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SINAMICS G120D Safety Integrated

The series of SINAMICS G120D distributed inverters is the solution for sophisticated drive applications. These are especially found in the area of conveyor technology.

G120D has an extensive safety package that helps to protect personnel as well as machines. This safety package is extremely efficient and cost effective as the safety functions are completely integrated in the drive system. Not only this, your machine can be safely and practically operated under all of the specified operating conditions. For instance, in the setting-up and test modes with the protective door open. The safety functions comply with the requirements laid down in EN 61508 for use up to and including SIL 2 (Safety Integrity Level), Category 3 and PL d (Performance Level) according to EN ISO 13849-1. As a consequence, the essential requirements relating to functional safety can be simply and cost-effectively implemented.

The functional scope includes, e.g.:

  • Functions for safe stopping

  • Functions for safely monitoring motion

Product features

  • Functions to protect persons and machines

  • Short response times as the functions are integrated in the drive system

  • Can be used in all operating modes

  • Replace external electromechanical devices


The safety functions are available in all operating modes and can communicate with the process via safety-related input/output signals.

Communication via fieldbus (PROFINET or PROFIBUS) with the safety-related PROFIsafe profile is already possible in the standard version.

The safety functions are commissioned using STARTER or Startdrive.
The partially automated acceptance test for all safety-related functions can be performed with support from STARTER.

SINAMICS G120D has the following safety functions integrated in the drive:



STO - Safe Torque Off

The torque is safely shut down and prevents an inadvertent restart.
Electronic shutdown, therefore no wearing parts. The drive remains connected to the line supply and can still be fully diagnosed.

SS1 - Safe Stop 1

When a monitoring function or a sensor responds (e.g. light barrier) this function safely brings drives to a standstill (zero speed).
SS1 is also suitable for machines with high moments of inertia that must be safely and quickly braked.

SLS - Safety Limited Speed

Monitors configurable speed limit values, for instance, when setting-up without an acknowledgment button.
SLS is suitable for machines where hazards can occur if a speed is exceeded, for example.

SSM - Safe Speed Monitor

Supplies a safety output signal if the drive speed lies below a configurable limit value.
For instance, using SSM, access to the machine can be enabled using the safety-related feedback signal.

SDI – Safe Direction

Safely monitors whether the permissible motion direction is exited. If this is the case, a parameterizable stop function is activated, e.g. STO.
For instance, SDI is suitable for machines where material must be loaded or removed cyclically.

Customer benefits

  • High degree of safety:
    Safety functions are seamlessly implemented in SIL 2 (EN 61508) and PL d, Category 3 (EN ISO 13849-1)

  • High degree of flexibility:
    Practical safety and operator concepts can be realized

  • High degree of cost effectiveness:
    Hardware and installation costs are reduced

  • Higher availability:
    Electromechanical switching elements that are prone to faults are eliminated