MIR MiR250 Dynamic - Page 82

8. Safety-related functions and interfaces
MiR250 Dynamic Integrator Manual (en) 09/2023 - v.2.1 ©Copyright 2020–2023: Mobile Industrial Robots A/S. 82
In the Auxiliary emergency stop interface, pins 2 and 3 deliver 24 V, and pins 4 and 5 connect to
the Emergency stop circuit inputs of the safety PLC. 24 V must be delivered to pins 4 and 5 for the
robot to operate.
CAUTION
Emergency stop buttons are not designed for frequent use. If a button has been
used too many times, it may fail to stop the robot in an emergency situation, and
nearby personnel may be injured by electrical hazards or collision with moving parts.
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Only press Emergency stop buttons in emergencies.
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Check that all Emergency stop buttons are fully functional.
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Use the robot interface to stop the robot in non-emergency situations.
Overspeed avoidance
The Overspeed avoidance function prevents the robot from driving if the motor encoders
measure that the robot is driving faster than the predefined safety limit. This can occur if there is
a hardware error in the robot or if it drives down a steep slope. If the robot is driving faster than
the predefined safety limit, it is immediately brought into Protective stop.
Additionally, the function ensures stability when the robot pivots. If the motor encoder data
indicates that the speed difference between the two motors are above predefined limits, it might
lead to instability. If the robot is pivoting more than the predefined safety limit, it is immediately
brought into Protective stop.
Field switching and Personnel detection
The Field switching and Personnel detection safety functions are dependent on each other. The
functions make the robot enter Protective stop when the laser scanners detect a person within a
predefined area around the robot.This area is called a Protective field. There are several
predefined Protective fields that increase in size as the robot drives faster. The robot stays in
Protective stop until the active Protective field is cleared of obstacles for at least two seconds.
The Personnel detection function makes the robot stop when the laser scanners detect an
obstacle wider than approximately 70mm within the active Protective field.
If the dynamic footprint and SICKconfiguration is enabled as described in "Enabling dynamic
footprint and SICK configuration" on page46, the Personnel detection function is no longer
considered reliable and the Protective fields listed in "Field switching and Personnel detection"
above no longer applies to the robot.