Function description
System Description Service Robotics Modules
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4.6
Safe retention with holding brakes
The robot arm is a vertical axis, or more specifically a gravity-loaded axis. Generally, ver-
tical axes are held at standstill solely by the holding brake built into the drive motor. Mech-
anical wear on the brake, for example, can cause the axis to drop or fall unintentionally due
to gravity.
With this safety function, the holding brakes on the robot arm are checked at regular inter-
vals by a brake test. The safety control system requests a cyclical brake test from the robot
controller and evaluates the feedback in terms of safety. If the safety control system re-
ceives no feedback regarding a successful brake test within a safely monitored time, the
safety control system triggers the stop function SS1. In this case, the robot operator re-
ceives a signal that the plant/machine has been stopped and the brakes must be repaired.
Further information is available under
Robot movement with time-limited motion
.
