IEC 60947-5-3 ED3

Low-voltage switchgear and controlgear - Part 5-3: Control circuit devices and switching elements - Requirements for proximity devices with defined behaviour under fault conditions (PDDB)

Scope

This third edition cancels and replaces the second edition published in 2013. This edition constitutes a technical revision.
This third edition includes the following significant technical changes with respect to the previous edition:

a) Update of the scope, refined fault performance aspects and relation to standards of functional safety.
b) The ‘safe state’ is generally determined as ‘OFF-state’ (see 3.1.8).
c) Update of EMC requirements in 8.2.6 with references to IEC 60947-5-2:2019 for acceptance criteria A, B and C and requirements of Table 17 for acceptance criterion DS.
d) Interface types for binary interfaces are introduced (see 4.6.2 and Annex B).
e) Functional safety device types according to ISO 13849-1:2023 Annex O (see 4.9).
f) Interlocking device type and coding level according to ISO 14119 are adapted (see 4.10 and 4.11).
g) The operating modes target present (4.12.2) and target absent (4.12.3) are introduced.
h) The ‘switching distance’ replaces the terms ‘release’ and ‘operating’. The behaviour of the PDDB is described according to the operating mode (4.12).
i) The context and verification of the switching distances are considered according to ISO/IEC Guide 98-3:2008 (GUM) and IEC TR 63649 (see 8.2.1.3 and 9.4.2).
j) Requirements for electrical equipment class III are refined.
k) The risk time is replaced with the safety response time (3.1.11).
l) Annex A gives a new example of safety related control system.
m) The test sequences (see 9.3.1) are updated for the specific behaviour of a PDDB.

This document is to be read in conjunction with IEC 60947-1:2020 and IEC 60947-5-2:2019. The provisions of Part 1 and Part 5-2 are only applicable to this document where specifically called for. The numbering of the subclauses of this document is sometimes not continuous because it is based on the numbering of the subclauses of IEC 60947-1:2020 or IEC 60947 5 2:2019.

This part of IEC 60947 provides additional requirements to those given in IEC 60947-5-2 and IEC 60947-5-1:2024, Annex D (reed contact magnetic switches). It addresses the fault performance aspects of proximity devices with a defined behaviour under fault conditions (PDDB). It does not address any other characteristics that can be required for specific applications.
This document does not apply to protective equipment to directly detect the presence of persons, that are covered by the IEC 61496 series or IEC TS 62998 series.

NOTE 1 A PDDB device can be used to detect indirectly the presence of a person, for example by detecting the position of a platform on which the operator stands (example, garbage trucks).
This document does not specify requirements for the analogue output of PDDB, if any.
This document does not deal with any specific requirements on acoustic noise as the noise emission of proximity devices is not considered to be a relevant hazard.

A PDDB product is intended to be used as sensing subsystem of a safety related control system according to IEC 62061 or ISO 13849-1. Depending on construction principles and complexity, this document is based on product development of the IEC 61508 series to meet the product specific requirements of one or more of the following:
– IEC 61508 series;
– IEC 62061;
– ISO 13849 series.

NOTE 2 The Functional safety device type classification regarding functional safety correlates with IEC 62683-2-3.

This document includes requirements for PDDB when designed for use as part of an interlocking devices according to ISO 14119.
This document does not consider aspects of:
– software updates and self-evolving behaviour;
– explosive atmospheres.