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3SK1112-1BB40
Safety Relay, 24 VDC, SIRIUS Series, DIN Rail, 2 A, Screw
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- Manufacturer: SIEMENS
- Product type: Safety Relays
- Product Range: SIRIUS 3SK1 Series
| Delivery and price | |
|---|---|
| Units per pack | 1 |
| Price | 214.02 € |
| Current stock | 10+ |
| Lead time | 30 days |
**3SK1112-1BB40**
**Data sheet**
SIRIUS safety relay Basic unit Standard series electronic enabling circuits 2 enabling circuits plus 1 signaling circuit Us = 24 V DC screw terminal
|{<br>f|SIRIUS safety relay Basic unit Standard series electronic enabling circuits 2<br>enabling circuits plus 1 signaling circuit Us = 24 V DC screw terminal|
|---|---|
|**product brand name**|SIRIUS|
|**product category**|Safetyrelays|
|**product designation**|safetyrelays|
|**design of theproduct**|Solid-state enablingcircuits|
|**product type designation**|3SK1|
|**product line**|Standard basic unit|
|**Product Function**||
|**product function parameterizable**|sensor floating / sensor non-floating, monitored start-up / automatic start, 1-<br>channel / 2-channel sensor connection, cross-circuit detection, startuptesting|
|**product function**||
|● automatic start|Yes|
|● light barrier monitoring|Yes|
|●protective door monitoring|Yes|
|● magneticallyoperated switch monitoringNC-NO|No|
|● magneticallyoperated switch monitoringNC-NC|Yes|
|● laser scanner monitoring|Yes|
|● light arraymonitoring|Yes|
|● EMERGENCY OFF function|Yes|
|● monitored start-up|Yes|
|●pressure-sensitive mat monitoring|No|
|**product feature cross-circuit-proof**|Yes|
|**suitability for interactionpress control**|No|
|**suitability for operation device connector 3ZY12**|No|
|**suitability for use**||
|● monitoringof floatingsensors|Yes|
|● monitoringof non-floatingsensors|Yes|
|●position switch monitoring|Yes|
|● EMERGENCY-OFF circuit monitoring|Yes|
|● opto-electronicprotection device monitoring|Yes|
|● magneticallyoperated switch monitoring|Yes|
|● safetyswitch|Yes|
|● safety-related circuits|Yes|
|**General technical data**||
|certificate of suitabilityUL approval|Yes|
|**power loss[W] maximum**|2 W|
|**insulation voltage rated value**|50 V|
|**degree ofpollution**|3|
|**overvoltage category**|3|
|**surge voltage resistance rated value**|800 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**|2 000 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|
|**Net Weight**|0.164 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**|No|
|**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**|0,0000000010|
|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**|0,0000000010|
|**Safe failure fraction(SFF)**|99 %|
|**hardware fault tolerance**||
|● accordingto IEC 61508|1|
|● at single-channel evaluation accordingto IEC 61508|0|
|● at 2-channel evaluation according to IEC 61508|1|
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|**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|not required|
|**Inputs**||
|**design of input**||
|● cascadinginput/functional switching|Yes|
|● feedback input|Yes|
|● start input|Yes|
|pulse duration of the sensor input minimum|60 ms|
|number of sensor inputs 1-channel or 2-channel|1|
|**Outputs**||
|**number of outputs as contact-affected switching element**||
|● as NO contact||
|— safety-related instantaneous contact|0|
|— safety-related delayed switching|0|
|**number of outputs as contact-less semiconductor**<br>**switching element**||
|● for signalingfunction||
|— instantaneous contact|1|
|● safety-related||
|— delayed switching|0|
|— instantaneous contact|2|
|switching capacity current of semiconductor outputs at DC-13 at<br>24 V|2 A|
|**Times**||
|**make time with automatic start**||
|● at DC maximum|85 ms|
|**make time with automatic start afterpower failure**||
|● typical|6 500 ms|
|● maximum|6 500 ms|
|**make time with monitored start**||
|● maximum|85 ms|
|**backslide delay time after opening of the safety circuits**<br>**typical**|40 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**||
|**type of voltage of the control supply voltage**|DC|
|**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**||
|**mounting position**|any|
|**fastening method**|screw and snap-on mounting|
|**height**|100 mm|
|**width**|22.5 mm|
|**depth**|91.5 mm|
|**required spacing**||
|● for grounded parts at the side|5 mm|
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Subject to change without notice © Copyright Siemens
5/29/2026
~~re~~ **Connections/ Terminals type of electrical connection** screw terminal **wire length** ● with Cu 1.5 mm² and 150 nF/km per sensor circuit 4 000 m maximum **type of connectable conductor cross-sections** ● solid 1x (0.5 ... 2.5 mm²), 2x (1.0 ... 1.5 mm²) ● finely stranded with core end processing 1x (0.5 ... 2.5 mm²), 2x (0.5 ... 1.0 mm²) ● for AWG cables solid 1x (20 ... 14), 2x (18 ... 16) ● for AWG cables stranded 1x (20 ... 16), 2x (20 ... 16) **type of electrical connection plug-in socket** No ~~ee~~ **Approvals Certificates Environment General Product Approval** Environmental Confirmations **General Product ApEMV Functional Saftey Test Certificates Maritime application proval** - - Type Examination Cer Type Test Certific tificate ates/Test Report UK ~~——_ =~~ **Maritime application other** Confirmation Confirmation - **Railway** Confirmation ~~e~~ **Further information** ~~e~~ **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=3SK1112-1BB40 **Cax online generator** https://support.automation.siemens.com/WW/CAXorder/default.aspx?lang=en&mlfb=3SK1112-1BB40 **Service&Support (Manuals, Certificates, Characteristics, FAQs,...)** https://support.industry.siemens.com/cs/ww/en/ps/3SK1112-1BB40 **Image database (product images, 2D dimension drawings, 3D models, device circuit diagrams, EPLAN macros, ...)** https://www.automation.siemens.com/bilddb/cax_de.aspx?mlfb=3SK1112-1BB40&lang=en
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-K<br>1 | Autostart / Monitored Start Logic<br>2 | Cross fault detection OFF / ON<br>3 | 2 single-ch. sensors / 1 double-ch. sensor<br>4 | Startup Test yes / no<br>SET / RESET<br>A1+ INK T1 IN1 T2 IN2 INF INS<br>1 2<br>Q Q<br>A2- QM1<br>**----- End of picture text -----**<br>
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Updated at April 23, 2026
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