Apparatus for interrupting {HEAD ~ supply} of power from {TAIL ~ power system} to portion of consumer load in response to control signal from power system 
Apparatus for interrupting { HEAD ~ supply } of power from { TAIL ~ power system } to portion of consumer load in response to control signal from power system
OTH OTH OTH HEAD HEAD HEAD HEAD HEAD OTH OTH REL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH