Propane tank level monitoring device and system

摘要

An in-line gas flow rate sensor includes a movable flow orifice and a fixed flow restrictor adjacent the flow orifice for changing the gas flow through the flow orifice. The flow orifice and the flow restrictor are formed so that each uniform increment of flow orifice movement provides a constant percent of flow change through the flow orifice. A magnet fixed to the movable flow orifice provides changing magnetic flux corresponding to each uniform increment of flow restrictor movement. A magnetic flux sensor responds to the changing magnetic flux and provides an output corresponding to a constant percent of flow rate changes.