MT 28 - TC 17/SC 17C/MT 28

IEC 62271-201:2026 is applicable to prefabricated solid-insulation enclosed switchgear and controlgear assemblies designed for:
– alternating current;
– rated voltages above 1 kV and up to and including 52 kV;
– service frequencies up to and including 60 Hz;
– indoor installation;
– areas limited to authorized personnel.
The assembly can include either air-insulated or fluid-filled compartments, or both.
For components installed in a solid-insulation enclosed switchgear and controlgear, this document supplements or even replaces in some cases, the requirements as stated by the individual product standards. The list of components which can be inside the solid-insulation enclosed switchgear and controlgear is not limited to the ones explicitly cited in this document. This third edition cancels and replaces the second edition published in 2014. This edition constitutes a technical revision.
This edition includes the following significant technical changes with respect to the previous edition:
a) aligned with the third edition of IEC 62271-200 published in 2021 and its Amendment 1 published in 2024, for structure, definitions, classifications, ratings and testing procedures, where appropriate;
b) clause numbering aligned with IEC 62271-1:2017, including the adoption of the subclause names of Clause 3;
c) in Clause 3 specific terms and definitions are added for "in service", "normal operating condition" and "normal use";
d) earthing circuit is more precisely described, including ratings and test requirements;
e) number of mechanical tests on interlocks is reduced for type testing;
f) forces to apply during type testing are better prescribed (refer to 7.102);
g) resistance measuring on main circuit is only needed before continuous current tests (as reference for routine tests) and not anymore needed after this continuous current test. Rationale for this deletion is that this measured resistance does not mean anything; as the temperature rise test was just finished, a new temperature rise test will not give new information;
h) IEC 62271-100:2021 has been taken into account in 7.101.2;
i) IEC 62271-107:2019 and IEC IEEE 62271-37-013:2021 are also considered in 7.101.2;
j) LSC category is more precisely described, including an explaining flowchart (Annex G);
k) examples not covered by the IAC test are transferred from Clause 6 to 9.103;
l) the term "assembly" is defined in Clause 3 and used as synonym for "solid-insulation enclosed switchgear and controlgear" in this document;
m) "metallic" is replaced by "metal" where applicable;
n) a 1 s rule was introduced for Criterion 4 during IAC tests regarding hot gases versus glowing particles as cause of ignition;
o) internal arc tests for switchgear with protrusions are more precisely described in Annex A;
p) partitions accessible in normal use are now PA, PB1 or PB2 instead of PI which has been removed (refer to 6.103.3)

IEC 62271-201:2014 specifies requirements for prefabricated solid-insulation enclosed switchgear and controlgear for alternating current of rated voltages above 1 kV and up to and including 52 kV for indoor installation and for service frequencies up to and including 60 Hz. This second edition cancels and replaces the first edition, published in 2006. This edition constitutes a technical revision. This edition includes the following significant technical changes with respect to the previous edition:
a) apart from updating with the second edition of IEC 62271-200 (issued in 2011), definitions, classifications and testing procedures have been specified more precisely;
b) access to the solid-insulation enclosed switchgear and controlgear is now restricted to authorized personnel only. This implies that "accessibility class B" (public access) has been deleted throughout the document;
c) the term "protection category" has been introduced to replace the term "protection grade" (PA, PB1 and PB2).
This publication is to be read in conjunction with IEC 62271-1:2007.

This part of IEC 62271 specifies requirements for factory-assembled insulation-enclosed switchgear and controlgear for alternating current of rated voltages above 1 kV and up to and including 52 kV for indoor installation and for service frequencies up to and including 60 Hz.