Definition - What does IEC 61511 mean?
IEC 61511 is a technical standard that outlines the practices in the design and engineering of systems that ensure the safety of an industrial process through instrumentation. These systems are called Safety Instrumented Systems (SISs).
The main intent of the standard is to determine the steps of taking a process to a safe state when predetermined conditions are violated, such as set points for pressure, temperature, level, etc. Its objective is to define requirements for Emergency Shutdown Systems.
Safeopedia explains IEC 61511
Endorsed as a national consensus standard by OSHA, IEC 61511 is applicable to electrical, electronic, and programmable electronic equipment in the industry sector, but it does not cover nuclear power facilities or nuclear reactors.
This standard is used to perform non-safety functions and, increasingly, to perform safety functions. It defines the functional safety requirements established by IEC 61508, as it focuses on one type of instrumented safety system used within the process sector.
IEC 61511 covers the design and management requirements for Safety Instrumented Systems and their safety life cycle from initial concept and design through implementation, operation, and maintenance, to decommissioning. There are sections that cover modifications added after startup, along with information on maintenance and decommissioning activities.