A control unit controls either the inflow liquid pump only or both the inflow liquid pump and {TAIL ~ the outflow device} depending on an inflow irrigation liquid pressure from {HEAD ~ a pressure sensor}  
A control unit controls either the inflow liquid pump only or both the inflow liquid pump and { TAIL ~ the outflow device } depending on an inflow irrigation liquid pressure from { HEAD ~ a pressure sensor }
OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH TAIL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD HEAD OTH