Siemens SIRIUS 3RW51 Technical Document

Industrial Controls
Soft starters and solid-state
switching devices
SIRIUS 3RW51 Soft Starter
Equipment Manual
09/2020
A5E37108631002A/RS-AC/003
Siemens Industry Online
Support 1
Safety information 2
Description 3
Mounting and Dismantling 4
Wiring 5
Parameter assignment 6
Commissioning 7
Functions 8
Messages & diagnostics 9
Maintenance and servicing 10
Technical speci󹪝cations 11
Dimension drawings 12
Circuit diagrams 13
Example circuits A
Third-party software B

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.
Quali󹪝ed Personnel
The product/system described in this documentation may be operated only by personnel quali󹪝ed for the speci󹪝c
task in accordance with the relevant documentation, in particular its warning notices and safety instructions.
Quali󹪝ed 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 identi󹪝ed 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.
Siemens AG
Smart Infrastructure
Electrical Products
Postfach 10 09 53
93009 Regensburg
GERMANY
A5E37108631002A/RS-AC/003
Ⓟ 09/2020 Subject to change
Copyright © Siemens AG 2018.
All rights reserved

Table of contents
1 Siemens Industry Online Support.......................................................................................................... 9
1.1 Siemens Industry Online Support app................................................................................. 10
1.2 Support Request ................................................................................................................ 11
1.3 Additional documentation ................................................................................................. 11
2 Safety information............................................................................................................................... 13
2.1 ESD Guidelines................................................................................................................... 13
2.2 Five safety rules for working in or on electrical systems....................................................... 14
2.3 Reactive power compensation............................................................................................ 15
2.4 Electromagnetic compatibility (EMC) according to IEC 60947-4-1 ....................................... 15
2.5 Security information .......................................................................................................... 16
2.6 Protection against unauthorized actuation.......................................................................... 16
2.7 Firmware update................................................................................................................ 16
2.8 Recycling and disposal ....................................................................................................... 16
3 Description........................................................................................................................................... 17
3.1 Target group ...................................................................................................................... 17
3.2 Device design .................................................................................................................... 17
3.3 Operating principle ............................................................................................................ 18
3.4 Access options for the 3RW51 soft starter........................................................................... 21
3.5 Operating modes and master control function.................................................................... 22
3.6 Device versions.................................................................................................................. 25
3.7 Areas of application / load types ......................................................................................... 26
3.8 Selection of the soft starter using the Simulation Tool for Soft Starters................................ 27
3.9 Structure of the article number .......................................................................................... 28
3.10 Accessories ........................................................................................................................ 29
3.10.1 Communication modules ................................................................................................... 29
3.10.2 3RW5 HMI ......................................................................................................................... 29
4 Mounting and Dismantling.................................................................................................................. 33
4.1 Installing the 3RW51 soft starter ........................................................................................ 33
4.2 Mounting the optional fan cover ....................................................................................... 33
4.3 Mounting the 3RW51 soft starter on a level surface............................................................ 35
4.4 Mounting the external bypass contactor............................................................................. 36
4.5 Installing / mounting / removing 3RW5 HMI........................................................................ 37
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4.5.1 Installing the 3RW5 HMI Standard in 3RW51 soft starter ..................................................... 37
4.5.2 Removing 3RW5 HMI Standard .......................................................................................... 38
4.5.3 Installing the 3RW5 HMI High Feature in the 3RW51 soft starter ......................................... 39
4.5.4 Removing 3RW5 HMI High Feature .................................................................................... 40
4.5.5 Installing the 3RW5 HMI Standard in the control cabinet door ............................................. 41
4.5.6 Installing the 3RW5 HMI High Feature in the control cabinet door....................................... 45
4.5.7 Installing the 3RW5 HMI Standard on a 󹪞at surface............................................................. 49
4.5.8 Installing the 3RW5 HMI High Feature on a 󹪞at surface....................................................... 50
4.5.9 Cut out the hinged cover for 3RW5 HMI.............................................................................. 52
4.5.10 Replacing the hinged cover of the 3RW51 soft starter ......................................................... 53
5 Wiring .................................................................................................................................................. 55
5.1 Connections ...................................................................................................................... 55
5.1.1 Overview of all connections ............................................................................................... 55
5.1.2 State diagrams of the inputs and outputs ........................................................................... 57
5.2 Connecting the 3RW51 soft starter..................................................................................... 58
5.3 Connecting 3RW51 soft starter to main circuit connection (line side / motor side) ............... 59
5.4 Connecting the external bypass contactor to the 3RW51 soft starter ................................... 61
5.5 Replacing the terminals on size 1/2 devices ........................................................................ 62
5.6 Connecting the control terminals (screw terminals) ............................................................ 64
5.7 Disconnecting the control terminals from the screw-type terminals..................................... 65
5.8 Replacing the control terminals .......................................................................................... 66
5.9 Installing the cover for the control cable duct (optional accessory)...................................... 67
5.10 Removing the cover of the control cable duct (optional accessory)...................................... 68
5.11 Removing the protective board........................................................................................... 69
6 Parameter assignment......................................................................................................................... 71
6.1 Setting elements on the 3RW51 soft starter........................................................................ 71
6.2 Overview of parameters..................................................................................................... 73
6.3 Suggested settings............................................................................................................. 74
6.4 Parameterizing the 3RW51 soft starter ............................................................................... 74
6.5 Setting RESET MODE and Soft Torque ................................................................................. 75
6.6 RESET MODES.................................................................................................................... 77
6.7 Parameterizing output 13 / 14 (Output signal ON or RUN)................................................... 78
6.8 Parameterize the response to bus errors and output 13, 14 (ON /........................................ 79
6.9 Analog output ................................................................................................................... 82
6.10 Parameterize 3RW5 HMI High Feature serially / identically................................................... 82
7 Commissioning .................................................................................................................................... 85
7.1 Commissioning the 3RW51 soft starter............................................................................... 85
7.2 Sealing the 3RW51 soft starter ........................................................................................... 85
7.3 First commissioning of the 3RW5 HMI High Feature ........................................................... 86
Table of contents
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8 Functions ............................................................................................................................................. 89
8.1 Soft starting ...................................................................................................................... 89
8.2 Current limiting function.................................................................................................... 92
8.3 Soft stopping ..................................................................................................................... 94
8.4 Motor protection................................................................................................................ 95
8.4.1 Electronic motor overload protection.................................................................................. 95
8.5 Intrinsic device protection .................................................................................................. 97
8.6 Soft Torque........................................................................................................................ 97
8.7 Functions under "Additional parameters"............................................................................ 99
8.8 Test mode........................................................................................................................ 100
8.9 Test with small load ......................................................................................................... 101
8.10 Response to bus errors / Control via digital input............................................................... 102
8.11 3RW5 HMI Standard ......................................................................................................... 105
8.11.1 Design of the 3RW5 HMI Standard ................................................................................... 105
8.11.2 3RW5 HMI Standard menu ............................................................................................... 106
8.11.3 Setting station address via 3RW5 HMI Standard ................................................................ 108
8.12 3RW5 HMI High Feature .................................................................................................. 109
8.12.1 Monitoring ...................................................................................................................... 109
8.12.1.1 Monitoring the measured values of the 3RW51 soft starter with the 3RW5 HMI High
Feature ........................................................................................................................... 109
8.12.1.2 Graphic display of measured values on the 3RW5 HMI High Feature.................................. 111
8.12.1.3 Monitoring the process image of the 3RW51 soft starter with the 3RW5 HMI High Feature ... 112
8.12.2 Overview......................................................................................................................... 114
8.12.3 Design and operator controls of the 3RW5 HMI High Feature ........................................... 116
8.12.4 Main menu of the 3RW5 HMI High Feature with the 3RW51 soft starter ............................ 118
8.12.5 Parameterizing the 3RW5 HMI High Feature ..................................................................... 121
8.12.6 Parameterizing analog output AQ via the 3RW5 HMI High Feature .................................... 122
8.12.7 De󹪝ning the local access protection (PIN) ......................................................................... 124
8.12.8 Micro SD card .................................................................................................................. 125
9 Messages & diagnostics..................................................................................................................... 129
9.1 Diagnostics options.......................................................................................................... 129
9.2 LED display ...................................................................................................................... 130
9.2.1 Overview of the device LEDs of the 3RW51 soft starter ..................................................... 130
9.2.2 Status and error displays .................................................................................................. 131
9.2.3 STATE / OVERLOAD LED..................................................................................................... 132
9.2.4 Overview of LEDs on 3RW5 HMI Standard ........................................................................ 132
9.2.5 Overview of LEDs on 3RW5 HMI High Feature .................................................................. 133
9.3 Warnings and remedial actions of the 3RW51 soft starter ................................................. 134
9.4 Faults and remedial actions of the 3RW51 soft starter....................................................... 135
9.5 Faults and remedial actions on the 3RW5 HMI High Feature.............................................. 139
9.6 RESET MODES .................................................................................................................. 140
9.7 Diagnostics via the 3RW5 HMI High Feature module ......................................................... 141
Table of contents
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9.7.1 Diagnostics of the 3RW51 soft starter with the 3RW5 HMI High Feature ........................... 141
9.7.2 Diagnostics of communication with the 3RW5 HMI High Feature ...................................... 145
9.7.3 Execute HMI diagnostics with the 3RW5 HMI High Feature................................................ 145
9.7.4 Performing diagnostics of the 3RW5 communication module with the 3RW5 HMI High
Feature............................................................................................................................ 146
9.7.5 Self-test (user-test) .......................................................................................................... 146
9.7.6 Logbooks......................................................................................................................... 149
9.7.7 Save service data to micro SD card ................................................................................... 150
10 Maintenance and servicing ............................................................................................................... 153
10.1 Maintenance and repairs.................................................................................................. 153
10.2 Firmware update.............................................................................................................. 153
10.3 Perform the 󹪝rmware update using micro SD memory card (3RW5 HMI High feature)........ 154
10.4 Restore factory setting ..................................................................................................... 155
10.4.1 Restoring the factory settings via 3RW5 HMI High Feature ................................................ 156
10.4.2 Restoring the factory settings with the Master reset button via 3RW5 HMI High Feature .... 157
10.4.3 Restoring the factory settings with the MODE and RESET / TEST keys................................. 158
10.5 "Device change" function ................................................................................................. 158
10.5.1 Device change with micro SD card on the 3RW5 HMI High Feature.................................... 159
11 Technical speci󹪝cations .................................................................................................................... 161
11.1 Technical data in Siemens Industry Online Support........................................................... 161
12 Dimension drawings.......................................................................................................................... 163
12.1 CAx data.......................................................................................................................... 163
12.2 Drilling pattern for 3RW5 HMI Standard ............................................................................ 163
12.3 Drilling pattern for 3RW5 HMI High Feature ...................................................................... 164
13 Circuit diagrams ................................................................................................................................ 165
13.1 CAx data.......................................................................................................................... 165
A Example circuits ................................................................................................................................ 167
A.1 Main circuit connection.................................................................................................... 167
A.1.1 Feeder assembly, type of coordination 1 fuseless.............................................................. 167
A.1.2 Feeder assembly, type of coordination 1 with fuses .......................................................... 168
A.1.3 Feeder assembly, type of coordination 2........................................................................... 169
A.1.4 Inside-delta circuit ........................................................................................................... 169
A.2 Control circuit connection ................................................................................................ 173
A.2.1 Control by pushbutton ..................................................................................................... 173
A.2.2 Control by switch ............................................................................................................. 175
A.2.3 Switching with the control supply voltage ........................................................................ 177
A.2.4 Control by PLC ................................................................................................................. 179
A.2.5 Actuation of a line contactor ............................................................................................ 181
A.2.6 Wiring for remote RESET................................................................................................... 184
A.2.7 Connecting the evaluation unit to the analog output........................................................ 184
A.2.8 Serial starting of 3 motors with 3RW51 soft starter........................................................... 185
A.3 Special applications ......................................................................................................... 187
A.3.1 Reversing circuit............................................................................................................... 187
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A.3.2 Controlling a motor with a magnetic parking brake........................................................... 187
A.3.3 EMERGENCY STOP shutdown to SIL 1 or PL c with a 3SK1 safety relay................................ 189
A.3.3.1 Wiring of the 3SK1 safety relay SIL 1 with line contactor ................................................... 192
A.3.3.2 Wiring of the 3SK1 safety relay SIL 1 without line contactor .............................................. 193
A.3.4 EMERGENCY STOP shutdown to SIL 3 or PL e with a 3SK1 safety relay ............................... 193
A.3.4.1 Wiring of the 3SK1 safety relay SIL 3 with line contactor ................................................... 197
A.3.4.2 Wiring of the 3SK1 safety relay SIL 3 with line contactor ................................................... 198
A.3.5 Contactor for emergency start.......................................................................................... 198
B Third-party software.......................................................................................................................... 203
B.1 Information about third-party software ............................................................................ 203
Glossary ............................................................................................................................................. 207
Index .................................................................................................................................................. 209
Table of contents
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Table of contents
SIRIUS 3RW51 Soft Starter
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Siemens Industry Online Support 1
Information and service
At Siemens Industry Online Support you can obtain up-to-date information from our global
support database:
• Product support
• Application examples
• Forum
• mySupport
Link: Siemens Industry Online Support (https://support.industry.siemens.com/cs/ww/en/ps)
Product support
You can 󹪝nd information and comprehensive know-how covering all aspects of your product
here:
•FAQs
Answers to frequently asked questions
•Manuals/operating instructions
Read online or download, available as PDF or individually con󹪝gurable.
•Certi󹪝cates
Clearly sorted according to approving authority, type and country.
•Characteristics
For support in planning and con󹪝guring your system.
•Product announcements
The latest information and news concerning our products.
•Downloads
Here you will 󹪝nd updates, service packs, HSPs and much more for your product.
•Application examples
Function blocks, background and system descriptions, performance statements,
demonstration systems, and application examples, clearly explained and represented.
•Technical data
Technical product data for support in planning and implementing your project.
Link: Product support (https://support.industry.siemens.com/cs/de/en)
SIRIUS 3RW51 Soft Starter
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mySupport
The following functions are available in your personal work area "mySupport":
•Support Request
Search for request number, product or subject
•My 󹪝lters
With 󹪝lters, you limit the content of the online support to di󹪜erent focal points.
•My favorites
With favorites you bookmark articles and products that you need frequently.
•My noti󹪝cations
Your personal mailbox for exchanging information and managing your contacts. You can
compile your own individual newsletter in the "Noti󹪝cations" section.
•My products
With product lists you can virtually map your control cabinet, your system or your entire
automation project.
•My documentation
Con󹪝gure your individual documentation from di󹪜erent manuals.
•CAx data
Easy access to CAx data, e.g. 3D models, 2D dimension drawings, EPLAN macros, device
circuit diagrams
•My IBase registrations
Register your Siemens products, systems and software.
1.1 Siemens Industry Online Support app
The Siemens Industry Online Support app provides you access to all the device-speci󹪝c
information available on the Siemens Industry Online Support portal for a particular article
number, such as operating instructions, manuals, data sheets, FAQs etc.
The Siemens Industry Online Support app is available for Android and iOS:
Android iOS
Siemens Industry Online Support
1.1 Siemens Industry Online Support app
SIRIUS 3RW51 Soft Starter
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1.2 Support Request
Use the Support Request online form to send your question directly to Technical Support:
Support Request: Internet (https://support.industry.siemens.com/My/ww/en/requests)
Technical Assistance: Telephone: [phone] (8:00 a.m. - 5:00 p.m. CST)
Fax: [phone]
1.3 Additional documentation
Manuals / online help
At this point, you will 󹪝nd further manuals and online help that may be of interest to you for your
automation system. They are available to download from the Internet free of charge. You can
create your own individual system documentation in mySupport.
• 3RW5 topic page (https://support.industry.siemens.com/cs/ww/en/view/109747404)
• Equipment manual for the 3RW5 soft starter (https://
support.industry.siemens.com/cs/ww/en/ps/16212/man)
• Operating instructions for the 3RW5 soft starter (https://
support.industry.siemens.com/cs/ww/en/ps/16212/man)
• Equipment Manual for the 3RW5 PROFINET communication module (https://
support.industry.siemens.com/cs/ww/en/view/109753754)
• Equipment Manual for the 3RW5 PROFIBUS communication module (https://
support.industry.siemens.com/cs/ww/en/view/109753753)
• SIMATIC PROFINET System Description (https://support.industry.siemens.com/cs/ww/en/
view/19292127)
• Programming manual "From PROFIBUS DP to PROFINET IO" (https://
support.industry.siemens.com/cs/ww/en/view/19289930)
• EMC guide (http://www.siemens.com/emc-guideline)
• IEC guide (http://www.siemens.com/iec60204)
Interesting links
• FAQs for soft starters 3RW5 (https://support.industry.siemens.com/cs/ww/en/ps/16212/faq)
• Manuals in Siemens Industry Online Support (https://support.industry.siemens.com/cs/ww/
en/ps/man)
• FAQs for soft starters 3RW5 (https://support.industry.siemens.com/cs/ww/en/ps/16212/faq)
• Downloads for soft starters 3RW5 (https://support.industry.siemens.com/cs/ww/en/ps/
16212/dl)
Siemens Industry Online Support
1.3 Additional documentation
SIRIUS 3RW51 Soft Starter
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• Product support for STEP 7 (TIA Portal) (https://support.industry.siemens.com/cs/ww/en/ps/
14672)
• Further information on PROFINET (https://www.siemens.com/global/en/home/products/
automation/industrialcommunication/pro󹪝net.html)
Siemens Industry Online Support
1.3 Additional documentation
SIRIUS 3RW51 Soft Starter
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Safety information 2
2.1 ESD Guidelines
ESD
All electronic devices are equipped with large-scale integrated ICs or components. Due to their
design, these electronic elements are highly sensitive to overvoltage, and thus to any
electrostatic discharge.
The acronym ESD has become the established designation for such electrostatic sensitive
components / devices. This is also the international abbreviation for such devices.
ESD devices are identi󹪝ed by the following symbol:
NOTICE
Electrostatic discharge
ESD devices can be destroyed by voltages well below the threshold of human perception. These
static voltages develop when you touch a component or electrical connection of a device
without having drained the static charges present on your body. The damage caused to a device
by overvoltage is usually not immediately evident and is only noticed after an extended period
of operation.
Electrostatic charging
Anyone who is not connected to the electrical potential of their surroundings can be
electrostatically charged.
The diagram below shows the maximum electrostatic voltage which may build up on a person
coming into contact with the materials speci󹪝ed in the diagram. These values correspond to IEC
801-2 speci󹪝cations.
SIRIUS 3RW51 Soft Starter
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9ROWDJHLQN96\QWKHWLFPDWHULDO:RRO$QWLVWDWLFPDWHULDOHJZRRGRUFRQFUHWH5HODWLYHKXPLGLW\LQ
Basic protective measures against electrostatic discharge
• Make sure the grounding is good:
When handling electrostatic sensitive devices, ensure that your body, the workplace and
packaging are grounded. In this way, you can avoid becoming electrostatically charged.
• Avoid direct contact:
As a general rule, only touch electrostatic sensitive devices when if this is unavoidable (for
example, during maintenance work). Handle the devices without touching any chip pins or
PCB traces. In this way, the discharged energy cannot reach or damage sensitive devices.
Discharge your body before taking any necessary measurements on a device. Do so by
touching grounded metallic parts. Use only grounded measuring instruments.
2.2 Five safety rules for working in or on electrical systems
A set of rules, which are summarized as the "󹪝ve safety rules", are de󹪝ned for working in or on
electrical systems as a preventative measure against electrical accidents:
1. Isolate
2. Secure against switching on again
3. Verify that the equipment is not live
4. Ground and short-circuit
5. Erect barriers around or cover adjacent live parts
These 󹪝ve safety rules must be applied in the above order prior to starting work on an electrical
system. After completing the work, proceed in the reverse order.
Safety information
2.2 Five safety rules for working in or on electrical systems
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It is assumed that every electrician is familiar with these rules.
Explanations
1. The isolating distances between live and de-energized parts of the system must vary
according to the operating voltage that is applied.
"Isolate" refers to the all-pole disconnection of live parts.
All-pole disconnection can be achieved, e.g. by.:
- Switching o󹪜 the miniature circuit breaker
- Switching o󹪜 the motor circuit breaker
- Unscrewing fusible links
- Removing LV HRC fuses
2. The feeder must be locked against inadvertent reconnection to ensure that it remains
isolated for the duration of the work. This can be achieved, for instance, by locking the motor
and system circuit breakers in the OFF position or by unscrewing the fuses and using lockable
elements to prevent them from being reinserted.
3. The de-energized state of the equipment should be veri󹪝ed using suitable test equipment,
e.g. a two-pole voltmeter. Single-pole test pins are not suitable for this purpose. The absence
of power must be established for all poles, phase to phase, and phase to N/PE.
4. Grounding and short-circuiting are only mandatory if the system has a nominal voltage
greater than 1 kV. In this case, the system should always be grounded 󹪝rst and then
connected to the live parts to be short-circuited.
5. These parts should be covered, or barriers erected around them, to avoid accidental contact
during the work with adjacent parts that are still live.
2.3 Reactive power compensation
Capacitors for improving the power factor (reactive power compensation)
Capacitors may not be connected to the output terminals of the 3RW51 soft starter. Connecting
capacitors to the output terminals will damage the 3RW51 soft starter.
Active 󹪝lters, e.g. for reactive power compensation, must not be operated parallel to the motor
control device.
If capacitors are to be used to correct the power factor (actively or passively), they must be
connected on the line side of the device. They must not actively control the power factor during
the starting and coasting down phases. If a contactor disconnector or main contactor are used
together with the electronic 3RW51 soft starter, the capacitors must be disconnected from the
3RW51 soft starter when the contactor is open.
2.4 Electromagnetic compatibility (EMC) according to IEC 60947-4-1
This product is designed for Environment A. It may produce radio interference in domestic
environments, in which case the user may be required to take adequate mitigation measures.
Safety information
2.4 Electromagnetic compatibility (EMC) according to IEC 60947-4-1
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2.5 Security information
Siemens provides products and solutions with industrial security functions that support the
secure operation of plants, systems, machines, and networks.
In order to protect plants, systems, machines and networks against cyber threats, it is necessary
to implement – and continuously maintain – a holistic, state-of-the-art industrial security
concept. Siemens’ products and solutions form one element of such a concept.
Customers are responsible for preventing unauthorized access to their plants, systems,
machines and networks. These systems, machines and components should only be connected
to the enterprise network or the Internet if and only to the extent necessary and with appropriate
security measures (󹪝rewalls and/or network segmentation) in place.
You can 󹪝nd more information on protective measures in the area of industrial security by
visiting:
https://www.siemens.com/industrialsecurity.
Siemens’ products and solutions undergo continuous development to make them more secure.
Siemens strongly recommends performing product updates as soon as they are available and
using only the latest product versions. Use of product versions that are no longer supported, and
failure to apply latest updates may increase customer’s exposure to cyber threats.
To stay informed about product updates, subscribe to the Siemens Industrial Security RSS Feed
under
https://www.siemens.com/industrialsecurity.
2.6 Protection against unauthorized actuation
Protect freely accessible operator controls on your machine / system against unauthorized
actuation if this could result in a risk or danger. Take suitable action in this regard, for example,
a lockable key-operated switch.
2.7 Firmware update
To be able to use 3RW51 soft starters without any problem and with their full range of
functions, ensure that all components have the latest 󹪝rmware (Page 153):
• 3RW51 soft starter
• 3RW5 HMI High Feature (accessory)
• 3RW5 communication module (accessory)
You will 󹪝nd current downloads and a history of the versions with new features on the
3RW5 topic page (https://support.industry.siemens.com/cs/ww/en/view/109747404).
2.8 Recycling and disposal
For environmentally friendly recycling and disposal of your old device, please contact a company
certi󹪝ed for the disposal of old electrical and/or electronic devices and dispose of the device in
accordance with the regulations in your country.
Safety information
2.8 Recycling and disposal
SIRIUS 3RW51 Soft Starter
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Description 3
3.1 Target group
The manual is intended for everyone involved in the following tasks:
• Planning and con󹪝guring systems
• Installation
• Commissioning
• Service and maintenance
Requirements for use of 3RW5 soft starters
Basic knowledge of the following areas:
• General electrical engineering
• Drive technology
• Automation technology
• Handling the automation system and the software used
3.2 Device design
WARNING
Fire hazard. Short-circuit hazard. Property damage. Can cause death or serious injury.
The soft starter is supplied with a protective cover to prevent foreign parts from entering the
device during installation. Remove the protective cover before commissioning.
SIRIUS 3RW51 Soft Starter
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①Main circuit connection (mains supply and external bypass)
②Slot for 3RW5 HMI Standard (accessory) or 3RW5 HMI High Feature (accessory)
③Interface for 3RW5 HMI Standard (accessory) or 3RW5 HMI High Feature (accessory)
④Setting elements for parameter assignment
⑤MODE key
⑥Slot for 3RW5 communication module (accessory)
⑦Connectible conductor cross sections
You will also 󹪝nd the conductor cross-sections that can be connected in the Technical data
(Page 161).
⑧Scale for the setting element Ie
You will also 󹪝nd the applicable scale in the Technical data (Page 161).
⑨Diagnostics LEDs and RESET / TEST key
⑩Eye for lead seal
⑪Main circuit connection (motor)
⑫Control terminals (inputs / outputs)
⑬Control cable duct with cover
3.3 Operating principle
Soft starters are used to start three-phase induction motors with reduced torque and reduced
starting current.
Description
3.3 Operating principle
SIRIUS 3RW51 Soft Starter
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The 3RW51 soft starter starts the motor as soon as the switch-on command is issued (t1). During
the ramp-up time (t1 to t3), the current is conducted via power semiconductors (switching
elements) which starts up the motor smoothly.
The 3RW51 soft starter features internal ramp-up detection. The following operation occurs
when the motor reaches its rated operating speed before the ramp-up time has elapsed:
• The motor voltage is immediately increased to 100 % of the line voltage (t2)
• The external bypass contactor close
• The power semiconductors are bypassed and the soft starter is in bypass operation.
Cancelling the switch-on command activates the stopping mode and the motor is shut down.
The power semiconductors also ensure that the motor coasts down smoothly to a stop. As long
as the stopping time is active (t4 to t5), the power is still supplied to the motor. It may take longer
for the motor to actually coast down to standstill (t6).
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①Speed t5End of the set stopping time (t5-t4)
②Voltage t6Motor at standstill
t1Motor start-up with set starting voltage USUSSet starting voltage
t2Rated speed ne achieved UeRated operational voltage
t3End of the set ramp-up time (t3-t1) neRated operating speed of the motor
t4Switch-on command is cancelled, motor is
switched o󹪜
Functions
Note the information in chapter Firmware update (Page 153).
•Soft starting with parameterizable starting voltage and ramp up time for a smooth starting
of the drive
•Soft stopping with parameterizable stopping time for a smooth run-down of the drive
• Parameterizable current limit for avoiding current peaks
•Soft torque for smooth ramp-up and run-down (avoiding torque peaks by means of torque
limitation)
Description
3.3 Operating principle
SIRIUS 3RW51 Soft Starter
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•Integrated electronic motor overload protection with adjustable trip class (Class 10A, 10E,
20E, Class OFF)
•Intrinsic device protection protects the 3RW51 soft starter against overload
•Ramp-up detection
• Extended operating and diagnostic functions is provided by the optional 3RW5 HMI
Standard or 3RW5 HMI High Feature
• Connection to the motor in standard (inline) circuit or in inside-delta circuit
• Adjustable RESET MODE (Manual RESET, Remote RESET, Auto RESET) for the functions of
motor protection
•Analog output for displaying a set measured value
• Optional 3RW5 communication module for integration into bus systems
• Firmware updates upgrade the 󹪝rmware of the respective device
Additional information
You will 󹪝nd an overview of all of the functions of the 3RW5 soft starter in the Catalog IC 10
(https://support.industry.siemens.com/cs/ww/en/view/109747945).
You will 󹪝nd further details of the functions in chapter Functions (Page 89).
Description
3.3 Operating principle
SIRIUS 3RW51 Soft Starter
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