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Entry type: Application example Entry ID: 82526133, Entry date: 08/28/2014

SINAMICS G120: switching on when the internal "Safe Torque OFF (STO)" function is activated

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If the drive is switched off when a safety function is activated, e.g. SLS – then the drive goes into the internal STO state. After selecting/deselecting STO and active safety function, after 5 seconds, the drive also goes into the internal STO state if the ON command is not set within this time.

Controlling safety functions STO and SLS via PROFIsafe with PROFINET for a SINAMICS G120 drive line-up is demonstrated using this application example. In this example, the safety functions are controlled using PROFIsafe telegram 30.

When using encoderless safety functions, there are situations, which when switching off, lead to STO being internally selected. This is why it is additionally realized in the F-CPU that the drive goes into the STO state when switching off. The drive can only be switched on if STO was again deselected. The logic to transition into STO when switching off as well as when switching on the drive is programmed in the F-CPU. The G120 drive lineup comprises a CU240E-2 PN-F Control Unit, a PM240 Power Module and a 1LA7060-4AB10-Z induction motor. The safety-related signals are sensed using fail-safe inputs of the F-CPU and evaluated in the F-CPU. The safety functions integrated in the drive are controlled via the fail-safe PROFIsafe communication.


Content of downloads


Documentation 82526133_MC_FE_I_020_V10_en.pdf ( 4049 KB )
Code MC_FE_I_020_V10.zip ( 1391 KB )

Security note
The functions and solutions described in this article are restricted primarily to the implementation of the automation task. Please also note that in case of networking your plant area with other parts of the plant, the company network or the Internet, appropriate protective measures within the framework of industrial security must be adopted. For more information, see the entry ID 50203404.

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