In {HEAD ~ the absence} of {TAIL ~ pressurized water flow}, the bar magnet drops into magnetic field coupling proximity with the reversing reed switch SW2 
of
In { HEAD ~ the absence } of { TAIL ~ pressurized water flow } , the bar magnet drops into magnetic field coupling proximity with the reversing reed switch SW2
OTH HEAD HEAD HEAD HEAD HEAD HEAD REL TAIL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH