Integrated Safety Functions with Drives

SINAMICS Safety Integrated

Fail-safe drives are characterized by their "integrated safety functions", which they provide to the user as possible responses to safety-relevant events. The most important integrated safety functions available for Siemens drives are described in the following. The functional safety of all of the functions satisfies the requirements defined in Part 5-2 of the international standard IEC 61800 for variable-speed drive systems.

integrated safety functions

Motor starter

SIMATIC

STO

SS1

SBC

SLS

SDI

SSM

SOS

SS2

ET 200S

Yes

-

-

-

-

-

-

-

ET 200pro

Yes

-

-

-

-

-

-

-

SIMOCODE pro

Yes

-

-

-

-

-

-

-

Converter

SINAMICS

STO

SS1

SBC

SLS

SDI1)

SSM

SOS

SS2

G120C

Yes

-

-

-

-

-

-

-

G120

Yes

Yes

Yes

Yes

Yes

Yes

-

-

G120D

Yes

Yes

-

Yes

Yes

Yes

-

-

G130/G150

Yes

Yes

-

-

-

-

-

-

S110

Yes

Yes

Yes

Yes 3)

Yes3)

Yes3)

Yes3)

Yes3)

S120

Yes

Yes

Yes2)

Yes3)

Yes3)

Yes3)

Yes3)

Yes3)

S150

Yes

Yes

-

Yes3)

-

Yes3)

Yes3)

Yes3)

1) Firmware version 4.4. (or higher) 2) Applies only to Blocksize and Booksize devices 3) in In connection with sin/cos encoders

Drive-integrated safety functions without mains disconnection

Functions for safe shutdown of a drive without having to disconnect the power connection with the mains.

This includes the following functions:

  • Safe torque off (STO)
    This function ensures that no torque is transmitted by the motor shaft any longer-

  • Safe stop 1 (SS1)
    This function actively decelerates a drive before the function STO is activated. This function allows for the fast shutdown of drives with high kinetic energy in case of danger.

  • Safe stop 2 (SS2)
    Like the function SS1, SS2 actively decelerates a drive. However, the function SOS is activated instead of STO during standstill. As with SS1, this function allows for the fast shutdown of drives with high kinetic energy in case of danger.

  • Safe operating stop (SOS)
    The function SOS can be used as an alternative to STO. In contrast to STO, the motor is not switched torque-free. Instead, the drive remains in position control, holds its position and is monitored for standstill.

  • Safe brake control (SBC)
    With this function, a holding brake is safely controlled after activation of STO, as a result of which the drive can no longer move, e.g. due to gravity.


Drive-integrated safety functions for safe speed monitoring

Functions for safe speed monitoring of a drive:

  • Safely limited speed (SLS)
    This function monitors the drive for exceedance of one or more specified maximum speeds.

  • Safe speed monitor (SSM)
    This function signals shortfall of a specified speed. No drive-autonomous response is effected.

  • Safe Direction (SDI)
    This function monitors adherence to the selected direction of motion/rotation of the drive.


Drive-integrated safety functions for machine tools

The following safety functions can be realized for every single axis and spindle, especially for safety solutions in machine tools in connection with the CNC control SINUMERIK:

  • Safe stop 1 (SS1) and safe stop 2 (SS2)

  • Safe operating stop (SOS)

  • Safe torque off (STO)

  • Safely limited speed (SLS)

  • Safely limited position (SLP)

  • Safe cam (SCA)

  • Safe programmable logics (SPL)

  • Safe brake management (SBM)

  • Integrated acceptance test