8 STO (safe torque off)
Brake output not safety-oriented
The brake is actuated via the non-safety-oriented firmware of the servo drive. If the
application requires the safe actuation of the brake, additional external measures must
be implemented.
Motor coasts down in an unbraked manner
If one of the control inputs STOA or STOB is deactivated while the power output stage is
active, the drive will coast down in an unbraked manner if the holding brake is not
connected. As a result, the machine will be damaged.
Connect the holding brake to the servo drive.
Undersized holding brake
Check whether your motors with a holding brake are suitable for braking and stopping
the motor in the event of an error by way of the holding brake.
It is possible to request the safe state while the actuation of the power semiconductors
(PWM) is active. However, an acknowledgeable error message will be issued. The status
of the voltages will be checked and assessed every 10 ms. If they are unequal over a
longer period of time, an error message will be issued. See section 8.11
Product manual BL 4000-C
Page 200 of 298