IEC 61800-5-3:2021

IEC 61800-5-3:2021, which is a product standard, specifies requirements and makes recommendations for the design and development, integration and validation of safety-related _encoder_ (_Encoder(SR)_) in terms of their _functional safety_ considerations, electrical safety and environmental conditions. It applies to _Encoder(SR)_, being sensors as part of a _PDS(SR)_. This document can also be referred to and used for _Encoder(SR)_ in any other safety-related application, for example safety-related position monitoring.
This document is applicable where _functional safety_ of an _encoder_ is claimed and the _Encoder(SR) _is operating mainly in the high demand or continuous mode. The requirements of IEC 61800-5-2:2016 for _PDS(SR)_ apply to _Encoder(SR)_ as applicable.
This document includes additional or different requirements for _Encoder(SR)_. It sets out safety-related considerations of _Encoder(SR) _in terms of the framework of IEC 61508 (all parts), and introduces requirements for _Encoder(SR) _as subsystems of a safety-related system. It is intended to facilitate the realisation of the electrical/electronic/programmable electronic (E/E/PE) and mechanical parts of an _Encoder(SR) _in relation to the safety performance of _safety sub-function_(s) of an _Encoder(SR)_.