[logik-lsw-start-endekriterium-170903-kn, 1, en_US]
Figure 2-139
Logic of the start and end criterion
ΣΙ-Procedure
Being a basic function, the ΣΙ-procedure is unaffected by the configuration and does not require any procedur-
especific settings. All tripping currents occurring 1½ periods after a protective trip, are summed up for each
phase. These tripping currents are r.m.s. values of the fundamental harmonic.
The interrupted current in each pole is determined for each trip signal. The interrupted fault current is indi-
cated in the fault messages and is added up with previously stored fault current values in the statistic-coun-
ters. Measured values are indicated in primary terms.
Functions
2.25 Auxiliary Functions
322 SIPROTEC 4, 7SJ62/64, Manual
C53000-G1140-C207-8, Edition 08.2016