{"schemaVersion":"matrix-product-facts/v1","identity":{"mpn":"6ES7151-7FA21-0AB0","brand":"Siemens","brandSlug":"siemens","productSlug":"6ES7151-7FA21-0AB0","canonicalUrl":"https://aoctrl.com/siemens/6ES7151-7FA21-0AB0","factsUrl":"https://aoctrl.com/api/mcp/products/6ES7151-7FA21-0AB0","rawCanonicalId":null},"summary":{"shortDescription":"Siemens IM151-7 F-CPU, 6ES7151-7FA21-0AB0, fail-safe CPU for ET 200S, 192 kB, Profibus DP DPV1, RS 485, isolated.","salesMarkdown":"## Fail-safe CPU for ET 200S with 192 kB The Siemens 6ES7151-7FA21-0AB0 is an IM151-7 F-CPU — a fail-safe CPU module for the ET 200S distributed I/O system. It integrates 192 kbyte of work memory and handles 244 byte each of process input and output data, making it the brains of a safety-oriented remote rack. This CPU communicates over Profibus DP with DPV1 extensions, using an isolated RS 485 interface. It supports routing, alarms, and forcing, and can serve as a Profibus DP slave but not as a client. ## Programming languages and memory backup Programmable in LAD, FBD, STL, and optionally SCL, CFC, GRAPH, and HiGraph. The CPU retains program data and retentive variables across power cycles, but must be restarted after each restart. Backup time is 6 weeks at 40 °C ambient. The retentive memory covers inputs, outputs, memory bits, data blocks, timers, and counters. The I2t rating is 0.09 A²·s — relevant for sizing the power supply and protecting the module's internal electronics against short-circuit energy. The module is not expandable and does not support MPI or TCP/IP. Its width is 60 mm for the CPU body, with the DP master interface adding 35 mm. Height is 119.5 mm, depth 75 mm — fits standard ET 200S rail spacing.","metaTitle":"Siemens 6ES7151-7FA21-0AB0 IM151-7 F-CPU, 192 kB","metaDescription":"Siemens 6ES7151-7FA21-0AB0 IM151-7 F-CPU PLC module. 192 kB integrated memory, 244 byte I/O, RS 485, DPV1, isolated. Sourced to order against RFQ.","metaKeywords":null},"attributes":{"series":null,"packageCase":null,"mountingType":null,"rohsStatus":null,"productStatus":null,"categoryPath":["PLC Communication Modules"],"specifications":{"CFC":"Yes; Optional","FBD":"Yes","I2t":"0.09 A²·s","LAD":"Yes","MPI":"No","SCL":"Yes; Optional","STL":"Yes","DPV1":"Yes","Type":"SFB","Depth":"75 mm","GRAPH":"Yes; Optional","Width":"60 mm; DP master module: 35 mm","Alarms":"Yes","Height":"119.5 mm","Inputs":"244 byte","Number":"1","Preset":"10","RS 485":"Yes","TCP/IP":"No","Forcing":"Yes","Outputs":"244 byte","Overall":"12","Present":"Yes","Routing":"Yes","GSD file":"The latest GSD file is available on the Internet (http://www.siemens.com/profibus-gsd)","Isolated":"Yes","As Client":"No","As Server":"Yes","HiGraph®":"Yes; Optional","Retentive":"Yes; Must be restarted at each restart","Supported":"Yes","Variables":"Inputs, outputs, memory bits, DB, times, counters","Adjustable":"Yes","Expandable":"No","Integrated":"192 kbyte","Size, max.":"256 byte","Backup time":"6 wk; At 40 °C ambient temperature, typically","Command set":"see instruction list","Granularity":"1 h","Lower Limit":"1 ms","STEP 7 Lite":"No","SYNC/FREEZE":"Yes","Single step":"Yes","Upper Limit":"6 000 ms","Equidistance":"Yes","Inputs, max.":"244 byte","Number, max.":"See S7-300 operation list","Status block":"Yes; Up to 2 simultaneously","in AS, slave":"No","to DP, slave":"Yes","Outputs, max.":"244 byte","Plug-in (MMC)":"Yes","in AS, master":"No","to DP, master":"Yes; With DP slave only slave clock","to MPI, slave":"Yes","Interface type":"External interface via master module 6ES7138-4HA00-0AB0","Nesting levels":"8","to MPI, master":"Yes","Can Be Read Out":"Yes","Inputs, default":"128 byte","Range of values":"0 to 2^31 hours (when using SFC 101)","Weight, approx.":"200 g; DP master module: Approx. 100 g","lifecycle_stage":"current","Block encryption":"Yes; With S7 block Privacy","Firmware version":"V3.3","Isochronous mode":"No","Of Which Central":"124","Outputs, default":"128 byte","Power loss, typ.":"4.2 W","Rated value (DC)":"24 V","S7 communication":"Yes; Only server, configured on one side","PROFIBUS DP slave":"No","Address area, max.":"32","Forcing, variables":"Inputs, outputs","Inputs, adjustable":"2 048 byte","PROFIBUS DP master":"Yes","Per Priority Class":"16","Retentivity preset":"Yes","Usable For Routing":"4; As slave only with active interface, with IM 151-7 CPU as DP master","Configuration rules":"max. 63 peripheral modules per station; station width < 1 m or < 2 m; max. 10 A per load group (power module); master interface module on right next to IM 151-7 CPU (X2 interface)","Data record routing":"Yes; With DP master module","Interfaces/bus type":"1x PROFIBUS DP","Number/Number range":"0","Outputs, adjustable":"2 048 byte","PG/OP communication":"Yes","Plug-in (MMC), max.":"8 Mbyte","Programming package":"as of STEP 7 V5.5 + SP1 or as of V5.2 + SP1 + HSP 219 + Distributed Safety or as of STEP 7 TIA Portal V11","Diagnostics function":"Yes","Group error SF (red)":"Yes","HW functional status":"01","Inrush current, typ.":"1.8 A","Isolation tested with":"500 V DC","Number of breakpoints":"4","Number of startup OBs":"1; OB 100","Retentivity available":"Yes; MB 0 to MB 255","Retentivity adjustable":"Yes; via non-retain property on DB","S7 basic communication":"Yes; I blocks only","System functions (SFC)":"see instruction list","Deviation per day, max.":"10 s; Typ.: 2 s","IP degree of protection":"IP20","Number of entries, max.":"500","Status/control variable":"Yes","Transmission rate, max.":"12 Mbit/s","User data per job, max.":"See online help of STEP 7 (shared parameters of the SFBs/FBs and of the SFCs/FCs of S7 Communication)","For Bit Operations, Typ.":"0.06 µs","Number of DPV1 alarm OBs":"3; OB 55, 56, 57","Number of GD loops, max.":"8","Number of blocks (total)":"1 024; (DBs, FCs, FBs); the maximum number of loadable blocks can be reduced by the MMC used.","Number of clock memories":"8; 1 memory byte","Number of free cycle OBs":"1; OB 1","Number of time alarm OBs":"1; OB 10","Of Which Powerfail-Proof":"100; Only the last 100 entries are retained","Per Priority Class, Max.":"32 kbyte; Max. 2048 bytes per block","Size of GD packets, max.":"22 byte","For Word Operations, Typ.":"0.12 µs","Global data communication":"No","Number of DP slaves, max.":"32; Per station","Number of delay alarm OBs":"2; OB 20, 21","Number of variables, max.":"10","Point-to-point connection":"No","Automatic Baud Rate Search":"Yes; only with passive interface","Hardware clock (real-time)":"Yes","Number of GD packets, max.":"8","Number of process alarm OBs":"1; OB 40","Process diagnostic messages":"Yes; ALARM_S, ALARM_SC, ALARM_SQ, ALARM_D, ALARM_DQ","Reverse polarity protection":"Yes; against destruction","S7 communication, as client":"No","S7 communication, as server":"Yes","usable for OP communication":"11","usable for PG communication":"11","Retentive And Synchronizable":"Yes","System function blocks (SFB)":"see instruction list","Length of mounting rail, max.":"Station width: ≤ 1 m or < 2 m","additional within an error OB":"4","from supply voltage 1L+, max.":"320 mA; 410 mA with DP master module","reserved for OP communication":"1","reserved for PG communication":"1","Cycle Monitoring Time / Preset":"150 ms","Number of cyclic interrupt OBs":"4; OB 32, 33, 34, 35","Number of synchronous error OBs":"2; OB 121, 122","Of Which Status Variables, Max.":"30","For Fixed Point Arithmetic, Typ.":"0.16 µs","Number of asynchronous error OBs":"6; OB 80, 82, 83 (for centralized I/O only, not for distributed I/O), 85, 86, 87","Of Which Control Variables, Max.":"14","User data per address area, max.":"32 byte; Up to max. size of the transfer memory","for backplane bus (5 V DC), max.":"700 mA","usable for S7 basic communication":"10","Number of modules per system, max.":"63; Centralized","For Floating Point Arithmetic, Typ.":"0.59 µs","permissible range, lower limit (DC)":"19.2 V","permissible range, upper limit (DC)":"28.8 V","reserved for S7 basic communication":"0","Activation/deactivation of DP slaves":"Yes","Number of GD packets, receiver, max.":"8","Output current of the interface, max.":"No","adjustable for OP communication, max.":"11","adjustable for OP communication, min.":"1","adjustable for PG communication, max.":"11","adjustable for PG communication, min.":"1","Number of GD packets, transmitter, max.":"8","Number of entries readable in RUN, max.":"499","Behavior of the clock following POWER-ON":"Clock continues running after POWER OFF","Mains/voltage failure stored energy time":"5 ms","Monitoring 24 V voltage supply ON (green)":"Yes","Number of mounting rails that can be used":"1","simultaneously active Alarm-S blocks, max.":"300","User program protection/password protection":"Yes","adjustable for S7 basic communication, max.":"10","adjustable for S7 basic communication, min.":"0","Size of GD packet (of which consistent), max.":"22 byte","User data per job (of which consistent), max.":"See online help of STEP 7 (shared parameters of the SFBs/FBs and of the SFCs/FCs of S7 Communication)","Direct data exchange (slave-to-slave communication)":"Yes","Number of login stations for message functions, max.":"12; Depending on the configured connections for PG/OP and S7 basic communication","between PROFIBUS DP and all other circuit components":"Yes","Data management on MMC (after last programming), min.":"10 a","Behavior of the clock following expiry of backup period":"the clock continues at the time of day it had when power was switched off","Retentive data area (incl. timers, counters, flags), max.":"64 kbyte","External Protection For Power Supply Lines (Recommendation)":"2 A min.","Number of DP slaves that can be simultaneously activated/deactivated, max.":"8"}},"commercial":{"minOrderQty":null,"leadTime":null,"referencePrice":"$2,271.00 – $4,155.57","priceTiers":null},"links":{"datasheetUrl":"https://cdn.aoctrl.com/599fb3d3d8592ec955b0ddbf0a810439.pdf","sourceUrl":"https://support.industry.siemens.com/webbackend/api/ProductSupport/TechnicalData?language=en&region=cn&productId=514598&mlfb=6ES7151-7FA21-0AB0","alternativesUrl":"https://aoctrl.com/api/mcp/products/6ES7151-7FA21-0AB0/alternatives.json"},"ai":{"faq":[{"question":"What is the 6ES7151-7FA21-0AB0 used for?","answer":"This IM151-7 F-CPU is a fail-safe CPU for the ET 200S distributed I/O system. It runs safety-oriented control logic over Profibus DP, handling up to 244 byte each of inputs and outputs with 192 kB of integrated program memory."},{"question":"Does the 6ES7151-7FA21-0AB0 require a battery?","answer":"No battery is needed. The CPU retains program and retentive data for up to 6 weeks at 40 °C ambient via a capacitor-based backup."},{"question":"How can I order the 6ES7151-7FA21-0AB0 or check stock?","answer":"This module is sourced to order against your RFQ. Availability and pricing are confirmed at quote time."}],"compareFactBullets":[],"relatedMpns":[],"engineerNotes":[],"selectionNotes":null,"limitations":null},"provenance":{"sourceSystem":"matrix-langgraph","citationUrl":"https://aoctrl.com/siemens/6ES7151-7FA21-0AB0","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/6ES7151-7FA21-0AB0 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}}