Dwyer UXF2 - Manual (Page 112)

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Symptom Cause Remedy
Measurement value
contains an error. z Inputted pipe specifications are
different from actual values.
z Scales exist on wall of old pipe.
Difference in inner diameter of 1%
produces about 3% of error.
z
Input correctly.
z When inputting, regard the scales
as lining.
z Straight pipe is inadequate
(10D upstream and 5D
downstream cannot be secured). Find a better place for mounting the
sensor (upstream the disturbance).
There must be no disturbance within
30D upstream.
Pump, valve, joint pipe, etc. are not
allowed.
z Mount the sensor at different
angles with respect to pipe cross-
section until an average is
obtained.
z Pipe is not filled with water or
contains mud or sand. Reading rises as cross-sectional area
reduces.
z
Move to vertical pipe.
BULLETIN F-70