Dynasonics UFX ULTRASONIC FLOW METER - Manual (Page 6)

6
INTRODUCTION AND OPERATING THEORY
Series UFX Phase Shift Flow Meters feature advanced Trans-Phase
measuring technology, providing accurate and reliable flow velocity
assessments in closed piping systems. The UFX utilizes a non-invasive
transducer which is hand-held or strapped to the outside of a pipe.
Within seconds, the large 0.7 inch [18mm] LCD provides stable
readings in either FPS (Feet per Second) or MPS (Meters per Second).
This product is designed to operate on metal, plastic or rubber pipes
containing liquids with greater than 100 ppm of suspended solids or
entrained gases that act as reflectors.
Phase Shift flow meters utilize two piezoelectric crystals contained
within one transducer to transmit ultrasonic sound energy into the fluid
stream and receive reflected
sound from reflectors (suspended
solids or entrained gases) within
the liquid. See Figure 1. In
accordance with the theories of
Christian Johann Doppler (circa
1842), if the liquid is moving (and
therefore carrying the reflectors
with it) and oscillating energy is
imposed on the moving reflector,
the reflected energy’s frequency
of oscillation will be altered with respect to the transmitted frequency.
The magnitude of frequency change is directly proportional to the
velocity of the reflector.
FLOW
Figure 1
SPECIFICATIONS
Description Specification
Power four AA alkaline cells provide over 30 hours of
operation
Flow Range 0.30 to 30.00 FPS [0.10 to 9.00 MPS]
Temperature electronics: -28°F to +140°F [-20°C to +60°C]
transducer: -40°F to +180°F [-40°C to +82°C]
Enclosure Rating NEMA 12X, splash resistant
Accuracy ±2% full scale
Transducer Mount Hand-held (clamp on), utilize acoustic
couplant such as DOW 111