EN IEC 60947-6-1:2026/prAA

Low-voltage switchgear and controlgear - Part 6-1: Multiple function equipment - Transfer switching equipment

Scope

This standard applies to transfer switching equipment (TSE), to be used in power systems for ensuring the continuity of the supply and allowing the energy management of the installation, by transferring a load between power supply sources, the rated voltage of which does not exceed 1 000 V AC or 1 500 V DC. Specific requirements for bypass/isolation transfer switch equipment are given in Annex C, ATSE having closed transition capability are given in Annex D, stand-alone ATS controllers are given in Annex E, and TSE for electric driven fire pump controllers are given in Annex F.
It covers:
- manually operated transfer switching equipment (MTSE);
- remotely operated transfer switching equipment (RTSE);
- automatic transfer switching equipment (ATSE), including the controller;
- stand-alone ATS controllers;
- bypass/isolation transfer switch equipment (BTSE);
- ATSE having closed transition capability;
- fire pump TSE.
It does not cover:
- TSE configurations that are not fully manufacturer type tested or marked according to this document as a complete transfer switch;
- auxiliary contacts (for guidance, see IEC 60947-5-1);
- transfer switches used in explosive atmospheres (for guidance, see IEC 60079 (all parts));
- embedded software design (for guidance, see IEC TR 63201);
- cybersecurity aspects (for guidance, see IEC 63208);
- TSE rated for direct-on-line starting asynchronous motor of design NE and HE, according to IEC 60034-12. (for guidance, see AC-3e utilisation category according to IEC 60947 4 1);
- other types of TSE under consideration including overlapping neutral TSE, multi-source TSE (i.e. TSE with more than two sources of supply), TSE with load-shedding functions, bus-tie TSE, and hybrid TSE;
- static transfer switches covered by IEC 62310 series.
This fourth edition cancels and replaces the third edition published in 2021. This edition constitutes a technical revision.
This edition includes the following significant technical changes with respect to the previous edition:
- clarification of scope;
- clarification of terms and definitions;
- Annex C for Bypass/Isolation Transfer Switch Equipment;
- Annex D for ATSE having closed transition capability;
- Annex E for Stand-alone ATS controller;
- Annex F for TSE used with electric driven fire pump control equipment.

Related legislation

Legislation related to this standard