AS IEC 62271.105 pdf download.High-voltage switchgear and control gear Part 105: Alternating current switch- fuse combinations for rated voltages above 1 kV up to and including 52 kV
1 General
1 .1 Scope
Subclause 1 .1 of IEC 62271 -1 :2007 is not applicable, and is replaced as follows:. This part of IEC 62271 applies to three-pole units for public and industrial distribution systems which are functional assemblies of switches including switch-disconnectors and current- limiting fuses designed so as to be capable of – breaking, at the rated recovery voltage, any current up to and including the rated short- circuit breaking current; – making, at the rated voltage, circuits to which the rated short-circuit breaking current applies. It does not apply to fuse-circuit-breakers, fuse-contactors, combinations for motor-circuits or to combinations incorporating single capacitor bank switches. In this standard, the word “combination” is used for a combination in which the components constitute a functional assembly. Each association of a given type of switch and a given type of fuse defines one type of combination. In practice, different types of fuses may be combined with one type of switch, which give several combinations with different characteristics, in particular concerning the rated currents. Moreover, for maintenance purposes, the user should know the types of fuses that can be combined to a given switch without impairing compliance to the standard, and the corresponding characteristics of the so-made combination.A switch-fuse combination is then defined by its type designation and a list of selected fuses is defined by the manufacturer, the so-called “reference list of fuses”. Compliance with this standard of a given combination means that every combination using one of the selected fuses is proven to be in compliance with this standard. The fuses are incorporated in order to extend the short-circuit breaking rating of the combination beyond that of the switch alone. They are fitted with strikers in order both to open automatically all three poles of the switch on the operation of a fuse and to achieve a correct operation at values of fault current above the minimum melting current but below the minimum breaking current of the fuses. In addition to the fuse strikers, the combination may be fitted with either an over-current release or a shunt release. NOTE In this standard the term “fuse” is used to designate either the fuse or the fuse-link where the general meaning of the text does not result in ambiguity. This standard applies to combinations 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. Fuses are covered by IEC 60282-1 . Devices that require dependent manual operation are not covered by this standard.Switches, including their specific mechanism, shall be in accordance with IEC 62271 -1 03 except for the short-time current and short-circuit making requirements where the current- limiting effects of the fuses are taken into account. Earthing switches forming an integral part of a combination are covered by IEC 62271 -1 02.
3 Terms and definitions
Clause 3 of IEC 62271 -1 :2007 is applicable with the the following additions. 3.1 General terms Subclause 3.1 of IEC 62271 -1 :2007 is applicable. 3.2 Assemblies of switchgear and controlgear Subclause 3.2 of IEC 62271 -1 :2007 is applicable. 3.3 Parts of assemblies Subclause 3.3 of IEC 62271 -1 :2007 is applicable. 3.4 Switching devices Subclause 3.4 of IEC 62271 -1 :2007 is applicable, with the following additions 3.4.1 01 switch-fuse combination combination of a three-pole switch with three fuses provided with strikers, the operation of any striker causing all three poles of the switch to open automatically Note 1 to entry: The switch-fuse combination includes fuse-switch combination. 3.4.1 02 switch-fuse combination base combination base switch-fuse combination without fuse-links mounted 3.4.1 03 switch-fuse switch in which one or more poles have a fuse in series in a composite unit [SOURCE: IEC 60050-441 :2007, 441 -1 4-1 4] 3.4.1 04 fuse-switch switch in which a fuse-link or a fuse-carrier with fuse-link forms the moving contact [SOURCE: IEC 60050-441 :2007, 441 -1 4-1 7] 3.4.1 05 switch-disconnector switch which, in the open position, satisfies the isolating requirements specified for a disconnector [SOURCE: IEC 60050-441 :2007, 441 -1 4-1 2] 3.4.1 06 release operated combination combination in which automatic opening of the switch can also be initiated by either an over- current release or a shunt release
AS IEC 62271.105 pdf download
