibly high temperature rises due to overload, phase asymmetry or phase
failure.
Siemens AG, its regional offices, and associated companies (hereinafter referred to as
"Siemens") cannot guarantee all the properties of an overall installation or machine that has
not been designed by Siemens.
Nor can Siemens assume liability for recommendations that appear or are implied in the
following description. No new guarantee, warranty, or liability claims beyond the scope of the
Siemens general terms of supply are to be derived or inferred from the following description.
Purpose of the manual
This manual describes the 3RU2/3RB3 overload relays and provides the following
information:
●Information for integrating the overload relays into the system environment.
●Information on necessary hardware components.
●Information on installing, connecting and operating the overload relays.
●Technical information such as dimension drawings and unit wiring diagrams.
The information in this manual enables you to configure and commission the overload relays.

Introduction
1.1 Responsibility of the user for system configuration and functionality
SIRIUS Innovations - SIRIUS 3RU2 thermal overload relays / SIRIUS 3RB3 solid-state overload relays
10 Manual, 09/2014, A5E03656507420A/RS-AA/002
Advantages through energy efficiency
Siemens offers you a unique portfolio for efficient energy management in industry – a
process that serves to optimally shape your energy requirement. Operational energy
management is subdivided into three phases:
●Identifying
●Evaluating
●Realizing
Siemens supports you with suitable hardware and software solutions in every phase of a
project.
More information can be found on the Internet
(http://www.automation.siemens.com/mcms/industrial-controls/en/energy-efficiency).
The 3RB30/3RB31 electronic overload relays make the following contribution to energy
efficiency in an overall installation:
●Reduced intrinsic power loss
●Reduced control cabinet heat development
●Smaller control cabinet air conditioning units required
Figure 1-1 Overview of the energy management process
Required basic knowledge
To understand these operating instructions you should have a general knowledge of
automation engineering and low-voltage switchgear.
Scope of the manual
The manual is valid for these overload relays. It contains a description of the devices that is
valid at the time of publication.

Introduction
1.2 Service&Support
SIRIUS Innovations - SIRIUS 3RU2 thermal overload relays / SIRIUS 3RB3 solid-state overload relays
Manual, 09/2014, A5E03656507420A/RS-AA/002 11
1.2
Service&Support
Online Support
The Online Support in the Service&Support portal is an extensive information system for all
questions relating to Siemens products and solutions. This service enables direct and central
access to in-depth information concerning the products, systems and applications for
industry and to a large number of programming, configuration and application examples. Its
content is available via a mobile app.
The Technical Forum of the Online Support provides the opportunity for users to swap
information. Support Request allows contact to be established with Siemens experts in
Technical Support.
Siemens Industry Online Support ensures that users in industry are always kept up-to-date
with news, software updates and announcements by means of newsletters and Twitter.
Links:
Service&Support Portal (http://support.automation.siemens.com), Online Support
(http://support.automation.siemens.com/WW/view/en/16605022)
Product Support
Are you looking for product information such as technical data, updates or FAQs? Here, the
"Product Support" section of the Service & Support Portal offers an extensive collection of all
information about the Siemens Industry Automation and Drive Technologies products and
solutions:
●Answers to frequently asked questions (FAQs)
●Updates/upgrades, service packs and support tools for downloading
●Manuals and operating instructions
●Technical data/CAx data
●Approvals and certificates
●Test certificates and characteristic curves
All Product Support information is at your disposal free of charge and around the clock, and
you always get the current version.
Link:
Product Support (http://support.automation.siemens.com/WW/view/en/4000024)

Introduction
1.2 Service&Support
SIRIUS Innovations - SIRIUS 3RU2 thermal overload relays / SIRIUS 3RB3 solid-state overload relays
12 Manual, 09/2014, A5E03656507420A/RS-AA/002
CAx data
The CAx Download Manager provides you with a simple means of gaining access to up-to-
date product data for your CAx or CAe system.
You configure your own download package with just a few clicks. You can choose from the
following information for products
●Product images
●2D dimensional drawings
●3D models
●Internal circuit diagrams
●EPLAN macro files
●Manuals
●Characteristics
●Operating instructions
●Certificates
●Product master data
Link:
CAx Download Manager
(http://support.automation.siemens.com/WW/view/en/42455541)
Applications & Tools
Applications & Tools supports you with various tools and examples when it comes to solving
your automation tasks. Solutions are presented in interaction with several components in the
system, without focusing on individual products.
●Application examples
●Function blocks & tools
●Background and system descriptions
●Performance statements
●Demonstration systems/videos
Link:
Applications & Tools (http://support.automation.siemens.com/WW/view/en/20208582)

Introduction
1.2 Service&Support
SIRIUS Innovations - SIRIUS 3RU2 thermal overload relays / SIRIUS 3RB3 solid-state overload relays
Manual, 09/2014, A5E03656507420A/RS-AA/002 13
My Documentation Manager
My Documentation Manager enables you to compile your own documentation from our
standard documents (manuals), which are located in the Product Support section. Under
mySupport, you have the opportunity to create and manage you own compilations in a
structure of their own.
Link:
MyDocumentationManager (http://support.automation.siemens.com/WW/view/en/38715968)
Reference
You can find further information on structure and navigation in Online Support here
(http://support.automation.siemens.com/WW/view/en/11774658).
Further documentation
To install and connect the overload relays, you require the operating instructions of the
overload relays used.
You can find a list of operating instructions and an overview of the manuals pertaining to
SIRIUS Innovations in the appendix "References (Page 147)".

Introduction
1.3 DataMatrix code
SIRIUS Innovations - SIRIUS 3RU2 thermal overload relays / SIRIUS 3RB3 solid-state overload relays
14 Manual, 09/2014, A5E03656507420A/RS-AA/002
1.3
DataMatrix code
A DataMatrix code has been lasered onto 3RB3 solid-state overload relay devices under the
label (size S2 only).
The DataMatrix codes are standardized in ISO/IEC 16022. The DataMatrix codes on
Siemens devices use ECC200 coding for powerful error correction.
The following device information is encoded in the DataMatrix codes as a bit stream:
●Article number
●Serial number
●If applicable, MAC address
This information is stored in the following format in the DataMatrix code:
1P Article number + S Location / Date Serial number
Data
identifier
User content Separator User content Separator User
content
User content
Note
The information content is displayed without spaces.
This machine-readable information simplifies and accelerates handling of the respective
devices.
As well as fast access to the serial numbers of the respective devices for unique
identification, the DataMatrix codes simplify communication with Siemens Technical Support.

Introduction
1.3 DataMatrix code
SIRIUS Innovations - SIRIUS 3RU2 thermal overload relays / SIRIUS 3RB3 solid-state overload relays
Manual, 09/2014, A5E03656507420A/RS-AA/002 15
SIEMENS Industry Support App
DataMatrix codes primarily enable extremely fast and convenient access to all device-
specific information relating to an article number in the SIEMENS Service&Support Portal,
such as operating instructions, manuals, data sheets, FAQs, etc.
We provide the SIEMENS Industry Support app free for this purpose and it can be used on
most commercially available smartphones and tablets.
The SIEMENS Industry Support app is available for iOS and Android-based devices and can
be accessed via the following links:
Link for Android Link for iOS

Introduction
1.3 DataMatrix code
SIRIUS Innovations - SIRIUS 3RU2 thermal overload relays / SIRIUS 3RB3 solid-state overload relays
16 Manual, 09/2014, A5E03656507420A/RS-AA/002
Recycling and disposal
These devices can be recycled thanks to their low pollutant content. For environmentally-
friendly recycling and disposal of your electronic waste, please contact a company certified
for the disposal of electronic waste.
Up-to-the-minute information
You can obtain further assistance by calling the following numbers:
Technical Assistance:
Telephone: [phone] (8 a.m. to 5 p.m. CET)
Fax: [phone]
or on the Internet at:
E-mail: (mailto:[e-mail])
Internet: (http://www.siemens.com/sirius/technical-assistance)
Correction sheet
A correction sheet is included at the end of the manual. Please use it to record your
suggestions for improvements, additions and corrections, and return the sheet to us. This will
help us to improve the next edition of the manual.

SIRIUS Innovations - SIRIUS 3RU2 thermal overload relays / SIRIUS 3RB3 solid-state overload relays
Manual, 09/2014, A5E03656507420A/RS-AA/002 17
Standards
2
2.1
Standards
Applicable standards
3RU21 thermal overload relays and 3RB30/3RB31 solid-state overload relays meet the
requirements of the following standards:
Table 2- 1 Standards
Device standards •IEC/EN 60947-1
•IEC/EN 60947-4-1
•IEC/EN 60947-5-1
•UL 508
•UL 60947-4-1
•CSA C 22.2
EMC standard 3RB30°/ 3RB31 electronic overload relays additionally fulfill the EMC
standards specified in IEC 60947-4-1.
Resistance to
extreme climates
The overload relays are climate-proof according to IEC 60721-3.
Touch protection Degree of protection according to IEC 60529: IP20
You can find more information about the touch protection of 3RU21 thermal overload relays
and 3RB3 solid-state relays in the Chapter "Connection (Page 65)".
Reference
Other standards that the 3RU21 and 3RB30 / 3RB31 overload relays conform to are listed in
the Chapter "Technical data (Page 101)". SIRIUS components have been approved by a
whole range of bodies for various sectors (shipbuilding, etc.). An up-to-date list of approvals
is provided in Chapter 16 of the Siemens catalog IC 10 - "SIRIUS Industrial Controls". You
will find more information and an option to download certificates on the internet
(http://www.siemens.com/automation/service&support).

Standards
2.1 Standards
SIRIUS Innovations - SIRIUS 3RU2 thermal overload relays / SIRIUS 3RB3 solid-state overload relays
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SIRIUS Innovations - SIRIUS 3RU2 thermal overload relays / SIRIUS 3RB3 solid-state overload relays
Manual, 09/2014, A5E03656507420A/RS-AA/002 19
Product description
3
3.1
Introduction
3RU21 thermal overload relays
3RU21 thermal overload relays up to 80 A have been designed to provide current-dependent
protection for loads with normal starting against impermissibly high temperature rises due to
overload, phase asymmetry or phase failure.
An overload or phase failure results in an increase of the motor current beyond the set rated
motor current. Via heating elements, this current rise increasingly heats up the bimetal strips
located inside the device. The deflection of these bimetal strips eventually activates the
auxiliary contacts via a release mechanism. The contacts then disconnect the load via a
contactor. (The contactor function is not an integral component of the overload relay).
3RB30/3RB31 solid-state overload relays
3RB30 / 3RB31 solid-state overload relays up to 80 A with internal power supply have been
designed to provide current-dependent protection for loads with normal starting and heavy
starting against impermissibly high temperature rises due to overload, phase asymmetry or
phase failure.
An overload, phase asymmetry or a phase failure results in an increase of the motor current
beyond the set rated motor current.
This current rise is detected by the current transformers integrated in the devices and
evaluated by corresponding solid-state circuits which then supply a pulse to the auxiliary
contacts. The contacts then disconnect the load via a contactor. (The contactor function is
not an integral component of the overload relay).
In addition to current-dependent protection for loads against impermissibly high temperature
rise caused by overload, phase asymmetry, and phase failure, 3RB31 solid-state overload
relays feature internal ground-fault detection (not possible in conjunction with contactor
assemblies for star-delta (wye-delta) start). This provides protection of loads against high-
impedance faults to ground caused by damaged insulation, moisture, condensation, etc.

Product description
3.1 Introduction
SIRIUS Innovations - SIRIUS 3RU2 thermal overload relays / SIRIUS 3RB3 solid-state overload relays
20 Manual, 09/2014, A5E03656507420A/RS-AA/002
System integration
The overload relays have been matched to the contactors in the 3RT2 series both electrically
and mechanically and can be integrated in the feeder by means of direct mounting.
3RU2 thermal overload relays and 3RB30 and 3RB31 solid-state overload relays are
available in three sizes, S00, S0 and S2.
Connection systems
The overload relays are available with the following connection system options:
●Screw-type connection system
●Spring-loaded connection system (size S2 auxiliary circuit only)
●Ring cable lug connection technology (3RU21 only, in size S00 and S0)
3RB3 solid-state overload relays are available in size S2 also in through-hole technology
with straight-through transformer.
Accessories
The accessories have been tailored to the overload relays; they can be mounted easily and
without the need for tools.