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Entry type: Application example Entry ID: 82526134, Entry date: 08/28/2014

SINAMICS S120: Application example for the "Safely Limited Position (SLP)" function and the "Retraction" block using the EPOS function

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In this example, safety functions SS1E and SLP should be controlled in conjunction with the EPOS function of the SINAMICS S120. Safety function SS1E becomes active when Emergency Stop pushbutton -S1 is pressed. The drive is externally braked until standstill is reached. It then goes into the STO state.
Based on safe actual value sensing, the drive position values are available in a safety-related form. When the "Safely Limited Position (SLP)" safety function is active, the drive cannot exit a position range that has been configured by the user. When the limit values are reached, the drive is stopped with the configured stop response. In order to be able to traverse the drive from a non-permissible position range, safety function SDI and traversing the drive in the jog mode are also configured. The drive can be traversed back into the permissible position range using the "Retraction" block integrated in the safety program in the F-CPU. In this particular example, the safety function is controlled via PROFIsafe with PROFINET.


Controlling safety functions SS1E and SLP via PROFIsafe with PROFINET – as well as using the basic positioner (EPOS) – for a SINAMICS S120 drive is demonstrated using this application example.
The drive line-up in the booksize format comprises an infeed and a Double Motor Module (DMM). Position and motor control are realized using a CU320-2 PN Control Unit. This involves hardware that is installed in the SINAMICS S120 demonstration cases. The servomotor is controlled using the Double Motor Module. A Smart Line Module (SLM) is used as infeed.
The safety-relevant signals are sensed using fail-safe digital input modules, logically processed in the F-CPU. The F-CPU sends the fail-safe data to the drive via the PROFIsafe telegram 31, where it controls the safety functions.



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