
Safe Torque Off
6-23
890CS Common Bus Supply - Frames B & D; 890CD Common Bus Drive and 890SD Standalone Drive - Frames E & F
system occurs during the active braking phase, the load may coast to a stop or might even actively
accelerate until expiration of the defined time delay. It is not the remit of this document to specify these
measures. This is for the user to assess.
•
When the 890 detects either an internal STO fault or an external single-channel user fault, the user must
immediately fully resolve the fault. The user must ensure dual-channel operation has been fully restored
before attempting to use the 890 STO safety feature.
DANGER
FAILURE TO DO SO COULD RESULT IN STO NOT BEING ACHIEVABLE, AND THUS THE MOTOR
MAY ROTATE UNEXPECTEDLY AND COULD RESULT IN INJURY, DEATH OR DAMAGE.
FURTHER OPERATION OF THE 890 WITHOUT RESOLVING THIS FAILURE IS ENTIRELY AT THE
USER’S OWN RISK. SEE SAFETY CATEGORY DEFINITIONS AND LIMITATIONS, REFER TO EN
ISO 13849-1:2008.
•
It is the user’s responsibility to ensure that their overall control implementation recovers safely from
supply loss or dips.
•
In all instances it is the user’s responsibility formally to perform suitable risk assessments, and invoke and
fully validate the necessary risk reduction measures after having thoroughly understood the application,
the drive product and its features.