User manual

14 Publication 1756-RM093F-EN-P - January 2010
Chapter 1 Safety Integrity Level (SIL) Concept
The TÜV Rheinland has approved GuardLogix controller systems for
use in safety-related applications up to SIL 3, in which the
de-energized state is considered to be the safe state. All of the
examples related to I/O included in this manual are based on
achieving de-energization as the safe state for typical Machine Safety
and Emergency Shutdown (ESD) Systems.
When applying Functional Safety, restrict access to qualified,
authorized personnel who are trained and experienced. The
safety-lock function, with passwords, is provided in RSLogix 5000
software.
For information on using the safety-lock feature, refer to the
GuardLogix Controllers User Manual, publication 1756-UM020
or the
1768 Compact GuardLogix Controllers User Manual publication
1768-UM002
.
Functional Verification
Tests
IEC 61508 requires the user to perform various functional verification
tests of the equipment used in the system. Functional verification tests
are performed at user-defined times. For example, functional
verification test intervals can be once a year, once every 15 years, or
whatever timeframe is appropriate.
GuardLogix controllers have a functional verification test interval of
up to 20 years. Other components of the system, such as Safety I/O
modules, sensors, and actuators may have shorter functional
verification test intervals. The controller should be included in the
functional verification testing of the other components in the safety
system.
For more information on the requirements of a functional verification
test, see Project Verification Test
on pages 57 and 58.
IMPORTANT
The system user is responsible for:
• the set-up, SIL rating, and validation of any sensors or actuators
connected to the GuardLogix system.
• project management and functional testing.
• access control to the safety system, including password handling.
• programming the application software and the device
configurations in accordance with the information in this safety
reference manual and the GuardLogix Controllers User Manual,
publication 1756-UM020
, or the 1768 Compact GuardLogix
Controllers User Manual publication 1768-UM002.
IMPORTANT
Your specific applications determine the timeframe for the
functional verification test interval. However this is mainly
related to Safety I/O modules and field instrumentation.