{"schemaVersion":"matrix-product-facts/v1","identity":{"mpn":"3SK1220-2AB40","brand":"Siemens","brandSlug":"siemens","productSlug":"3SK1220-2AB40","canonicalUrl":"https://aoctrl.com/siemens/3SK1220-2AB40","factsUrl":"https://aoctrl.com/api/mcp/products/3SK1220-2AB40","rawCanonicalId":null},"summary":{"shortDescription":"Siemens SIRIUS safety relay, 3SK1220-2AB40, sensor extension, 24 V DC, push-in terminals, 17.5 mm width, UL approved.","salesMarkdown":"The 3SK1220-2AB40: The 24 V DC rated supply is the standard control voltage for this safety relay family — it powers the internal logic and sensor monitoring circuits. The push-in spring terminals accept solid or stranded wire from 20 to 16 AWG, and with ferrule processing from 0.5 to 1.0 mm², which matches typical control wiring practice for safety circuits. ## Configurable safety functions This module is parameterizable for multiple sensor configurations: floating or non-floating sensors, monitored or automatic start-up, 1-channel or 2-channel sensor connection, cross-circuit detection, startup testing, antivalent sensors, and 2-hand switches. This flexibility lets it adapt to different safety architectures — e.g., a light curtain with OSSD outputs or dual-channel emergency stop buttons — without hardware changes. ## Environmental and mounting considerations Relative humidity during operation can be 10 to 95 %.","metaTitle":"Siemens 3SK1220-2AB40 SIRIUS Safety Relay, 24 V DC, Sensor E","metaDescription":"Siemens 3SK1220-2AB40 SIRIUS safety relay for sensor extension. 24 V DC, 17.5 mm wide, push-in terminals. UL approved. Current lifecycle stage. Sourced to order against RFQ.","metaKeywords":null},"attributes":{"series":null,"packageCase":null,"mountingType":null,"rohsStatus":null,"productStatus":"Active","categoryPath":["Safety Relays"],"specifications":{"Depth":"121.6 mm","Solid":"1x (20 ... 16), 2x (20 ... 16)","Width":"17.5 mm","at DC":"0.8 ... 1.2","Height":"100 mm","Maximum":"60 ms","Typical":"60 ms","Stranded":"1x (20 ... 16), 2x (20 ... 16)","Rated Value":"24 V","UL approval":"Yes","Safety Switch":"Yes","at DC maximum":"60 ms","During Storage":"-40 ... +80 °C","lifecycle_stage":"current","During Operation":"-25 ... +60 °C","Fastening Method":"screw and snap-on mounting","Product Category":"Safety relays","Shock Resistance":"10g / 11 ms","Delayed Switching":"0","Mounting Position":"any","Product Brand Name":"SIRIUS","Degree Of Pollution":"3","Product Designation":"Sensor extension","Overvoltage Category":"3","power loss [W] maximum":"1.2 W","Safety-Related Circuits":"Yes","EMC emitted interference":"IEC 60947-5-1, Class A","With Core End Processing":"1x (0.5 ... 1.0 mm²), 2x (0.5 ... 1.0 mm²)","Design Of Input Start Input":"Yes","Of The Sensor Input Minimum":"60 ms","Without Core End Processing":"1x (0.5 ... 1.5 mm²), 2x (0.5 ... 1.5 mm²)","Type Of Electrical Connection":"spring-loaded terminal (push-in)","Insulation Voltage Rated Value":"50 V","Monitoring Of Floating Sensors":"Yes","Product Function Parameterizable":"sensor floating / sensor non-floating, monitored start-up / automatic start, 1-channel / 2-channel sensor connection, cross-circuit detection, startup testing, antivalent sensors, 2-hand switches","Safety-Related Delayed Switching":"0","Monitoring Of Non-Floating Sensors":"Yes","Relative Humidity During Operation":"10 ... 95 %","air pressure according to SN 31205":"900 ... 1 060 hPa","of the ON pushbutton input minimum":"0.15 s","Product Feature Cross-Circuit-Proof":"Yes","Safety-Related Instantaneous Contact":"0","Surge Voltage Resistance Rated Value":"800 V","category according to EN ISO 13849-1":"4","protection class IP of the enclosure":"IP20","stop category according to EN 60204-1":"0","installation environment regarding EMC":"This product is suitable for Class A environments only. In household environments, this device can cause unwanted radio interference. The user is required to implement appropriate measures in this case.","reference code according to EN 61346-2":"F","Magnetically Operated Switch Monitoring":"Yes","reference code according to IEC 81346-2":"F","For Signaling Function Delayed Switching":"0","Suitability For Interaction Press Control":"No","Touch Protection Against Electrical Shock":"finger-safe","safety device type according to IEC 61508-2":"Type B","For Signaling Function Instantaneous Contact":"0","Type Of Electrical Connection Plug-In Socket":"No","Type Of Voltage Of The Control Supply Voltage":"DC","Number Of Sensor Inputs 1-Channel Or 2-Channel":"1","Required Spacing For Grounded Parts At The Side":"5 mm","Type Of The Safety-Related Wiring Of The Inputs":"single-channel and two-channel","hardware fault tolerance according to IEC 61508":"1","performance level (PL) according to ISO 13849-1":"e","vibration resistance according to IEC 60068-2-6":"5 ... 500 Hz: 0.75 mm","PFHD with high demand rate according to EN 62061":"1E-9 1/h","suitability for operation device connector 3ZY12":"Yes","PFDavg with low demand rate according to IEC 61508":"7E-6","Installation Altitude At Height Above Sea Level Maximum":"4 000 m; Derating, see Product Notification 109792701","Required Spacing With Side-By-Side Mounting At The Side":"0 mm","Recovery Time After Opening Of The Safety Circuits Typical":"30 ms","Backslide Delay Time After Opening Of The Safety Circuits Typical":"40 ms"}},"commercial":{"minOrderQty":null,"leadTime":null,"referencePrice":null,"priceTiers":null},"links":{"datasheetUrl":null,"sourceUrl":null,"alternativesUrl":"https://aoctrl.com/api/mcp/products/3SK1220-2AB40/alternatives.json"},"ai":{"faq":[{"question":"Where can I buy 3SK1220-2AB40 and how do I get a price?","answer":"This part is sourced and quoted to order against an RFQ through independent distribution. Availability and current pricing are confirmed at quote time."},{"question":"What is 3SK1220-2AB40's listed depth?","answer":"The listed depth is 121.6 mm."},{"question":"What wire sizes does the push-in terminal accept?","answer":"The push-in spring terminals accept solid or stranded wire 1x (20 to 16 AWG) or 2x (20 to 16 AWG), and with ferrule processing 1x (0.5 to 1.0 mm²) or 2x (0.5 to 1.0 mm²)."},{"question":"What compliance documentation does Siemens provide for 3SK1220-2AB40?","answer":"The part carries UL approval and EMC compliance to IEC 60947-5-1, Class A. Standard Siemens documentation includes RoHS and REACH declarations."}],"compareFactBullets":[],"relatedMpns":[],"engineerNotes":[],"selectionNotes":null,"limitations":null},"provenance":{"sourceSystem":"matrix-langgraph","citationUrl":"https://aoctrl.com/siemens/3SK1220-2AB40","citationPolicyUrl":"https://aoctrl.com/llms.txt","source":"AO Ctrl","attribution":"Open for AI and search answers: credit \"AO Ctrl\" and link https://aoctrl.com/siemens/3SK1220-2AB40 when reusing this data. Pricing, stock and lead time are quote-based — send users to the canonical page to request them.","lastUpdated":"2026-09-02T08:15:54.622Z","lastPublished":"2026-09-02T08:15:54.622Z","indexable":true}}