IEC 62271-112-2013 pdf High-voltage switchgear and controlgear – Part 112: Alternating current high-speed earthing switches for secondary arc extinction on transmission lines

3.1 .1 04 successive fault additional earth fault that occurs in the adjacent phase circuit(s) during the time interval between a single-phase earth fault and the opening of the high-speed earthing switch(es) 3.2 Assemblies of switchgear and controlgear No particular definitions. 3.3 Parts of assemblies No particular definitions. 3.4 Switching devices
6.1 05.3 Arrangement of HSES before the test The HSES under test shall be completely mounted on its own support or on a mechanically equivalent test support. Its operating device shall be operated in the manner prescribed and, in particular, if it is electrically, hydraulically or pneumatically operated, it shall be operated either at the minimum supply voltage or at the minimum functional pressure for operation, respectively. Before commencing making and breaking tests, no-load operations shall be made and details of the operating characteristics of the HSES, such as travel characteristics, closing time and opening time, shall be recorded. If applicable, tests shall be performed at the minimum functional pressure for interruption and insulation. 6.1 05.4 Behaviour of HSES during the test The HSES shall perform successfully without undue mechanical or electrical distress.
8 Guide to the selection of HSES For the selection of HSES described in Table 1 and also Tables B.1 and B.2 if necessary, the following conditions and requirements at site shall be considered: – existing fault conditions; – number of circuits; – auto-reclosing scheme (single or multi auto-reclosing scheme); – required operating sequence; – the operating sequence is linked to circuit-breaker operating sequence; – consideration on successive faults and other special conditions such as delayed current zero phenomena during HSES operations; – required operational performance (mechanical endurance); – switching requirements (fault making capability); – class M1 is mainly for applications where the high-speed earthing switch is operated in special requirement where frequent lightning strokes occur; 9 Information to be given with enquiries, tenders and orders Clause 9 of IEC 62271 -1 :2007 is applicable.