MT 1 - TC 17/MT 1

IEC 62271-1:2017 applies to AC switchgear and controlgear designed for indoor and/or outdoor installation and for operation at service frequencies up to and including 60 Hz and having rated voltages above 1 000 V.
This document applies to all high-voltage switchgear and controlgear except as otherwise specified in the relevant IEC standards for the particular type of switchgear and controlgear.
This second edition cancels and replaces the first edition published in 2007 and Amendment 1:2011. This edition constitutes a technical revision.
This edition includes the following significant technical changes with respect to the previous edition:
New numbering in accordance with ISO/IEC directives, Part 2 (2016) and IEEE Std. C37.100.1.
4.1.2 a) The normal service condition for indoor switchgear is limited to one range of 40 °C to -5 °C.
4.1.3 a) The normal service condition for outdoor switchgear is limited to one range of 40 °C to -25 °C.
4.2.2: The specifications from IEC 60071-2:1996 are adopted for altitude correction factors above 1 000 m.
5.2.2: Range I, the rated voltage of 40,5 kV is added Series I Table 1; Table 2 and Table 4 are updated on recommendation of the US National Committee.
6.8: New subclause added for manual operated actuators consistent with “Man Machine Interface” recommendations of IEC 60447 .
7.2.6.1:Insert the wording regarding preliminary impulses across open vacuum interrupters according to the result of IEC 17/1026/RQ.
7.3: Changed the requirement for radio interference voltage to a rated voltage level of 245 kV and above, instead of 123 kV and above. This change is based on reported positive test and service experience of utility representatives in the maintenance team of this standard.
7.5.6, Table 14:
a. Introduced the distinction of parts in “OG” (oxidizing gas) or in “NOG” (not oxidizing gas) replacing the former “air” and “SF6”;
b. Increased the allowable temperature rise for some parts in groups 1 and 2 of Table 14 according to IEC TR 60943;
c. Expanded the definition of allowable temperature rise for categories of accessible surfaces with reference to IEC Guide 117. See also Point 15 in 7.5.6.2.
7.5.6.2: Point 5 is modified to clarify the introduction of “OG” and “NOG” gas.
7.10: Some tests were removed because the relevant test standards of IEC 60068 series were modified or withdrawn.
7.11.3: The acceptance criteria for X-radiation testing are modified to recognize higher rated vacuum interrupters.
Former informative Annex H: Corrosion is deleted, the content is part of
IEC TR 62271-306.
New Annex J (informative): Added informative guidelines for the extension of validity of type tests
New Annex K (informative): Added informative guidelines about exposure to pollution
The contents of the Interpretation Sheet 1 of May 2021 have been included in this copy.