Siemens SIRIUS 3RW55 Technical Document

Industrial Controls
Soft starters and solid-state
switching devices
SIRIUS 3RW55 and 3RW55 Failsafe
Soft Starters
Equipment Manual
02/2022
A5E35630887002A/RS-AF/006
Siemens Industry Online
Support 1
Safety information 2
Description 3
Mounting and dismantling 4
Connecting 5
Parameter assignment 6
Commissioning 7
Functions 8
Messages and diagnostics 9
Maintenance and service 10
Technical speci󹪝cations 11
Dimension drawings 12
Circuit diagrams 13
Example circuits A

Legal information
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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
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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.
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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.
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Smart Infrastructure
Electrical Products
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A5E35630887002A/RS-AF/006
Ⓟ 04/2022 Subject to change
Copyright © Siemens AG 2018.
All rights reserved

Table of contents
1 Siemens Industry Online Support.......................................................................................................... 9
1.1 Support Request ................................................................................................................ 11
1.2 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 60947-4-2 ....................................... 15
2.5 Security information .......................................................................................................... 16
2.6 ATEX / IECEx....................................................................................................................... 16
2.6.1 Use in Class I and Class II Hazardous Locations.................................................................... 16
2.6.2 ATEX/IECEx-certi󹪝ed motor overload protection .................................................................. 16
2.7 Failsafe .............................................................................................................................. 20
2.8 Protection against unauthorized actuation.......................................................................... 22
2.9 Firmware update................................................................................................................ 22
2.10 Recycling and disposal ....................................................................................................... 22
3 Description........................................................................................................................................... 23
3.1 History............................................................................................................................... 23
3.2 Hardware con󹪝guration ..................................................................................................... 24
3.3 Operating principle ............................................................................................................ 25
3.4 3RW5 HMI High Feature..................................................................................................... 28
3.5 Options for accessing the 3RW55 and 3RW55 Failsafe soft starters...................................... 30
3.6 Operating modes and master control function.................................................................... 32
3.6.1 Operating modes............................................................................................................... 32
3.6.2 Sets the operating mode.................................................................................................... 35
3.7 Device versions.................................................................................................................. 39
3.8 Areas of application and load types .................................................................................... 43
3.9 Selection of the soft starter using the Simulation Tool for Soft Starters................................ 44
3.10 Structure of the article number .......................................................................................... 44
3.11 Accessories ........................................................................................................................ 49
3.11.1 Accessories for 3RW55 and 3RW55 Failsafe soft starters...................................................... 49
3.11.2 3RW5 communication module ........................................................................................... 51
3.11.3 SIRIUS Soft Starter ES (TIA Portal) ....................................................................................... 51
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4 Mounting and dismantling .................................................................................................................. 55
4.1 Mounting 3RW55 and 3RW55 Failsafe soft starters ............................................................. 55
4.2 Mounting the fan cover...................................................................................................... 55
4.3 Mount the 3RW55 and 3RW55 Failsafe soft starters on a level surface................................. 56
4.4 Installing, mounting and removing the 3RW5 HMI High Feature ......................................... 60
4.4.1 Removing the 3RW5 HMI High Feature ............................................................................... 60
4.4.2 Installing the 3RW5 HMI High Feature in the 3RW55 or 3RW55 Failsafe soft starter ............. 61
4.4.3 Installing the High Feature 3RW5 HMI on a 󹪞at surface....................................................... 62
4.4.4 Installing the 3RW5 HMI High Feature in the control cabinet door....................................... 64
4.4.5 Replacing the hinged cover of the 3RW55 or 3RW55 Failsafe soft starter ............................. 68
5 Connecting .......................................................................................................................................... 71
5.1 Overview of all connections of the 3RW55 soft starter........................................................ 71
5.2 Overview of all connections of the 3RW55 Failsafe soft starter............................................ 73
5.3 Connecting 3RW55 and 3RW55 Failsafe soft starters........................................................... 74
5.4 Connecting the 3RW55 and 3RW55 Failsafe soft starters to the main circuit connection
(line side/motor side) ......................................................................................................... 75
5.5 Mounting terminal covers on main circuit connections ....................................................... 76
5.6 Replacement of the box terminal blocks with size 2 ............................................................ 78
5.7 Connecting the control terminals (screw terminals) ............................................................ 80
5.8 Disconnecting the control current form the screw-type terminals........................................ 81
5.9 Connecting the control terminals (spring-type terminals).................................................... 82
5.10 Disconnecting the control current from the spring-loaded terminals ................................... 83
5.11 Replacing the control terminals .......................................................................................... 84
5.12 Installing the cover for the control cable duct ..................................................................... 86
5.13 Removing the cover of the control cable duct ..................................................................... 87
6 Parameter assignment......................................................................................................................... 89
6.1 Parameterizing 3RW55 and 3RW55 Failsafe soft starters ..................................................... 89
6.2 Parameter sets ................................................................................................................... 91
6.3 Application wizard ............................................................................................................. 92
6.4 Suggested settings of the application wizard ...................................................................... 93
6.5 Motor parameters .............................................................................................................. 95
6.6 Design and operator controls of the High Feature 3RW5 HMI .............................................. 98
6.7 Menu of the 3RW5 HMI High Feature ................................................................................. 99
6.8 Con󹪝guring the Function selection key F1-F9 of the 3RW5 HMI High Feature .................... 117
6.9 Con󹪝guring the start key of the 3RW5 HMI High Feature................................................... 119
6.10 Parameterizing the 3RW5 HMI High Feature ..................................................................... 121
6.11 Parameterizing the 3RW55 or 3RW55 Failsafe soft starter in series / identically .................. 123
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6.11.1 Parameterizing the 3RW55 or 3RW55 Failsafe soft starter with micro SD card in series /
identically........................................................................................................................ 123
6.11.2 Parameterizing the 3RW55 or 3RW55 Failsafe soft starter in series / identically with SIRIUS
Soft Starter ES (TIA Portal)................................................................................................ 124
7 Commissioning .................................................................................................................................. 125
7.1 Commissioning 3RW55 and 3RW55 Failsafe soft starters................................................... 125
7.2 Sealing 3RW55 and 3RW55 Failsafe soft starters (optional) ............................................... 126
7.3 First commissioning of the High Feature 3RW5 HMI.......................................................... 127
8 Functions ........................................................................................................................................... 129
8.1 Start-up ........................................................................................................................... 131
8.1.1 Starting modes ................................................................................................................ 131
8.1.2 Automatic parameterization............................................................................................. 132
8.1.3 Soft starting with voltage ramp........................................................................................ 134
8.1.4 Soft starting with torque control ...................................................................................... 137
8.1.5 Soft starting with voltage ramp and current limiting......................................................... 140
8.1.6 Soft starting with torque control and current limiting ....................................................... 142
8.1.7 Direct-on-line starting ...................................................................................................... 143
8.1.8 Motor heating.................................................................................................................. 143
8.1.9 Breakaway pulse for startup functions .............................................................................. 144
8.2 Run-down........................................................................................................................ 146
8.2.1 Stopping modes............................................................................................................... 146
8.2.2 Coasting down................................................................................................................. 148
8.2.3 Voltage ramp ................................................................................................................... 149
8.2.4 Torque control ................................................................................................................. 150
8.2.5 Pump stop ....................................................................................................................... 152
8.2.6 DC braking....................................................................................................................... 154
8.2.6.1 DC braking with external braking contactors..................................................................... 154
8.2.6.2 Dynamic DC braking without contactor ............................................................................ 157
8.2.6.3 Reversing DC braking with a reversing contactor assembly................................................ 160
8.2.6.4 Sensorless motor standstill detection................................................................................ 162
8.2.6.5 External motor standstill detection ................................................................................... 162
8.2.7 Alternative stopping......................................................................................................... 163
8.3 Motor protection.............................................................................................................. 166
8.3.1 Electronic motor overload protection................................................................................ 166
8.3.2 Temperature sensor ......................................................................................................... 169
8.4 Intrinsic device protection ................................................................................................ 171
8.5 Creep speed..................................................................................................................... 172
8.6 Reset ............................................................................................................................... 173
8.7 Quick-stop ....................................................................................................................... 174
8.8 Condition Monitoring....................................................................................................... 174
8.8.1 Condition Monitoring for plant monitoring....................................................................... 174
8.8.2 Current monitoring .......................................................................................................... 175
8.8.3 Active power monitoring.................................................................................................. 177
8.8.4 Switching frequency monitoring ...................................................................................... 178
8.8.5 Starting time monitoring.................................................................................................. 181
8.8.6 Pump cleaning function ................................................................................................... 182
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8.9 Asymmetry ...................................................................................................................... 186
8.10 Ground fault .................................................................................................................... 187
8.11 Emergency mode............................................................................................................. 189
8.11.1 Emergency start............................................................................................................... 189
8.11.2 Emergency run ................................................................................................................ 191
8.12 Inputs.............................................................................................................................. 194
8.12.1 Overview of the input functions ....................................................................................... 194
8.12.2 Process data and process images...................................................................................... 196
8.13 Outputs ........................................................................................................................... 198
8.13.1 Digital outputs................................................................................................................. 198
8.13.2 Analog output ................................................................................................................. 202
8.13.3 Cyclic send data ............................................................................................................... 205
8.14 ATEX / IECEx..................................................................................................................... 206
8.14.1 ATEX/IECEx-certi󹪝ed motor overload protection ................................................................ 206
8.14.2 Ex operation .................................................................................................................... 207
8.15 Failsafe ............................................................................................................................ 212
8.15.1 Operating principle .......................................................................................................... 212
8.15.2 Resetting safety-related shuto󹪜 ........................................................................................ 213
8.16 Functions under "Additional parameters".......................................................................... 214
8.17 Setting the date and time................................................................................................. 218
8.18 Trace ............................................................................................................................... 220
8.19 Test mode........................................................................................................................ 221
8.19.1 Test with small load ......................................................................................................... 222
8.19.2 Simulation....................................................................................................................... 224
8.20 Monitoring ...................................................................................................................... 227
8.20.1 Monitoring the measured values of the 3RW55 soft starter with the 3RW5 HMI High
Feature............................................................................................................................ 227
8.20.2 Graphical display of measured values on the 3RW5 HMI High Feature ............................... 229
8.20.3 Monitoring the process image of the 3RW55 soft starter with the 3RW5 HMI High Feature... 231
8.21 Control via 3RW5 HMI High Feature.................................................................................. 232
8.22 Overview......................................................................................................................... 234
8.23 Local access protection and user account administration .................................................. 237
8.23.1 General advice on using PINs ........................................................................................... 237
8.23.2 Local access protection (PIN)............................................................................................ 237
8.23.2.1 De󹪝ne PIN........................................................................................................................ 238
8.23.2.2 Change PIN...................................................................................................................... 239
8.23.2.3 Delete PIN........................................................................................................................ 239
8.23.3 Setting up user account management .............................................................................. 240
8.23.4 User login and logout....................................................................................................... 242
8.24 Micro SD card .................................................................................................................. 243
8.25 Reloading a language for the High Feature 3RW5 HMI ...................................................... 245
9 Messages and diagnostics ................................................................................................................. 247
9.1 Diagnostics options.......................................................................................................... 247
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9.2 LED display ...................................................................................................................... 247
9.2.1 Overview of the device LEDs on the 3RW55 and 3RW55 Failsafe soft starters .................... 247
9.2.2 Status and error displays .................................................................................................. 248
9.2.3 Overview of LEDs on High Feature 3RW5 HMI................................................................... 249
9.3 Warnings and remedial measures of the 3RW55 and 3RW55 Failsafe soft starters.............. 250
9.4 Errors and remedial actions of the 3RW55 and 3RW55 Failsafe soft starters....................... 252
9.5 Faults and remedial actions of the 3RW5 HMI High Feature............................................... 256
9.6 Performing diagnostics on the 3RW55 and 3RW55 Failsafe soft starters using the 3RW5
HMI High Feature............................................................................................................. 257
9.7 Execute HMI diagnostics with the 3RW5 HMI High Feature................................................ 263
9.8 Performing diagnostics of the 3RW5 communication module with the 3RW5 HMI High
Feature............................................................................................................................ 263
9.9 Self-test (user-test) .......................................................................................................... 264
9.10 Logbooks......................................................................................................................... 265
9.11 Save service data to micro SD card ................................................................................... 266
10 Maintenance and service .................................................................................................................. 269
10.1 Maintenance and repairs.................................................................................................. 269
10.2 Replacing the fan............................................................................................................. 269
10.3 Firmware update.............................................................................................................. 275
10.4 Performing 󹪝rmware update with micro SD card (3RW5 HMI High Feature) ....................... 277
10.5 Restoring factory setting .................................................................................................. 278
10.5.1 Restoring the factory settings via High Feature 3RW5 HMI ................................................ 279
10.5.2 Restoring the factory settings with the Master RESET button via 3RW5 HMI High Feature... 280
10.6 "Device change" function ................................................................................................. 281
10.6.1 Device change with micro SD card on the 3RW5 HMI High Feature.................................... 282
10.6.2 Device change with SIRIUS Soft Starter ES (TIA Portal)....................................................... 283
11 Technical speci󹪝cations ..................................................................................................................... 285
11.1 Technical data in Siemens Industry Online Support........................................................... 285
12 Dimension drawings.......................................................................................................................... 287
12.1 CAx data.......................................................................................................................... 287
12.2 Drilling pattern for 3RW5 HMI High Feature ...................................................................... 287
13 Circuit diagrams................................................................................................................................. 289
13.1 CAx data.......................................................................................................................... 289
A Example circuits................................................................................................................................. 291
A.1 Main circuit connection.................................................................................................... 291
A.1.1 Feeder assembly, type of coordination 1 fuseless.............................................................. 291
A.1.2 Feeder assembly, type of coordination 1 with fuses .......................................................... 293
A.1.3 Feeder assembly, type of coordination 2........................................................................... 294
A.1.4 Inside-delta circuit ........................................................................................................... 295
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A.2 Control circuit connection ................................................................................................ 299
A.2.1 Control by PLC ................................................................................................................. 299
A.2.2 Control by switch............................................................................................................. 300
A.2.3 Actuation of a line contactor ............................................................................................ 302
A.2.4 Connecting the temperature sensor ................................................................................. 303
A.2.5 Connecting the evaluation unit to the analog output........................................................ 304
A.3 Special applications ......................................................................................................... 305
A.3.1 3RW55 and 3RW55 Failsafe soft starters in Ex operation ................................................... 305
A.3.1.1 Type of motor connection "Standard" (inline) in Ex operation............................................ 305
A.3.1.2 Type of motor connection "inside delta" in Ex operation.................................................... 307
A.3.2 3RW55 soft starter in standard (inline) circuit and stopping function DC braking with one
braking contactor ............................................................................................................ 311
A.3.3 3RW55 soft starter in standard (inline) circuit and stopping function DC braking with 2
braking contactors ........................................................................................................... 313
A.3.4 3RW55 soft starter in standard (inline) circuit with soft starting, soft stopping and the
additional function "Creep speed"..................................................................................... 315
A.3.5 Control via 󹪝eldbus with switchover to manual local operation ......................................... 317
A.3.6 Pump cleaning function ................................................................................................... 318
A.3.6.1 Pump cleaning function with creep speed ........................................................................ 318
A.3.6.2 Pump cleaning function with reversing contactor ............................................................. 320
A.3.7 Reversing duty ................................................................................................................. 322
A.3.8 3RW55 soft starter for serial starting with 3 parameter sets .............................................. 323
A.3.9 Soft starter for pole-changing motor with separate windings and 2 parameter sets ........... 328
A.3.10 3RW55 soft starter with direct-on-line starting (DOL) as emergency start.......................... 330
A.3.11 Starting a Dahlander motor.............................................................................................. 331
A.3.12 External bypass................................................................................................................ 334
A.3.13 EMERGENCY STOP shutdown to SIL 1 or PL c with a 3SK1 safety relay without the 3RW55
Failsafe soft starter .......................................................................................................... 335
A.3.14 EMERGENCY STOP shutdown up to SIL 3 or PL e with a 3SK1 safety relay without the
3RW55 Failsafe soft starter............................................................................................... 339
A.4 3RW55 Failsafe soft starter............................................................................................... 343
A.4.1 EMERGENCY STOP shutdown to SIL 1 STO with a 3RW55 Failsafe soft starter..................... 345
A.4.2 EMERGENCY STOP shutdown to SIL 3 STO with a 3RW55 Failsafe soft starter without
coupling of the digital input DI to the failsafe digital input F-DI ......................................... 347
A.4.3 EMERGENCY STOP shutdown to SIL 3 STO with a 3RW55 Failsafe soft starter with coupling
of the digital input DI to the failsafe digital input F-DI ....................................................... 352
A.4.4 EMERGENCY STOP shutdown to SIL 3 STO with a 3RW55 Failsafe soft starter in
conjunction with bus communication and a safety control................................................ 356
Glossary ............................................................................................................................................. 359
Index .................................................................................................................................................. 361
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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)
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/ww/en/ps)
SIRIUS 3RW55 and 3RW55 Failsafe Soft Starters
Equipment Manual, 02/2022, A5E35630887002A/RS-AF/006 9

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.
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
SIRIUS 3RW55 and 3RW55 Failsafe Soft Starters
10 Equipment Manual, 02/2022, A5E35630887002A/RS-AF/006

1.1 Support Request
After you have registered, you can use the Support Request form in the online support to send
your question directly to Technical Support:
Support Request: Internet (https://www.siemens.com/support-request)
1.2 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 3RW50 soft starter (https://support.industry.siemens.com/cs/ww/
en/view/109753750)
• Equipment Manual for the 3RW52 soft starter (https://support.industry.siemens.com/cs/ww/
en/view/109753751)
• Equipment Manual for the 3RW55 and 3RW55 Failsafe Soft Starters (https://
support.industry.siemens.com/cs/ww/en/view/109753752)
• Equipment Manuals for the 3RW5 soft starter (https://support.industry.siemens.com/cs/ww/
en/ps/16212/man)
• Equipment Manual for the 3RW5 PROFINET communication modules (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)
• Equipment Manual for the 3RW5 Modbus communication modules (https://
support.industry.siemens.com/cs/ww/en/view/109753755)
• Equipment Manual for the 3RW5 EtherNet/IP communication module (https://
support.industry.siemens.com/cs/ww/en/view/109758201)
• Online help for SIRIUS Soft Starter ES (TIA Portal)
• Online help for STEP 7
• The EMC Directive 2014/30/EU in practice (http://www.siemens.com/emc-guideline)
• Industrial Control Panels and Electronic Equipment of Industrial Machinery for North
America (http://www.siemens.com/UL508A)
• Control Panels compliant with IEC Standards and European Directives (http://
www.siemens.com/iec60204)
Siemens Industry Online Support
1.2 Additional documentation
SIRIUS 3RW55 and 3RW55 Failsafe Soft Starters
Equipment Manual, 02/2022, A5E35630887002A/RS-AF/006 11

Interesting links
• 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)
• Catalog IC 10 (https://support.industry.siemens.com/cs/ww/en/view/109747945)
• Product support for STEP 7 (TIA Portal) (https://support.industry.siemens.com/cs/ww/en/ps/
14672)
Siemens Industry Online Support
1.2 Additional documentation
SIRIUS 3RW55 and 3RW55 Failsafe Soft Starters
12 Equipment Manual, 02/2022, A5E35630887002A/RS-AF/006

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 3RW55 and 3RW55 Failsafe Soft Starters
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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 this is unavoidable (e.g.
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 in DIN VDE 0105 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 re-connection
3. Verify absence of operating voltage
4. Ground and short-circuit
5. Provide protection against 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.
It is assumed that every electrically skilled person is familiar with these rules.
Safety information
2.2 Five safety rules for working in or on electrical systems
SIRIUS 3RW55 and 3RW55 Failsafe Soft Starters
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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)
Do not connect any capacitors to the output terminals of the 3RW5 soft starter. If capacitors are
connected to the output terminals, the 3RW5 soft starter will be damaged.
Do not operate active 󹪝lters, e.g. for reactive power compensation, parallel to the 3RW5 soft
starter.
If you use capacitors to correct the power factor (actively or passively), you must connect them
on the line side of the 3RW5 soft starter. Make sure that the capacitors do not actively control the
power factor during the starting and coasting down phases. If you use a contactor disconnector
or main contactor together with the 3RW5 soft starter, the capacitors must be disconnected
from the 3RW5 soft starter when the contactor is open.
You will 󹪝nd further information in the Internet (https://
support.industry.siemens.com/cs/ww/en/view/67131557).
2.4 Electromagnetic compatibility (EMC) according to IEC 60947-4-2
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 60947-4-2
SIRIUS 3RW55 and 3RW55 Failsafe Soft Starters
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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 constitute one element of such a concept.
Customers are responsible for preventing unauthorized access to their plants, systems,
machines and networks. Such systems, machines and components should only be connected to
an enterprise network or the internet if and to the extent such a connection is necessary and only
when appropriate security measures (e.g. 󹪝rewalls and/or network segmentation) are in place.
For additional information on industrial security measures that may be implemented, please
visit
https://www.siemens.com/industrialsecurity.
Siemens’ products and solutions undergo continuous development to make them more secure.
Siemens strongly recommends that product updates are applied as soon as they are available
and that the latest product versions are used. Use of product versions that are no longer
supported, and failure to apply the 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/cert.
2.6 ATEX / IECEx
2.6.1 Use in Class I and Class II Hazardous Locations
The components of the 3RW55 and 3RW55 Failsafe soft starters are not suitable for installation
in Class I and Class II Hazardous Locations .
Use the device only in a control cabinet with at least degree of protection IP 4x.
If you have any questions, ask your ATEX/IECEx expert.
2.6.2 ATEX/IECEx-certi󹪝ed motor overload protection
Environmental conditions
Comply with the ambient conditions for which the 3RW55 and 3RW55 Failsafe soft starters are
approved.
Note that the 3RW55 and 3RW55 Failsafe soft starters are approved for operation in a
temperature range of -25 °C to +60 °C. Consider the derating of the rated operational current at
ambient temperatures higher than 40 °C. You will 󹪝nd further information on derating in the
Safety information
2.6 ATEX / IECEx
SIRIUS 3RW55 and 3RW55 Failsafe Soft Starters
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Technical speci󹪝cations (Page 285) in section "Power electronics" or in Catalog IC 10 (https://
support.industry.siemens.com/cs/ww/en/view/109747945).
Note
Temperature sensor
For ATEX / IECEx-certi󹪝ed motor protection, use of the PTC type A sensor only is approved.
Note
Simulation Tool for Soft Starters
Note that the Simulation Tool for Soft Starters (Page 44) already takes into account the derating
for certain ambient temperatures, when you select a suitable 3RW5 soft starter.
Parameterization of the 3RW55 and 3RW55 Failsafe soft starters
You are supported with parameterizing 3RW55 and 3RW55 Failsafe soft starters for ATEX / IECEx
applications by the menu in the 3RW5 HMI High Feature. Activate the function "Ex application"
(Page 207) to deactivate impermissible settings of the ATEX/IECEx relevant parameters. Set all
relevant parameters in the same menu.
Setting the rated motor operational current
Set the 3RW55 or 3RW55 Failsafe soft starters to the rated operational current of the motor as
stated on the type plate or design test certi󹪝cate of the motor.
Trip class (electronic overload protection)
Make sure that the motor and the cables are dimensioned for the selected trip class.
The rated data of the 3RW55 and 3RW55 Failsafe soft starters refers to normal starting
(CLASS 10E). For heavy starting (> CLASS 10E) you may have to overdimension the 3RW55 or
3RW55 Failsafe soft starter.
Parameterizing the motor protection functions (RESET setting)
Note that the "Auto RESET" setting is not permissible when operating motors in Class I and Class
II Hazardous Locations.
If you have activated the function "Ex application" (Page 207), the parameter "Response to
overload" is permanently set to "Turn o󹪜 without restart".
Short-circuit protection
The 3RW55 and 3RW55 Failsafe soft starters do not include short-circuit protection. Make sure
that short-circuit protection is provided.
Safety information
2.6 ATEX / IECEx
SIRIUS 3RW55 and 3RW55 Failsafe Soft Starters
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Line protection
Avoid impermissibly high cable surface temperatures by correctly dimensioning conductor cross
sections. Select a su󹪟ciently large conductor cross section.
Emergency start and emergency run not permissible
If the motor is operated in Class I and Class II Hazardous Locations, the functions "emergency
start" (Page 189) and "emergency run" (Page 191) are not permissible.
Cyclic test of the motor protection functions
Note that performing the self-test (user-test) without 3RW5 HMI High Feature results in loss of
the certi󹪝ed motor overload protection according to ATEX / IECEx and there will be no explosion
protection.
Only perform the self-test (user-test) (Page 264) locally with the 3RW5 HMI High Feature to
ensure that the correct 3RW55 or 3RW55 Failsafe soft starter is tested. Only in this way can the
certi󹪝ed motor overload protection according to ATEX/IECEx be guaranteed.
On 3RW55 or 3RW55 Failsafe soft starters in ATEX / IECEx applications, perform the self-test
(user-test) (Page 264) during commissioning and periodically at intervals of no more than
36 months.
Certi󹪝cation of the 3RW55 and 3RW55 Failsafe soft starters
Note
Firmware versions and product versions of the 3RW55 soft starter with ATEX / IECEx
certi󹪝cation
For 3RW55 soft starters, certi󹪝ed motor overload protection according to ATEX / IECEx is only
provided from 󹪝rmware version V2.0 and product version E02 (does not apply to 3RW55 Failsafe
soft starters).
Note that it is not possible to downgrade to a previous 󹪝rmware version because, in that case,
certi󹪝ed motor overload protection according to ATEX / IECEx cannot be guaranteed.
The motor overload protection of the 3RW55 and 3RW55 Failsafe soft starters is ATEX / IECEx-
certi󹪝ed to SIL 1.
The 3RW55 and 3RW55 Failsafe soft starters are approved under Equipment Groups I and II,
Category (2) or (M2) in zones "G" and "D". Zones "G" and "D" are areas in which explosive gas,
vapor, mist or air mixtures and combustible dust are present:
IECEx BVS 19.0014 X [Ex]
BVS 18 ATEX F003 X
II (2)G [Ex eb Gb] [Ex db Gb] [Ex pxb Gb]1)
II (2)D [Ex tb Db] [Ex pxb Db]
I (M2) [Ex db Mb]
Safety information
2.6 ATEX / IECEx
SIRIUS 3RW55 and 3RW55 Failsafe Soft Starters
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1) For the pxb applications, pressure and 󹪞ow rate monitoring are additionally required for the
overpressure encapsulation systems.
Type of motor connection "Standard" (inline)
Note that operation of a 3RW55 soft starter in the motor connection type "Standard" without
implementing one of the two following remedial measures for the following line voltages results
in loss of certi󹪝ed motor overload protection according to ATEX/IECEx (does not apply to 3RW55
Failsafe soft starters):
• Soft starter 200 - 480 V: for line voltage > 440 V (+10%)
• Soft starter 200 - 600 V: for line voltage > 500 V (+10%)
• Soft starter 200 - 690 V: for line voltage > 560 V (+10%)
Depending on the structure of the circuit, choose one of the following possibilities for ensuring
certi󹪝ed motor overload protection according to ATEX / IECEx:
• Use an additional line contactor in the main circuit.
Connect the line contactor at outputs 95, 96 and 98 (output 3).
You will 󹪝nd more information in chapter Type of motor connection "Standard" (inline) in Ex
operation (Page 305).
• For a motor feeder con󹪝guration with a circuit breaker, use an additional undervoltage trip
unit.
Connect the undervoltage trip unit at outputs 95, 96 and 98 (output 3).
You will 󹪝nd more information in chapter Connecting (Page 71).
The motor connection type "Automatic detection" is not approved for ATEX/IECEx applications.
Type of motor connection "Inside delta"
Note that operation of a 3RW55 or 3RW55 Failsafe soft starter with motor connection type
"Inside-delta" without implementing one of the two following remedial measures results in loss
of certi󹪝ed motor overload protection according to ATEX/IECEx:
Depending on the structure of the circuit, choose one of the following possibilities for ensuring
certi󹪝ed motor overload protection according to ATEX / IECEx:
• Use an additional line contactor in the main circuit (in the supply cable or in the delta
connection).
Connect the line contactor at outputs 95, 96 and 98 (output 3).
You will 󹪝nd more information in chapter Type of motor connection "inside delta" in Ex
operation (Page 307).
• For a motor feeder con󹪝guration with a circuit breaker, use an additional undervoltage trip
unit.
Connect the undervoltage trip unit at outputs 95, 96 and 98 (output 3).
You will 󹪝nd more information in chapter Connecting (Page 71).
The motor connection type "Automatic detection" is not approved for ATEX/IECEx applications.
Safety information
2.6 ATEX / IECEx
SIRIUS 3RW55 and 3RW55 Failsafe Soft Starters
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Complying with standards
Increased danger in Class I and Class II Hazardous Locations means it is necessary to comply with
the following standards carefully:
•IEC / EN 60079-14 / VDE 0165-1: For electrical apparatus for Class I and Class II Hazardous
Locations.
•IEC / EN 60079-17: Inspection and maintenance of electrical installations in hazardous areas.
•EN 50495: Safety devices required for the safe functioning of equipment with respect to
explosion risks.
ATEX/IECEx-speci󹪝c safety data
You will 󹪝nd ATEX / IECEx-speci󹪝c safety data on the 3RW55 and 3RW55 Failsafe soft starters in
the Technical speci󹪝cations (Page 285).
Maintenance and repairs
The 3RW55 and 3RW55 Failsafe soft starters are maintenance-free. The repair of soft starters
with approval according to IEC 61508 / EN ISO 13849 is only permissible in the manufacturer's
plant.
Any repair to the 3RW55 and 3RW55 Failsafe soft starters that is not performed in the
manufacturer's plant will result in loss of ATEX/IECEx approval.
Restoration of the factory setting of the 3RW55 soft starter
Restoration of the factory setting of the 3RW55 or 3RW55 Failsafe soft starter in active Ex
operation is only permissible via the master RESET button on the 3RW5 HMI High Feature. This
resets the parameters of the 3RW55 and 3RW55 Failsafe soft starters to the factory settings.
After restoration of the factory settings, you have to parameterize the 3RW55 and 3RW55
Failsafe soft starters again for use in Class I and Class II Hazardous Locations.
You will 󹪝nd further information on parameterization of the 3RW55 and 3RW55 Failsafe soft
starters for use in Class I and Class II Hazardous Locations in chapter Ex operation (Page 207).
2.7 Failsafe
WARNING
Loss of the safety function due to incorrectly set rated operational current Ie.
Can cause death or serious injury.
Using a motor with too low rated operational current Ie can disable error detection
mechanisms. Safety-related shuto󹪜 by the safety function "Safe Torque O󹪜" (STO) can no longer
be guaranteed.
Make sure that the rated operational current Ie of the motor is in the range of the settable rated
operational current Ie of the 3RW55 Failsafe soft starter used.
Safety information
2.7 Failsafe
SIRIUS 3RW55 and 3RW55 Failsafe Soft Starters
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