Metex 3200U Ultrasonic Flow & Level Monitor - Manual (Page 21)

TYPICAL TRANSDUCER POSITIONING
FOR FLUMES AND WEIRS
Always refer to the flume or weir manufacturer’s instructions for correct measurement point upstream
from the flume or weir. Location of the sensor is critical for accurate flow measurement.
If manufacturer’s instructions are not available, the following guidelines are generally accepted.
1.PARSHALL FLUME:
Position the sensor at 2/3 Approach
as illustrated above. Sensor height
must be 12" (30.5 cm) or more
above the highest water level.
2. PALMER BOWLUS FLUMES:
Position the sensor at 1/2 the flume
Diameter upstream from the throat
of the flume. Sensor height must be
12" / 30.5 cm (depending on sensor
model) or more above the highest
water level.
3. V-NOTCH WEIRS
Position the sensor at 3 x maximum Head upstream from
the weir plate. Sensor height must be 12" / 30.5 cm
(depending on sensor model) or more above the highest
water level.
STILLING WELLS
Stilling wells are recommended to reduce the effects of turbulence as water flows through the flume or
weir. The Ultrason sensor is centered over the stilling well. Sensor height must be 12" (30.5 cm) or more
above the highest water level. The well must be kept clean of sediments and deposits on the side walls.
AquaMetrix
Ultrason
Page 21
D
FLOW
SENSOR
POSITION
3x MAX. HEAD
WEIR
PLATE