3SK1121-2AB40

**3SK1121-2AB40** 

**Data sheet** 

SIRIUS safety relay Basic unit Advanced series Relay enabling circuits 3 NO contacts plus Relay signaling circuit 1 NC contact Us = 24 V DC Spring-type terminal (push-in) 

|SIRIUS safety relay Basic unit Advanced series Relay enabling circuits 3 NO<br>contacts plus Relay signaling circuit 1 NC contact Us = 24 V DC Spring-type<br>terminal (push-in)<br>**product brand name**<br>SIRIUS<br>**product category**<br>Safetyrelays<br>**product designation**<br>safetyrelays<br>**design of theproduct**<br>Relayenablingcircuits<br>**product type designation**<br>3SK1<br>**product line**<br>Advanced basic unit<br>**Product Function**<br>**product function parameterizable**<br>sensor floating / sensor non-floating, monitored start-up / automatic start, 1-<br>channel / 2-channel sensor connection, cross-circuit detection, startup testing,<br>antivalent sensors, 2-hand switches<br>**product function**<br>● automatic start<br>Yes<br>● light barrier monitoring<br>Yes<br>●protective door monitoring<br>Yes<br>● magneticallyoperated switch monitoringNC-NO<br>Yes<br>● magneticallyoperated switch monitoringNC-NC<br>Yes<br>● laser scanner monitoring<br>Yes<br>● light arraymonitoring<br>Yes<br>● EMERGENCY OFF function<br>Yes<br>● monitored start-up<br>Yes<br>●pressure-sensitive mat monitoring<br>No<br>**product feature cross-circuit-proof**<br>Yes<br>**suitability for interactionpress control**<br>Yes<br>**suitability for operation device connector 3ZY12**<br>Yes<br>**suitability for use**<br>● monitoringof floatingsensors<br>Yes<br>● monitoringof non-floatingsensors<br>Yes<br>●position switch monitoring<br>Yes<br>● EMERGENCY-OFF circuit monitoring<br>Yes<br>● opto-electronicprotection device monitoring<br>Yes<br>● magneticallyoperated switch monitoring<br>Yes<br>● safetyswitch<br>Yes<br>● safety-related circuits<br>Yes<br>**General technical data**<br>certificate of suitabilityUL approval<br>Yes<br>**power loss[W] maximum**<br>2 W<br>**insulation voltage rated value**<br>300 V<br>**degree ofpollution**<br>3<br>**overvoltage category**<br>3<br>**surge voltage resistance rated value**<br>4 000 V|SIRIUS safety relay Basic unit Advanced series Relay enabling circuits 3 NO<br>contacts plus Relay signaling circuit 1 NC contact Us = 24 V DC Spring-type<br>terminal (push-in)||
|---|---|---|
||SIRIUS||
||Safetyrelays||
||safetyrelays||
||Relayenablingcircuits||
||3SK1||
||Advanced basic unit||
||Yes||
||2 W||
||300 V||
||3||
||3||
||4 000 V||



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|protection class IP of the enclosure|IP20|
|---|---|
|**shock resistance**|10g/ 11 ms|
|**vibration resistance according to IEC 60068-2-6**|5 ... 500 Hz: 0.75 mm|
|**operating frequency maximum**|360 1/h|
|**reference code according to IEC 81346-2**|F|
|**Substance Prohibitance(day/month/year)**|11/05/2012|
|**SVHC substance name**|Lead CAS-No. 7439-92-1<br>Lead monoxide (lead oxide) CAS-No. 1317-36-8<br>2-methyl-1-(4-methylthiophenyl)-2-morpholinopropan-1-one CAS-No. 71868-<br>10-5<br>Melamine CAS-No. 108-78-1<br>6,6'-di-tert-butyl-2,2'-methylenedi-p-cresol CAS-No. 119-47-1<br>4,4'-isopropylidenediphenol(Bisphenol A, BPA)CAS-No. 80-05-7|
|**Net Weight**|0.245 kg|
|**Ambient conditions**||
|installation altitude at height above sea level maximum|4 000 m|
|● note|Derating, see Product Notification 109792701|
|**ambient temperature**||
|● duringoperation|-25 ... +60 °C|
|● duringstorage|-40 ... +80 °C|
|relative humidityduringoperation|10 ... 95 %|
|air pressure accordingto SN 31205|900 ... 1 060 hPa|
|**Electromagnetic compatibility**||
|**installation environment regarding EMC**|This product is suitable for Class A environments only. In household<br>environments, this device can cause unwanted radio interference. The user is<br>required to implement appropriate measures in this case.|
|**EMC emitted interference**|IEC 60947-5-1, Class A|
|**Safety related data**||
|product function suitable for safetyfunction|Yes|
|**safe state**|Safetyoutputs switched off|
|**test wear-related service life necessary**|Yes|
|**function test interval maximum**|1 a|
|**diagnostics test interval by internal test function maximum**|600 s|
|**stop category according to IEC 60204-1**|0|
|IEC 62061||
|SIL Claim Limit(subsystem)accordingto EN 62061|3|
|**Safety Integrity Level(SIL)**||
|**● according to IEC 62061**|SIL 3|
|● at single-channel evaluation accordingto IEC 62061|1|
|● at 2-channel evaluation accordingto IEC 62061|3|
|**PFHD with high demand rate according to IEC 62061**|0,0000000025|
|ISO 13849||
|categoryaccordingto EN ISO 13849-1|4|
|**performance level(PL)**||
|**● according to ISO 13849-1**|PL e|
|● at single-channel evaluation accordingto ISO 13849-1|c|
|● at 2-channel evaluation accordingto ISO 13849-1|e|
|**category**||
|**● according to ISO 13849-1**|4|
|● at 2-channel evaluation accordingto ISO 13849-1|4|
|**overdimensioning according to ISO 13849-2 necessary**|No|
|IEC 61508||
|**Safety Integrity Level(SIL)**||
|● accordingto IEC 61508|3|
|● at single-channel evaluation accordingto IEC 61508|1|
|● at 2-channel evaluation accordingto IEC 61508|3|
|**safety device type according to IEC 61508-2**|Type B|
|**PFHD with high demand rate according to IEC 61508**|0,0000000025|
|**Safe failure fraction(SFF)**|99 %|
|**hardware fault tolerance**||
|● according to IEC 61508|1|



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|● at single-channel evaluation accordingto IEC 61508|0|
|---|---|
|● at 2-channel evaluation accordingto IEC 61508|1|
|**T1 value**||
|● of service life accordingto IEC 61508|20 a|
|● for proof test interval or service life according to IEC<br>61508|20 a|
|Electrical Safety||
|**touch protection against electrical shock**|finger-safe|
|**Short-circuit protection**||
|**design of the fuse link**||
|● for short-circuit protection of the NO contacts of the relay<br>outputs required|gL/gG: 6A or circuit breaker type A: 3A or circuit breaker type B: 2A or circuit<br>breaker type C: 1A|
|● for short circuit protection of the NC contacts of the relay<br>outputs required|Diazed or Neozed fuses, operating class gL/gG: 6 A or MCB type A: 2 A or<br>MCB type B: 2 A or MCB type C: 1 A|
|**Inputs**||
|**design of input**||
|● cascadinginput/functional switching|Yes|
|● feedback input|Yes|
|● start input|Yes|
|pulse duration of the sensor input minimum|75 ms|
|number of sensor inputs 1-channel or 2-channel|1|
|**Outputs**||
|**number of outputs as contact-affected switching element**||
|● as NC contact||
|— for signalingfunction instantaneous contact|1|
|● as NO contact||
|— safety-related instantaneous contact|3|
|— safety-related delayed switching|0|
|**mechanical service life(operating cycles) typical**|10 000 000|
|**thermal current of the switching element with contacts**<br>**maximum**|5 A|
|**switching capacity current of the NO contacts of the relay**<br>**outputs at DC-13**||
|● at 24 V|5 A|
|● at 115 V|0.2 A|
|● at 230 V|0.1 A|
|**switching capacity current of the NO contacts of the relay**<br>**outputs at AC-15**||
|● at 115 V|5 A|
|● at 230 V|5 A|
|**switching capacity current of the NC contacts of the relay**<br>**outputs at DC-13**||
|● at 24 V|1 A|
|● at 115 V|0.2 A|
|● at 230 V|0.1 A|
|**switching capacity current of the NC contacts of the relay**<br>**outputs at AC-15**||
|● at 24 V|2 A|
|● at 115 V|1.5 A|
|● at 230 V|1.5 A|
|**total current maximum**|12 A|
|**operational current at 17 V minimum**|5 mA|
|**Times**||
|**make time with automatic start**||
|● at DC maximum|110 ms|
|**make time with automatic start afterpower failure**||
|● typical|6 500 ms|
|● maximum|6 500 ms|
|**make time with monitored start**||
|● maximum|110 ms|
|**backslide delay time after opening of the safety circuits**|40 ms|



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|**typical**|**typical**||
|---|---|---|
|**backslide delay time in the event ofpower failure**|||
|● typical||30 ms|
|● maximum||50 ms|
|**recovery time after opening of the safety circuits typical**||30 ms|
|**recovery time afterpower failure typical**||6.5 s|
|**pulse duration**|||
|● of the ON pushbutton input minimum||0.15 s|
|**Control circuit/ Control**<br>~~et~~|||
|**type of voltage of the control supply voltage**<br>~~et~~||DC<br>~~et~~|
|**control supply voltage at DC rated value**||24 V|
|**operating range factor control supply voltage rated value of**<br>**magnet coil at DC**|||
|● initial value||0.8|
|● full-scale value||1.2|
|**Installation/ mounting/ dimensions**<br>~~a~~|||
|**mounting position**<br>~~a~~||any|
|**fastening method**||screw and snap-on mounting|
|**height**||100 mm|
|**width**||22.5 mm|
|**depth**||121.5 mm|
|**required spacing**|||
|● forgrounded parts at the side||5 mm|
|**Connections/ Terminals**<br>~~re~~|||
|**type of electrical connection**<br>~~re~~||spring-loaded terminal(push-in)<br>~~re~~|
|**wire length**|||
|● with Cu 1.5 mm² and 150 nF/km per sensor circuit<br>maximum||4 000 m|
|**type of connectable conductor cross-sections**|||
|● solid||1x(0.5 ... 1.5 mm²), 2x(0.5 ... 1.5 mm²)|
|● finelystranded with core endprocessing||1x(0.5 ... 1.0 mm²), 2x(0.5 ... 1.0 mm²)|
|● finelystranded without core endprocessing||1x(0.5 ... 1.5 mm²), 2x(0.5 ... 1.5 mm²)|
|● for AWG cables solid||1x(20 ... 16), 2x(20 ... 16)|
|● for AWG cables stranded||1x(20 ... 16), 2x(20 ... 16)|
|**type of electrical connection plug-in socket**||No|
|**Approvals Certificates**<br>~~ee~~|||
|**Environment**<br>~~ee~~|**General Product Approval**<br>~~ee~~||



**Railway** 

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Confirmation 

**Further information Information on the packaging** https://support.industry.siemens.com/cs/ww/en/view/109813875 **Information for data generation and storage** https://support.industry.siemens.com/cs/ww/en/view/109995012 **Information- and Downloadcenter (Catalogs, Brochures,…)** https://www.siemens.com/ic10 **Industry Mall (Online ordering system)** https://mall.industry.siemens.com/mall/en/en/Catalog/product?mlfb=3SK1121-2AB40 **Cax online generator** https://support.automation.siemens.com/WW/CAXorder/default.aspx?lang=en&mlfb=3SK1121-2AB40 **Service&Support (Manuals, Certificates, Characteristics, FAQs,...)** https://support.industry.siemens.com/cs/ww/en/ps/3SK1121-2AB40 **Image database (product images, 2D dimension drawings, 3D models, device circuit diagrams, EPLAN macros, ...)** https://www.automation.siemens.com/bilddb/cax_de.aspx?mlfb=3SK1121-2AB40&lang=en 

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