When the valve is closed, {HEAD ~ current} flows from electrode 240 to {TAIL ~ electrode} 242 through strip 245 
When the valve is closed , { HEAD ~ current } flows from electrode 240 to { TAIL ~ electrode } 242 through strip 245
OTH OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD REL OTH OTH OTH REL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH