This standard is applicable to three-phase alternating current switches and switch-discon-nectors designed for indoor and outdoor installation for rated voltages above 1 kV and less than 52 kV and power frequencies up to and including 60 Hz.
It is also applicable to the operating devices of these switches and to their auxiliary equipment.
Switches used in isolated neutral systems or in systems earthed by a high impedance may be required to operate under earth fault conditions. A standard is under consideration, but for the time being, a special agreement between manufacturer and user may be necessary.
Notes 1. — Except where special clarification is required the term "switch" is used to refer to all kinds of switches and switch-disconnectors within the scope of this standard.
2. — Earthing switches forming an integral part of a switch are covered by IEC Publication 129: Alternating Current Disconnectors (Isolators) and Earthing Switches. If the earthing switch has a rated short-circuit making current the making tests shall be made according to the requirements in this standard.
It is assumed that opening and closing operations are performed according to the manufac-turer's instructions. A making operation may immediately follow a breaking operation but it is strongly recommended that a breaking operation shall not immediately follow a making operation since the current to be broken may then exceed the rated breaking current of the switch.
SIS SS-IEC 265-1:1990 history
1990SIS SS-IEC 265-1:1990 High-voltage switchgear and controlgear — High-voltage switches for rated voltages above 1 kV and less than 52 kV