A paddlewheel meter is an inexpensive device that can be used to measure water-like
fluids. Most paddlewheel meters consist of two main pieces: the paddlewheel
sensor and the installation fitting.
The sensor body: Typically this impeller-type insertion meter consists
of the impeller(rotor), bearing assembly, sensor body, and hall
effect switch. The sensor body is available in different materials
of construction. The rotor blades have magnets imbedded in the tips,
so the rotation of the rotor is detected by the non-drag hall effect
sensor. The hall effect sensor produces a pulse-type square wave
output which can travel distances up to 2000 feet without a transmitter.
This signal with optional electronics can be use to indicate rate
of flow, total, or produce analog signals like a 4-20 madc.
This flow sensor is available for use with battery power.
The installation fitting: Made out of various materials(bronze,
pvc, stst) the fittings are usually a tee or saddle design. Tee
style fittings(up thru 2”) are tested at factory and come
with a K-factor. Remember the K-factor is the number of pulses per
gallon that a meter will generate. For saddles or insertion sensor
that are installed into large existing line a nominal k-factor is
available via a look up chart. The factor will be dependent on line
size, schedule, and material.