The system controller can be coupled to {HEAD ~ various sensing devices} to monitor {TAIL ~ certain variables} or physical phenomena, process the variables, and output control signals to control devices to take necessary actions when the variable levels exceed or drop below selected or predetermined values 
to monitor
The system controller can be coupled to { HEAD ~ various sensing devices } to monitor { TAIL ~ certain variables } or physical phenomena , process the variables , and output control signals to control devices to take necessary actions when the variable levels exceed or drop below selected or predetermined values
OTH OTH OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD HEAD REL REL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH