Safe torque off (STO)

This function is also called an “uncontrolled stop” and leads to an immediate removal of power to the machine actuators.  

Activation of the mains isolating device automatically triggers this category of stop. During operation, this function causes the motor to run down in an uncontrolled manner, which is not desirable in practice. That is why this function is mostly combined with the safety function (SS1) or used as a safe restart interlock.

Further information on safe motion monitoring can be found on our application page:

Safe motion monitoring