Dynasonics DXN Portable Ultrasonic Measurement System - Manual (Page 18)

Water-Tap
Set
×
Water-Tap
Water-Black
Acetone
Ammonia
Benzine
Brine
Ethanol
Gasoline
Glycerin
Isopropanol
Kerosen
Methanol
Milk 4%
Oil Diesel
Oil Hydraulic (Petro)
Oil Lubricating
Parameter
Choices
Move
Selection
Buttons
Make
Selection
Scroll
Bar
Cancel
Figure 21: Combo Box with Large Scroll Bars
The and arrow buttons moves the blue highlights area up or down depending on the original position of the
highlight. Once the correct choice has been highlighted in blue use the set
Set
button to lock in the selection. If no change is
desired use the cancel
×
button to exit the combo box without making any changes.
If the drop-down list of parameters is too large to be contained in one combo box length a large scroll bar will be visible
allowing the list to be scrolled up or down.
A small scroll bar is also used when parameter entries are too numerous for a single screen page. The scroll bars may appear
either horizontally or vertically.
Figure 22: Small Scroll Bar
TRANSDUCER INSTALLATION
General Guidelines
At its simplest setting up the DXN portable ultrasonic measurement system consists of two steps. The first step is configuring
the electronics. The second step, mounting the transducers, requires information obtained when the electronics are
configured.
Transmission Mode
The first decision to be made is what mode of ultrasonic transmission should be used. Generally, the transit time mode is used
with fluids that have little to no particulates or entrained air. Doppler mode is used on fluids that contain significant levels of
particulates and aerated fluids. If the fluid type is unknown it is usually better to start with transit time as transit time mode is
more forgiving of having some particulate or air than Doppler is of not having enough particulate or entrained air.
If the fluid type is an unknown it is also possible to mount both transit time and Doppler transducers on the same pipe and let
the DXN decide which set of transducers to use. The DXN can operate as a dedicated transit time meter, a dedicated Doppler
meter or to automatically switch between transit time and Doppler modes using the Hybrid mode.
Transducer Mounting Location
At this point it is also necessary to consider the transducer mounting location. A very loose rule of thumb is to mount the
transducers on a section of pipe that has at least 10 pipe diameters upstream of the transducers and 5 pipe diameters
downstream. See Table 1 for additional pipe length considerations.
For example, if a 3" pipe is being measured the minimum upstream pipe in front of the transducers should be 30" and the
minimum downstream pipe behind the transducers should be at least 15".
DXN Portable Ultrasonic Measurement System
Page 18 February 2013