Complex sentence: Autoreclosers sense and interrupt brief fault currents and then automatically attempt to restore service a few times (typically 3 or 4); in the meanwhile, (while unenergized) the sectionalizer automatically opens in an attempt to isolate the fault from the energy source.
Split into simpler sentences: Autoreclosers sense and interrupt brief fault currents and then automatically attempt to restore service a few times (typically 3 or 4). Meanwhile, the unenergized sectionalizer automatically opens in an attempt to isolate the fault from the energy source.