Chauvin Arnoux LOCATO 110 Mode D'emploi page 44

1st solution
This first solution consists of using a two wire lead connected to one side
of the Emitter and to its battery power supply. On the other side the two
wires are joined, making a loop. Along the lead, as the magnetic fields tend
to cancel each other, the detection will be almost zero. At the point where
the loop is joined, the detection will be greater. This is then the point where
the pipe is blocked.
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