Page 52
Sonic-Pro
Industries, Ltd.
Industries, Ltd.
ProSeries
by Blue-White Ind.
TM
The field in the top center of the display status line displays the “Goodness of
Measurement” which indicates the reliability of ultrasonic flow measurement under the
present working conditions. This is computed by the algorithms that determine fluid
velocity. The average of all samples computed during each display update interval is
taken and then displayed as a reliability index of 0 to 4 bars. Zero bars indicate
an unreliable measurement and four bars indicate high reliability.
The same goodness of measurement indication appears on the four amber LEDs on the
controller motherboard, which can be viewed if the wiring access door is removed.
If flow measurement is restarted (by passing through the Startup State), then prior
goodness of measurement information is discarded and the display will show zero until
new information is computed.
The field on the top right displays either a speed of sound measurement value (if in
Transit Time mode) or a zero (if in Doppler mode).
When operated in the transit time mode, the flowmeter periodically calculates the speed
that sound is traveling through the fluid and displays the resulting value in meters per
second. This value is useful for determining the reliability of the measurement and also
for configuring the meter for unknown
Custom Fluids
.
in the index at
the end of this manual.
Should the displayed value not match, one or more of the following conditions may exist:
!
The transducers are not positioned correctly
!
The pipe material
!
!
The fluid type does not match the
Fluid Type
specified in the
Transducer Setup
configuration menu
!
The fluid’s temperature is different than the temperature of the index values
When the meter is set for Doppler measurement, a zero will be displayed.
See section 7.2.4 below for information on
The following outlines how to use the flowmeter to determine the speed of sound in a
fluid. For the flowmeter to function, the precise speed of sound does not need to be known
in advance. However, to place the transducers in the optimal location, knowing the speed
of sound in the fluid is important. The following outlines a procedure that you can follow
in determining the fluid speed of sound.
!
This test can be performed with or without flow. It is recommended that the test be
performed with zero flow.
!
The pipe outer diameter and wall thickness should be known precisely. It is
recommended to use a small section of pipe so that the exact dimensions can be
measured.
!
The speed of sound calculation is also affected by transducer placement. Any error in
the spacing of the transducers will translate to an error in the calculated speed of
sound.
A list of the
Fluid Types
that
are available for selection in the meter and their sound speed is shown
The displayed value should closely match the fluid’s sound speed.
type does not match the
Pipe Material Type
specified in the
Transducer Setup
configuration menu
The pipe wall thickness is other than specified in the
Transducer Setup
configuration menu
configuring the meter for unknown Custom
Fluids.
[
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7.2.2
Goodness of
Measurement
7.2.3
Sound Speed
Display
7.2.4
Measuring the
Fluid Sound
Speed
