Repeated energizing of AC circuit switchgear

摘要

In the AC circuit the contact voltage at the switching contacts (2) of the switchgear (1) is detected. The switching in nearest proximity to the respective voltage or load current zero passage is attained by the first ON or OFF of the switchgear the actual delay of the latter is measured. At the following switching steps each time point for giving the control ON or OFF instruction to the switchgear is computed by the microcontroller (8), taking into account the previously measured ON and OFF delay for the above nearest proximity.