Safety-Related Functions And Interfaces; Introduction - Universal Robots UR3/CB3 User Manual

2 Safety-related Functions and Interfaces

2.1 Introduction

UR robots are equipped with a range of built-in safety-related functions as well as
safety-related electrical interfaces to connect to other machines and additional protec-
tive devices. Each safety function and interface is monitored according to EN ISO13849-
1:2008 (see Chapter 8 for certifications) with Performance Level d (PLd).
See chapter 10 in part II for configuration of the safety-related features, inputs, and
outputs in the user interface. See chapter 5 for descriptions on how to connect safety
devices to the electrical interface.
The robot has a number of safety-related functions that can be used to limit the move-
ment of its joints and of the robot Tool Center Point (TCP). The TCP is the center point
of the output flange with the addition of the TCP offset.
The limiting safety-related functions are:
Version 3.3.3
DANGER:
Use of safety configuration parameters different from those defined
by the risk assessment conducted by the integrator can result in haz-
ards that are not reasonably eliminated or risks that are not suffi-
ciently reduced.
NOTE:
1. Use and configuration of safety-related functions and interfaces
must be done according to the risk assessment that the integra-
tor conducts for a specific robot application, see section 1.7 in
chapter 1.
2. If the robot discovers a fault or violation in the safety system,
e.g. one of the wires in the emergency stop circuit is cut, a posi-
tion sensor is broken, or a limit of a safety-related function has
been violated, a Stop Category 0 is initiated. The worst case time
from an error occurs to the robot is stopped is listed at the end
of this chapter. This time should be taken into account as part of
the risk assessment conducted by the integrator.
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