Patent ID: 8325050

Claim:
A system for non-intrusively monitoring flow in a fluid distribution system having a fluid flow meter associated therewith, comprising: a) a sensor assembly adapted for adjustable placement proximate a meter in a fluid distribution system, said sensor assembly adapted to generate an electrical signal representative of a flow of fluid through said meter; and b) a programmable microprocessor operably attached to said sensor assembly for receiving said electrical signal, comprising: I) A/D converter; ii) means for measuring time; iii) means for indicating a magnitude of said electrical signal; IV) means to measure the amount of fluid flowing; and V) means for generating an alarm signal based on a predetermined relationship of flow and time; wherein said sensor assembly comprises a light-emitting element, a transmitting lens, a photosensitive element, a receiving lens and a plurality of lenses; wherein a mechanical package is constructed so that the surfaces holding the LED and the transmitting lens are parallel to each other and perpendicular to the transmitting optical axis and the surfaces holding the photosensitive element and the receiving lens are parallel to each other and perpendicular to the receiving optical axis.