Selective network monitoring system for switchgear

摘要

The network monitoring system detects the electrical post- arc currents and following the zero current and compares them with a given limiting current value, for operation of a power cut-out switch for the switch appts when the limit current value is exceeded. Pref. the post-arc current is measured after the first zero-crossing of the opened switch pole, with the limiting current value lying within the range of 5 to 15 A. Pref. the operation of cut-out switches (21,22) for parts of the supply system are monitored for operation of a main cut-out switch (2).