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Entry type: Application example Entry ID: 101167223, Entry date: 02/08/2019

SINAMICS S: Failsafe SIMATIC S7-300/400/1500 function blocks for storage and retrieval machines with S120

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The function of fail-safe blocks for storage and retrieval machines is to guarantee plant and system safety (safety of persons and machines) up to safety class SIL 2 (DIN EN 62061) or to Performance Level d (EN ISO 13849-1).

The safety function includes position monitoring, velocity monitoring at the end of the traversing range (warehouses without any intermediate buffer), brake test, brake ramp monitoring, overload detection, slack cable detection and several others.

The ASRM Failsafe library has been developed to structure a modular safety program, adapted to specific storage and retrieval machines. The blocks of the library are failsafe function and data blocks in the SIMATIC S7 Distributed Safety or SIMATIC STEP 7 Safety Advanced programming environment. They are certified by TÜV SÜD (German Technical Inspectorate) – and can run on failsafe controllers of the SIMATIC S7-F 300, 400 and 1500 series.


The ASRM Failsafe library is now available in version 3.0 and can be used with TIA V15 or newer. 


- The performance of the blocks has been increased enormously.

- The availability of the system has been improved

- The commissioning for a bufferless/buffer-reduced warehouse has been simplified

The following essential components are necessary when using fail-safe function blocks for storage and retrieval machines:

  • Failsafe SIMATIC S7-300 or -400 controller – Distributed Safety/Safety Advanced from V13 onwards
  • Fail-safe SIMATIC S7-1500 controller – Safety Advanced from V13 SP1 onwards

  • SINAMICS S120 inverter with CU320-2 (from firmware release 4.6), called SINAMICS S120 in the following, with encoder connected to
            o SMC20/SMC30
            o or via DRIVE-CLiQ
  • F-DO module to control the brakes
  • F-AI module or comparable safety-related signal source for load measurement for overload/slack cable detection
  • External mechanical brake and/or motor holding brake

The hardware design can look like this for example:

An overview of the implemented safety functions (these are also applicable for systems with inherent slip):

  • Generation of a safety-related position actual value
  • Generation of a safety-related velocity actual value
  • Safety-related monitoring of end positions of a traversing range with retraction logic
  • Safety-related monitoring of the velocity when approaching to the end positions of a traversing range in order to be able to implement a warehouse without intermediate buffer
  • Safe brake ramp monitoring
  • Safe brake test
  • Safety-related overload and slack cable detection
  • Minimum-maximum evaluation

When using a failsafe SIMATIC S7 controller the usual standard functionality is also available just as before. A separate controller is not required.

The function blocks are tested in accordance with the following standards:

  • DIN EN 62061: 2005 (up to SIL 2)
  • DIN EN ISO 13849-1: 2008 (up to PL d)
  • DIN EN ISO 13849-2: 2013 (up to PL d)
  • DIN EN 528 "Rail dependent storage and retrieval equipment – Safety requirements"


  • Significantly lower engineering costs by using parameterizable function blocks
  • Significantly lower costs for machine acceptance by using certified function blocks
  • The full traversing range can be used without requiring mechanical buffers
  • Fewer number of hardware components and lower cabling costs

For the SIMATIC S7-300/400 controllers the package contains the block library in both the SIMATIC S7 Distributed Safety and SIMATIC STEP 7 Safety Advanced V13 programming environments.
For the SINAMITC S7-1500 controllers the package contains the block library in STEP 7 Safety Advanced V13 SP1.
In addition the associated manual, and Excel tables for simpler configuration of the blocks and the TÜV certificate (German Technical Inspectorate) are part of the package.

The blocks are provided at no charge if end user data are provided.

For more information and demonstration videos look here: Info & Demonstration

  Manual V1.0  06/2014 (1,9 MB) 
  Certificate V1.0  06/2014 (593,3 KB) 

  Manual V2.0  04/2016 (2,2 MB) 
  Certificate V2.0  04/2016 (689,4 KB) 
  FAQ notes on how to handle faults in the position sensing system 07/2016 (1,5 MB)

  Manual V2.1 04/2017 (3,0 MB)
  Certificate V2.1 04/2017 (624,9 KB)

  Manual V3.0 01/2019 (3,0 MB)
  Certificate V3.0 01/2019 (776,6 KB) 

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