Siemens SIRIUS 3SK1 User manual

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Industrial Controls
Safety engineering
SIRIUS 3SK1 safety relays
Manual
06/2018
A5E02526190021A/RS
-AD/004
Introduction
1
Product-specific safety
information
2
Product overview for 3SK1
3
Safety systems - General
information
4
3SK1 devices
5
System configuration
6
Circuit diagrams
7
Mounting
8
Connection
9
Configuration / operation
10
Commissioning
11
Display and diagnostics
12
Technical data
13
Dimension drawings
14
Accessories
15

Siemens AG
Division Digital Factory
Postfach 48 48
90026 NÜRNBERG
GERMANY
3ZX1012-0SK11-0AC0
Ⓟ
06/2018 Subject to change
Copyright © Siemens AG 2013.
All rights reserved
Legal information
Warning notice system
This manual contains notices you have to observe in order to ensure your personal safety, as well as to prevent
damage to property. The notices referring to your personal safety are highlighted in the manual by a safety alert
symbol, notices referring only to property damage have no safety alert symbol. These notices shown below are
graded according to the degree of danger.
DANGER
indicates that death or severe personal injury will result if proper precautions are not taken.
WARNING
indicates that death or severe personal injury may result if proper precautions are not taken.
CAUTION
indicates that minor personal injury can result if proper precautions are not taken.
NOTICE
indicates that property damage can result if proper precautions are not taken.
If more than one degree of danger is present, the warning notice representing the highest degree of danger will
be used. A notice warning of injury to persons with a safety alert symbol may also include a warning relating to
property damage.
Qualified Personnel
The product/system described in this documentation may be operated only by
personnel qualified
for the specific
task in accordance with the relevant documentation, in particular its warning notices and safety instructions.
Qualified personnel are those who, based on their training and experience, are capable of identifying risks and
avoiding potential hazards when working with these products/systems.
Proper use of Siemens products
Note the following:
WARNING
Siemens products may only be used for the applications described in the catalog and in the relevant technical
documentation. If products and components from other manufacturers are used, these must be recommended
or approved by Siemens. Proper transport, storage, installation, assembly, commissioning, operation and
maintenance are required to ensure that the products operate safely and without any problems. The permissible
ambient conditions must be complied with. The information in the relevant documentation must be observed.
Trademarks
All names identified by ® are registered trademarks of Siemens AG. The remaining trademarks in this publication
may be trademarks whose use by third parties for their own purposes could violate the rights of the owner.
Disclaimer of Liability
We have reviewed the contents of this publication to ensure consistency with the hardware and software
described. Since variance cannot be precluded entirely, we cannot guarantee full consistency. However, the
information in this publication is reviewed regularly and any necessary corrections are included in subsequent
editions.

SIRIUS 3SK1 safety relays
Manual, 06/2018, A5E02526190021A/RS-AD/004 3
Table of contents
1 Introduction................................................................................................................................................ 9
1.1 User responsibility for system design and function ..................................................................9
1.2 Required basic knowledge........................................................................................................9
1.3 Validity range ............................................................................................................................9
1.4 Definitions .................................................................................................................................9
1.5 Service&Support.....................................................................................................................10
1.6 Configurator for 3SK1 safety relays........................................................................................12
1.7 DataMatrix code......................................................................................................................12
1.8 Correction sheet......................................................................................................................13
1.9 History.....................................................................................................................................13
2 Product-specific safety information .......................................................................................................... 15
2.1 General safety notes...............................................................................................................15
2.2 Intended use ...........................................................................................................................18
2.3 Current information about operational safety .........................................................................18
2.4 Declaration of conformity ........................................................................................................19
3 Product overview for 3SK1 ...................................................................................................................... 21
3.1 Overview .................................................................................................................................21
3.2 Overview of components and accessory parts.......................................................................24
3.3 Functional scope of the 3SK1 basic units...............................................................................25
3.4 Introduction .............................................................................................................................26
3.5 3SK1 system...........................................................................................................................27
3.5.1 Standard .................................................................................................................................27
3.5.1.1 Typical system configuration ..................................................................................................27
3.5.2 Advanced ................................................................................................................................28
3.5.2.1 Typical system configuration ..................................................................................................28
4 Safety systems - General information...................................................................................................... 31
4.1 What is safety? .......................................................................................................................31
4.2 Safety function ........................................................................................................................31
4.3 Basic terminology....................................................................................................................33
4.3.1 Redundancy/single-channel and two-channel........................................................................33
4.3.2 Cross-circuit detection ............................................................................................................34
4.3.3 Enabling circuit (safety-related output) ...................................................................................34
4.3.4 Signaling circuit.......................................................................................................................35
4.3.5 Feedback circuit......................................................................................................................35

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4.3.6 Stop categories ...................................................................................................................... 35
4.3.7 Automatic start ....................................................................................................................... 36
4.3.8 Manual start ........................................................................................................................... 36
4.3.9 Monitored start ....................................................................................................................... 37
4.3.10 Two-hand operation/synchronism.......................................................................................... 38
4.3.11 Cascading .............................................................................................................................. 39
4.3.12 Startup testing........................................................................................................................ 39
4.3.13 Connection of actuators ......................................................................................................... 40
4.3.14 Series connection of sensors................................................................................................. 44
4.3.15 Use of magnetically operated switches ................................................................................. 45
5 3SK1 devices........................................................................................................................................... 47
5.1 3SK1 standard ....................................................................................................................... 47
5.1.1 General information ............................................................................................................... 47
5.1.2 Applications............................................................................................................................ 47
5.1.3 3SK1111 Standard basic unit instantaneous (with relay outputs) ......................................... 48
5.1.3.1 General information ............................................................................................................... 48
5.1.3.2 Function description............................................................................................................... 48
5.1.3.3 Design .................................................................................................................................... 49
5.1.3.4 Terminal assignment.............................................................................................................. 50
5.1.3.5 Inputs ..................................................................................................................................... 51
5.1.3.6 Outputs................................................................................................................................... 51
5.1.3.7 Display of the operating state ................................................................................................ 52
5.1.3.8 Function setting...................................................................................................................... 52
5.1.4 3SK1112 Standard basic unit instantaneous (with semiconductor outputs) ......................... 55
5.1.4.1 General information ............................................................................................................... 55
5.1.4.2 Function description............................................................................................................... 56
5.1.4.3 Design .................................................................................................................................... 57
5.1.4.4 Terminal assignment.............................................................................................................. 58
5.1.4.5 Inputs ..................................................................................................................................... 58
5.1.4.6 Outputs................................................................................................................................... 59
5.1.4.7 Display of the operating state ................................................................................................ 59
5.1.4.8 Function setting...................................................................................................................... 60
5.2 3SK1 Advanced ..................................................................................................................... 62
5.2.1 General information ............................................................................................................... 62
5.2.2 Applications............................................................................................................................ 62
5.2.3 General device features......................................................................................................... 63
5.2.4 Function description............................................................................................................... 63
5.2.5 Functions................................................................................................................................ 64
5.2.6 3SK1121 Advanced basic unit instantaneous (with relay outputs)........................................ 65
5.2.6.1 Device features ...................................................................................................................... 65
5.2.6.2 Function description............................................................................................................... 66
5.2.6.3 Design .................................................................................................................................... 66
5.2.6.4 Terminal assignment.............................................................................................................. 67
5.2.7 3SK1121 Advanced basic unit time-delayed (with relay outputs).......................................... 68
5.2.7.1 Device features ...................................................................................................................... 68
5.2.7.2 Design .................................................................................................................................... 69
5.2.7.3 Terminal assignment.............................................................................................................. 70
5.2.8 3SK1122 Advanced basic unit instantaneous (with semiconductor outputs)........................ 72
5.2.8.1 Device features ...................................................................................................................... 72
5.2.8.2 Design .................................................................................................................................... 73
5.2.8.3 Terminal assignment.............................................................................................................. 74

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5.2.9 3SK1122 Advanced basic unit time-delayed (with semiconductor outputs)...........................76
5.2.9.1 Device features.......................................................................................................................76
5.2.9.2 Design.....................................................................................................................................77
5.2.9.3 Terminal assignment...............................................................................................................78
5.2.10 3SK1120 Advanced basic unit instantaneous (with semiconductor outputs).........................80
5.2.10.1 Device features.......................................................................................................................80
5.2.10.2 Design.....................................................................................................................................81
5.2.10.3 Terminal assignment...............................................................................................................82
5.2.10.4 Status diagrams......................................................................................................................82
5.3 3SK1 output expansions.........................................................................................................84
5.3.1 Applications.............................................................................................................................84
5.3.2 Function description................................................................................................................85
5.3.3 Display of the operating state .................................................................................................85
5.3.4 Function setting.......................................................................................................................85
5.3.5 Output expansion 3SK1211....................................................................................................86
5.3.5.1 Device features.......................................................................................................................86
5.3.5.2 Design of 3SK1211-.B..0 ........................................................................................................87
5.3.5.3 Design of 3SK1211-.BB40......................................................................................................88
5.3.5.4 Terminal assignment...............................................................................................................89
5.3.6 Output expansion 3SK1213....................................................................................................89
5.3.6.1 Device features.......................................................................................................................89
5.3.6.2 Design of 3SK1213-.AB40......................................................................................................90
5.3.6.3 Design of 3SK1213-.A.20 .......................................................................................................91
5.3.6.4 Terminal assignment...............................................................................................................91
5.3.7 3RM1 Failsafe motor starters .................................................................................................92
5.4 3SK1 input expansions ...........................................................................................................93
5.4.1 Input expansion 3SK1220.......................................................................................................93
5.4.1.1 Device features.......................................................................................................................93
5.4.1.2 Applications.............................................................................................................................93
5.4.1.3 Design.....................................................................................................................................94
5.4.1.4 Terminal assignment...............................................................................................................94
5.4.1.5 Display of the operating state .................................................................................................95
5.4.1.6 Function setting.......................................................................................................................95
5.4.2 Power supply 3SK1230 ..........................................................................................................97
5.4.2.1 Device features.......................................................................................................................97
5.4.2.2 Applications.............................................................................................................................97
5.4.2.3 Design.....................................................................................................................................98
5.4.2.4 Terminal assignment...............................................................................................................99
5.4.2.5 Display of the operating state .................................................................................................99
6 System configuration ............................................................................................................................. 101
6.1 General information ..............................................................................................................101
6.1.1 General notes on the Standard system ................................................................................101
6.1.2 General information on the Advanced system......................................................................101
6.1.3 Maximum system configuration ............................................................................................102
6.2 3ZY12 device connector .......................................................................................................106
6.2.1 Device features.....................................................................................................................106
6.2.2 Applications...........................................................................................................................108
6.3 System configuration rules ...................................................................................................109

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7 Circuit diagrams..................................................................................................................................... 113
7.1 Internal circuit diagrams....................................................................................................... 113
7.1.1 Internal circuit diagrams for 3SK1 Standard basic units...................................................... 113
7.1.2 Internal circuit diagrams for 3SK1 Advanced basic units .................................................... 115
7.1.3 Internal circuit diagrams for expansion units ....................................................................... 117
7.2 Typical circuits...................................................................................................................... 121
7.2.1 Typical circuits...................................................................................................................... 121
7.3 Typical circuits of 3SK1 safety relays with 3RM1 Failsafe motor starters ........................... 131
7.3.1 3SK1 safety relay with 3RM1 Failsafe motor starter via device connector.......................... 131
7.3.2 3SK1 safety relay wired with 3RM1 Failsafe motor starter.................................................. 133
7.4 Additional applications ......................................................................................................... 135
8 Mounting................................................................................................................................................ 137
8.1 Warning notices ................................................................................................................... 137
8.2 Terminal coding.................................................................................................................... 137
8.3 Mounting the devices on a level surface.............................................................................. 138
8.4 Disassembling devices from a level surface........................................................................ 140
8.5 Mounting 22.5 mm/17.5 mm devices on a standard mounting rail...................................... 142
8.6 Mounting the 90 mm devices on a standard mounting rail .................................................. 143
8.7 Removing devices from a standard mounting rail................................................................ 144
8.8 Mounting 22.5 mm/17.5 mm devices with device connectors on a standard mounting
rail ........................................................................................................................................ 145
8.9 Removing 22.5 mm/17.5 mm devices with device connectors from a standard
mounting rail......................................................................................................................... 148
8.10 Mounting 90 mm devices with device connectors on a standard mounting rail .................. 151
8.11 Removing 90 mm devices with device connectors from a standard mounting rail.............. 155
8.12 Mounting 22.5 mm/17.5 mm devices with device connectors on the wall........................... 157
8.13 Removing 22.5 mm/17.5 mm devices with device connectors from the wall ...................... 160
8.14 Mounting 90 mm devices with device connectors on the wall............................................. 163
8.15 Removing 90 mm devices with device connectors from wall .............................................. 166
8.16 Mounting the sealable cover................................................................................................ 168
9 Connection ............................................................................................................................................ 169
9.1 22.5 mm/17.5 mm devices................................................................................................... 169
9.1.1 Terminal assignment............................................................................................................ 169
9.1.2 Connection data for terminals.............................................................................................. 170
9.1.3 Connecting the screw-type terminals................................................................................... 171
9.1.4 Disconnecting the screw-type terminals .............................................................................. 171
9.1.5 Wiring rules for spring-loaded terminals (with push-in technology)..................................... 172
9.1.6 Connecting the push-in terminals ........................................................................................ 173
9.1.7 Disconnecting the push-in terminals.................................................................................... 175
9.1.8 Attaching the terminals ........................................................................................................ 176
9.1.9 Disconnecting....................................................................................................................... 177

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9.2 Devices 90 mm .....................................................................................................................179
9.2.1 Opening the terminal cover...................................................................................................179
9.2.2 Connection data for terminals...............................................................................................180
9.2.3 Connecting terminals ............................................................................................................181
9.2.4 Mounting terminals................................................................................................................183
9.2.5 Disconnecting .......................................................................................................................184
9.3 Device replacement ..............................................................................................................186
10 Configuration / operation ....................................................................................................................... 189
10.1 Procedure for configuration ..................................................................................................189
10.2 Explanation of the device's functions....................................................................................190
10.3 Modes ...................................................................................................................................193
10.4 Response times ....................................................................................................................194
11 Commissioning ...................................................................................................................................... 197
12 Display and diagnostics ......................................................................................................................... 199
12.1 LED display...........................................................................................................................199
12.2 Power-up...............................................................................................................................200
12.3 Error statuses........................................................................................................................200
12.4 Diagnostics ...........................................................................................................................201
13 Technical data ....................................................................................................................................... 203
13.1 Data sheet.............................................................................................................................203
13.2 General technical data..........................................................................................................203
14 Dimension drawings .............................................................................................................................. 209
14.1 Dimension drawings for 3SK1 devices .................................................................................209
14.2 Dimension drawings for 3SK1 device connector..................................................................217
15 Accessories ........................................................................................................................................... 223
Index...................................................................................................................................................... 225

Table of contents
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SIRIUS 3SK1 safety relays
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Introduction
1
1.1
User responsibility for system design and function
The products described here were developed to perform safety-related functions as part of
an overall installation or machine.
A complete, safety-related system is generally equipped with sensors, evaluation units, and
signaling units, and uses reliable shutdown concepts.
It is the responsibility of the manufacturer of a system or machine to ensure that the product
functions properly.
Siemens AG, its regional offices, and associated companies (hereinafter referred to as
"Siemens") cannot guarantee all the properties of an entire plant, system or machine that
has not been designed by Siemens.
Nor can Siemens assume liability for recommendations that appear or are implied in the
following description. No new guarantee, warranty, or liability claims beyond the scope of the
Siemens general terms of supply are to be derived or inferred from the following description.
1.2
Required basic knowledge
A general knowledge of the following areas is needed in order to understand this manual:
●Low-voltage switchgear
●Digital circuit logic
●Automation systems
●Safety systems
1.3
Validity range
The manual is valid for these safety relays SIRIUS 3SK1. It describes the components that
are valid at the time of publication.
SIEMENS reserves the right of including a Product Information for each new component,
and for each component of a later version.
1.4
Definitions
"3SK1" always applies to all variants of the SIRIUS 3SK1 safety relays.

Introduction
1.5 Service&Support
SIRIUS 3SK1 safety relays
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1.5
Service&Support
Online Support
The Online Support in the Service&Support portal is an extensive information system for all
questions relating to Siemens products and solutions. This service enables direct and central
access to in-depth information concerning the products, systems and applications for
industry and to a large number of programming, configuration and application examples. Its
content is available via a mobile app.
The Technical Forum of the Online Support provides the opportunity for users to swap
information. Support Request allows contact to be established with Siemens experts in
Technical Support.
Siemens Industry Online Support ensures that users in industry are always kept up-to-date
with news, software updates and announcements by means of newsletters and Twitter.
Links:
Service&Support Portal (http://support.automation.siemens.com), Online Support
(http://support.automation.siemens.com/WW/view/en/16605022)
Product Support
Are you looking for product information such as technical data, updates or FAQs? Here, the
"Product Support" section of the Service & Support Portal offers an extensive collection of all
information about the Siemens Industry Automation and Drive Technologies products and
solutions:
●Answers to frequently asked questions (FAQs)
●Updates/upgrades, service packs and support tools for downloading
●Manuals and operating instructions
●Technical data/CAx data
●Approvals and certificates
●Test certificates and characteristic curves
All Product Support information is at your disposal free of charge and around the clock, and
you always get the current version.
Link:
Product Support (http://support.automation.siemens.com/WW/view/en/4000024)

Introduction
1.5 Service&Support
SIRIUS 3SK1 safety relays
Manual, 06/2018, A5E02526190021A/RS-AD/004 11
CAx data
The CAx Download Manager provides you with a simple means of gaining access to up-to-
date product data for your CAx or CAe system.
You configure your own download package with just a few clicks. You can choose from the
following information for products
●Product images
●2D dimensional drawings
●3D models
●Internal circuit diagrams
●EPLAN macro files
●Manuals
●Characteristics
●Operating instructions
●Certificates
●Product master data
Link:
CAx Download Manager
(http://support.automation.siemens.com/WW/view/en/42455541)
Applications & Tools
Applications & Tools supports you with various tools and examples when it comes to solving
your automation tasks. Solutions are presented in interaction with several components in the
system, without focusing on individual products.
●Application examples
●Function blocks & tools
●Background and system descriptions
●Performance statements
●Demonstration systems/videos
Link:
Applications & Tools (http://support.automation.siemens.com/WW/view/en/20208582)
My Documentation Manager
My Documentation Manager enables you to compile your own documentation from our
standard documents (manuals), which are located in the Product Support section. Under
mySupport, you have the opportunity to create and manage you own compilations in a
structure of their own.
Link:
MyDocumentationManager (http://support.automation.siemens.com/WW/view/en/38715968)
Reference
You can find further information on structure and navigation in Online Support here
(http://support.automation.siemens.com/WW/view/en/4000024).

Introduction
1.6 Configurator for 3SK1 safety relays
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1.6
Configurator for 3SK1 safety relays
Configurator
Various configurators are available on the Internet to assist you with configuration.
The configurator for 3SK1 safety relays and matching accessories is an easy-to-use
selection and configuration tool. You can select the individual components and plan your
system in accordance with your specific requirements. You can save your selection, export it
as a text file or you can order it directly.
The configurator automatically compiles a document list of the information available in
Service&Support for every component. You can use it as the basis for putting together your
system documentation.
Link:
●Configurator (http://www.siemens.com/industrial-controls/configurators)
1.7
DataMatrix code
A DataMatrix code is lasered onto the lower terminal cover of all 3SK1-series safety relays.
DataMatrix codes are standardized in ISO/IEC 16022. The DataMatrix codes on Siemens
devices use ECC200 coding for powerful error correction.
The following device information is encoded in the DataMatrix codes as a bit stream:
●Article number (MLFB)
●Serial number
●MAC address, if applicable
This information is stored in the following format in the DataMatrix code:
1P
Article number
(MLFB)
+
S serial number
(+ 23S MAC address)
Data identifier
Net content
Separator
Note
The information
content is displayed without spaces.
This machine-readable information simplifies and accelerates handling of the respective
devices.
As well as fast access to the serial numbers of the respective devices for unique
identification, the DataMatrix codes simplify communication with Siemens Technical Support.

Introduction
1.8 Correction sheet
SIRIUS 3SK1 safety relays
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SIEMENS Industry Support App
The Data Matrix codes enable in particular extremely fast and convenient access to all the
device-specific information available on an article number (MLFB) in the SIEMENS
Service&Support Portal, such as operating instructions, manuals, data sheets, FAQs, etc.
We offer the SIEMENS Industry Support App free for this purpose. This can be used on
commercially available smartphones and tablet PCs.
The SIEMENS Industry Support App is available for iOS and Android-based terminal devices
and can be accessed via the following links:
Link for Android
Link for iOS
1.8
Correction sheet
The appendix to this manual contains a correction sheet for evaluation and feedback. Please
use it to record your suggestions for improvements, additions and corrections, and return the
sheet to us. This will help us to improve the next edition of the manual.
Thank you.
1.9
History
Product version
New features
02/2013
Initial release
02/2014 Integration of 3RM1 Failsafe motor starters
09/2015
Revision of the manual

Introduction
1.9 History
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Product-specific safety information
2
2.1
General safety notes
Note
Recycling and disposal
Dispose of existing packing material in accordance with applicable regulations or recycle it.
3SK1 safety relays are able to be recycled thanks to a
low-pollutant manufacturing process.
For environmentally compatible recycling and disposal of your old device, contact a company
certified for the disposal of electronic waste.
Note
SILCL 3 in accordance with IEC 62061:2005PL e / Cat. 4 in accordance with
EN ISO 13849-1: 2008
3SK1 safety relays are designed in such a way as to allow implementation of applications
up to SILCL
3 in accordance with IEC 62061 and PL e/Kat. 4 in accordance with
EN ISO 13849
-1.
Note
Safe state
The basis of the safety function is the definition of the safe state. In the case of safety relays,
this is the "OFF state", i.e. an open contact for sensors or shutdown of the actuators.
WARNING
Protection against electrically conductive contamination!
The devices must be protected against conductive contamination while taking account of
the ambient conditions. You can achieve this by installing the devices in a control cabinet
with the appropriate degree of protection.
You will find more detailed information in IEC 60529, for example.

Product-specific safety information
2.1 General safety notes
SIRIUS 3SK1 safety relays
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WARNING
Safe functional extra-low voltage
The 3SK1 safety relays with a supply voltage of 24 V DC must be operated with safe
functional extra-low voltage (SELV, PELV). This means these modules must only be
subjected to a voltage of Um even in the event of a fault. The following applies for these
3SK1 safety relays:
Um < 60.0 V
.
You can find more detailed information about safe functional extra-low voltage in the data
sheets of the power supplies to be used.
CAUTION
Protection against electrostatic charge
When handling and installing 3SK1 safety relays, ensure that the
components are protected
from being electrostatically charged. Changes to the system configuration and wiring are
only permissible while the supply voltage is switched off.
Connection of 3SK1 safety relays is only permissible when the power supply units (PELV
and SELV) are switched off.
CAUTION
Noise immunity / grounding
The following must be grounded in accordance with the regulations to ensure noise
immunity of the 3SK1 safety relays:
•PELV / SELV power supply units (please also note the documentation for the respective
power supply unit in this regard).
Note
Cover the 3ZY12 device connector on the left
-hand side using the cover supplied with the
device termination connector.

Product-specific safety information
2.1 General safety notes
SIRIUS 3SK1 safety relays
Manual, 06/2018, A5E02526190021A/RS-AD/004 17
WARNING
3SK1..1 and 3SK1..3 safety relays (devices with outputs using contacts):
In continuous operation, the key safety values apply where the function test interval (state
change of the outputs) for SIL2 ≤ 1 year and for SIL3 ≤ 1 month.
Exception: A function test interval ≤ 1 year is also permissible for SIL3 applications in the
process industry (in accordance with IEC 61511), exclusively for low-demand use, due to a
significantly lower failure rate/probability of the electromechanical components. This does
not
apply to safety-related applications in accordance with the Machinery Directive
2006/42/EC.
3SK1..2 and 3SK1120 safety relays (devices with semiconductor outputs up to product
version E01/V1.0.0):
In continuous operation, the key safety values apply where the function test interval (state
change of the outputs) ≤ 1 year.
3SK1..2 and 3SK1120 safety relays (devices with semiconductor outputs from product
version E02/V1.1.0):
In continuous operation, the key safety values apply where the function test interval (state
change of the outputs) ≤ 20 years.
Function test procedure:
•Actuate the connected sensors.
•Check their effect on the safety relay and the downstream actuators.
•Activate the safety relay via the connected sensors.
•Check their effect on the safety relay and the downstream actuators.
•Replace the defective devices.
Note
3SK1..2 and 3SK1120 safety relays (devices with semiconductor outputs) as from
E02/V1.1.0 run power
-on tests, so-called light tests, at regular intervals in the "OFF state".
WARNING
As a result of light tests at the semiconductor outputs, the level changes to the ON state for
up to 2.5 ms. Users are responsible for ensuring that this does not result in any actuator
changing to the active state.
Note
3ZY12 device connectors
Only safety relays with a supply voltage of 24 V DC
may be used on the 3ZY12 device
connector.

Product-specific safety information
2.2 Intended use
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18 Manual, 06/2018, A5E02526190021A/RS-AD/004
2.2
Intended use
WARNING
Hazardous Voltage.
Can Cause Death, Serious Injury, or Property Damage.
Proper use of hardware products
This equipment is only allowed to be used for the applications described in the catalog and
in the technical description, and only in conjunction with non-Siemens equipment and
components recommended by Siemens.
Correct transport, storage, installation and assembly, as well as careful operation and
maintenance, are required to ensure that the product operates safely and without faults.
EU note: Commissioning is absolutely prohibited until it has been ensured that the machine
in which the component described here is to be installed complies with the stipulations of
the Directive 2006/42/EC.
2.3
Current information about operational safety
Important note for maintaining operational safety of your system
WARNING
Hazardous Voltage
Can Cause Death, Serious Injury, or Property Damage.
Please take note of our latest information.
Systems with safety-related characteristics are subject to special operational safety
requirements on the part of the operator. The supplier is also obliged to comply with special
product monitoring measures. For this reason, we publish a special newsletter containing
information on product developments and features that are (or could be) relevant to
operation of safety-related systems. By subscribing to the appropriate newsletter, you will
ensure that you are always up-to-date and able to make changes to your system, when
necessary:
SIEMENS newsletter (http://www.industry.siemens.com/newsletter)
Register under "Products and Solutions” for the following newsletter:
•Industrial Controls - SIRIUS News (en)
•Safety Integrated Newsletter

Product-specific safety information
2.4 Declaration of conformity
SIRIUS 3SK1 safety relays
Manual, 06/2018, A5E02526190021A/RS-AD/004 19
2.4
Declaration of conformity
The manufacturer declares that the safety components of the SIRIUS 3SK1 series in the
designs marketed by us comply with the applicable basic safety and health requirements of
the EC Directives* stated (including amendments) and that the stated standards* were
applied in their design and construction.
* You can download the complete EC Declaration of Conformity as a PDF.

Product-specific safety information
2.4 Declaration of conformity
SIRIUS 3SK1 safety relays
20 Manual, 06/2018, A5E02526190021A/RS-AD/004