What is BS EN IEC 62271‑107 on Alternating current fused circuit-switchers about?
BS EN IEC 62271‑107 is the 107th part of an international multi-series standard that covers general specifications for high-voltage switchgear and control gear.
BS EN IEC 62271‑107 applies to three-pole-operated alternating current fused circuit-switchers designed with rated voltages above 1 kV up to and including 52 kV for use on three-phase alternating current systems of either 50 Hz or 60 Hz.
They can be designed either as stand-alone devices or be embedded in switchgear and control gear assembly.
BS EN IEC 62271‑107 gives specifications for the switchers that are intended to be used for circuits or applications requiring only a normal mechanical and electrical endurance capability. Such applications cover the protection of HV/LV transformers for instance but exclude distribution lines or cables, as well as motor circuits and capacitor bank circuits.
Note 1: Devices that require a dependent manual operation are not covered by BS EN IEC 62271‑107.
Who is BS EN IEC 62271‑107 on Alternating current fused circuit-switchers for?
BS EN IEC 62271‑107 on alternating current fused circuit-switchers is useful for:
- Manufacturers and suppliers of AC fused circuit-switchers
- Dealers and distributors of AC fused circuit-switchers
- Designers and developers of AC fused circuit-switchers
- Test/ service providers for AC fused circuit-switchers
Why should you use BS EN IEC 62271‑107 on Alternating current fused circuit-switchers?
Alternating current fused circuit switchers are developed to control and overcome some of the restrictions of fusing for power transformers.
BS EN IEC 62271‑107 contains the guidelines for general requirements and test specifications for alternating current fused circuit switchers that comply with the international standard. It helps you to design and manufacture circuit switchers to provide three-phase interruption (solving the unbalanced voltage considerations).
BS EN IEC 62271‑107 helps you with the standardization of alternating current fused circuit switchers by specifying the technicalities which enable you to provide protection for transient over-voltages and overloads in a very cost-efficient way in comparison with power fuses and circuit breakers.
What’s changed since the last update?
BS EN IEC 62271‑107:2019 supersedes BS EN 62271‑107:2012, which is withdrawn.
BS EN IEC 62271‑107:2019 includes the following significant technical changes with respect to the previous edition:
- Technical changes introduced by the second edition of IEC 62271-1 are applied, where relevant
- Rated TRV is removed and TRV is now treated as a test parameter, as in IEC 62271-100
- The term "thermal current" is no longer used; the rated continuous current is linked to the installed fuse-links, and values shall be provided by the manufacturer together with the list of the acceptable fuse-links; for tests purpose, the highest-rated continuous current listed is referred, where previously the wording was "rated maximum thermal current", for consistency with IEC 62271-105
- Making and breaking test duties are independent type tests (as some may be omitted if the switching device has been validated as a load-break switch)
- Differentiation has been introduced between requirements expressed for fulfilling the function expected from a fused circuit-switch, from requirements only relevant when the function is performed by a stand-alone device

