1. Ultrasonic Flow Measurement Principles & Introduction
Series PUX2
Series UXF3
The materials included in this compilation are for the use of
Dwyer Instruments, Inc. potential customers and current
employees as a resource only. They may not be reproduced,
published, or transmitted electronically for commercial
purposes. Furthermore, the Company’s name, likeness,
product names, and logos, included within these compilations
Series UXF2 may not be used without specific, written prior permission
from Dwyer Instruments, Inc.
©Copyright 2011 Dwyer Instruments, Inc.

2. Transit Time Measuring Principle
• Clamp-on sensors Upstream Sensor
Oscillator Wedge
• Transit-time difference system Pipe
• Principle equation:
Q
D θf
１
Q=─π D2 / 4 * ── * D/sin2θf * 1/(T0-τ)2 ΔT
K
Downstream
τ/2 τ/2 Sensor
T1
T2
• Q : Flow rate • T1, T2 : Transit time ΔT=T2－T1
• D : Inner pipe diameter • T0 : Transit time between sensors
• K : Conversion factor when flow is at rest (Note)
of average velocity (≒(T1+ T2 )/2) Ultrasonic waves are
• θf: Incident angle into liquid • τ : Transit time in pipe walls and carried with the motion of
sensors fluid.

3. Advanced ABM (Anti-bubble Measurement)
 Utilized in Model PUX2, UXF3
 Digital sampling of received signals increases flow reading reliability
 Synchronized summation of received signals :
- Normal propagation
Received signal :
flow v
bubble
t
Digital data of
Summed received signals :
128 or 256 v
- Interrupted propagation times for
one output t
Received signal :
flow v
bubble t
Nothing!
In case of analog system no –
signal, intermittent loss of
receive echo

4. Result of Bubble Immersion Test
12
12
Permissible Air Volume
10
8
7.0
[vol. %]
Models PUX2, UXF3
6
4.0
4
Model UXF2 1.5
2 1.2
0.4 0.03 1.0
0.02
1 0.02
1.0 2.0 3.0 4.0 5.0
Velocity [m/s]
(Note) The flowmeters indicate volumetric flow rate containing air volume.

5. Sound Velocity Measurement System
Upstream Sensor
 Patented sound velocity compensation – all
Pipe
models
Effect of temp./
pressure change
 Changing process conditions (temp/pressure) D θf Q
Sound
change fluid sound velocity (changes results) Velocity Cf
Downstream
 Changing temp/pressure can be ignored if sound τ/2 τ/2 Sensor
T1
velocity is constantly measured and compensated T2
 Sound velocity compensation system tracks and
adjusts “θ” and “τ”
Successive calculation with sensors‘ spacing having no change from the set value

6. Model Specifications & Applications
• 0.5” – 235” diameter, up to 12% air/solids
• Digital fine filter & correlation
• 12 hour battery, data logger, memory card &
PUX2 printer (options)
• 0.5” – 235” diameter, up to 12% air/solids
• Digital fine filter & correlation
UXF3
• Full featured, flexible I/O, IP65 enclosure
• 1” – 24” diameter, up to 1.5% air/solids
• Advanced transit time technology
• Full featured, flexible I/O, highly competitive
UXF2

7. PUX2 Specifications
Dwyer Instruments PUX2
Measurement Method Transit Time
Pipe sizes 0.50 to 236 inch diameter
Number of Paths 1 path
Fluid temperature -40 to +80℃/100℃/200℃
Ambient temperature -10 to +55℃ (Printer 45℃)
Air bubble resistance 12 Vol% (at 1m/s)
Accuracy +/-1.0% of rate
Velocity range 0 to +/- 32m/s (105 fps)
Output Analog Output: 1point 4-20mA; Heat Transfer Rate Function
Input Analog Input: 1 point 4-20 mA
Serial communication USB Port (Mini type B, 500kbps)
Key 11 keys (ON, OFF, LEFT, RIGHT, UP, DOWN, ESC,
ENT, MENU, BACKLIGHT, PRINT)
Display 240 X 320 Color LCD
Language 6 languages (ENG, ESP, GER, FRA, JAP, CHI)
Power Supply Built-in battery or power adapter
Built-in battery: L-Ion battery, approximately 12 hours
Power adaptor: AC Power Adapter/Charger 90 to 264V
Dimensions H210 x W120 x D65mm (without printer)
H320 x W127 x D70mm (with printer)
Mass: 1.0 kg (without printer)
1.2 kg (with printer)
Type of Enclosure IP64 (Plastic)

8. UXF3 Specifications
Dwyer Instruments UXF3
Measurement Method Transit Time
Pipe sizes 0.50 to 235 inch diameter
Number of Paths 1 path
Fluid temperature -40 to +80℃/100℃/200℃
Ambient temperature -10 to +55℃
Air bubble resistance 12 Vol% (at 1m/s)
Accuracy +/-1.0% of rate
Velocity range 0 to +/- 32m/s (105 fps)
Output One 4 to 20mA DC current output…Max. load
resistance 1kΩ
Input: 1 digital input, 1 pt. - No Voltage Digital status output: 2 points available - 30V DC,
transistor switch; set zero/reset 0.1A…Total pulse, Flow switch, Over flow, Range
totalizer change-over, Flow direction, Range over
Mechanical relay: 1 pt available; 240VAC/30VDC-1 amp
Serial communication RS232C/Modbus RS485 option; Baud rate: 9600 to
39400 bps; Distance: 15m(RS232)/1000m(RS485) max.
Key 4 key keyboard; menu driven programming
Display LCD with back light, 16 x 2 lines
Language 5 languages (ENG, ESP, GER, FRA, JAP)
Power Supply 100 to 240V AC 50/60Hz, or 20 to 30V DC
Dimensions H170 x W142 x D70mm
Type of Enclosure IP66 (1.5 kg)

9. UXF2 Specifications
Dwyer Instruments UXF2
Measurement Method Transit Time
Pipe sizes 1 to 24 inch (plastic pipe); 2 to 24 inch (metal)
Number of Paths 1 path
Fluid temperature -40 to +80℃/100℃
Ambient temperature -20 to +50℃
Air bubble resistance 1.2 Vol% (at 1m/s)
Accuracy 2% of rate (>2m/s), 0.04m/s (<2m/s)
Velocity range 0 to +/- 10 m/s (33 fps)
Output 4 to 20mAdc, 1 point
Digital output: Relay & transistor, each 1 point (scaled
totalizer pulse, alarm, etc.)
Scaled pulse: 1pulse/day to 100pps for transistor output
1pulse/day to 1pps for relay output
Serial communication RS-232C equivalent / RS-485
Number of connectable units: one (RS-485)/
up to 31 (RS-485)
Cable length: up to 15m (RS-232C)/up to 1km (RS-485)
Key 4 key front panel keyboard; menu driven programming
Display LCD 2 lines 32 characters - backlight
Language 5 languages (incl. Spanish)
Power Supply 20 to 30Vdc, 100 to 120Vac or 200 to 240Vac, 50/60Hz
Dimensions Dimensions of converter: H140 x W137 x D68mm
Mass of converter: approx, 0.8 kg
Type of Enclosure IP65 (Plastic)

10. Sensor Mount & UXF2 Sensor Selection
• “V” mount configuration • “Z” mount configuration
• Typical setup; recommended for most cases • Single reflection reduces signal attenuation
having sufficient return signal
• Effective at upper end of sensor diameter range or
• Sensors mounted axially on the same side specific circumstances to increase return signal
Type Model No. Pipe size Fluid temp.
SX3-A 1 4 in (V-mount) -20 +100℃
SX3-B 2 9 in (V) -20 +100℃
UXF2
SX3-C 2 12 in (V) -20 +80℃
SX3-D 12 24 in (Z) -20 +80℃

11. Sensor Selection PUX2, UXF3
Type Model No. Pipe size Fluid temp.
PSX2-B 1/2 4 in (V-mount) -40 +100℃
2 14 in (V)
PSX2-A -40 +100℃
12 16 in (Z)
2 14 in (V) +200℃
PSX2-HT -40
PUX2 12 16 in (Z)
2 16 in (V)
PSX2-E 12 48 in (Z) -40 +80℃
8 120 in (V)
PSX2-D 8 236 in (Z) -40 +80℃
SX2-A 1/2 4 in (V-mount) -40 +100℃
(V
2 14 in )
SX1-A 12 16 in (Z) -40 +80℃
2 14 in (V) +200℃
UXF3 SX2-B 12 16 in (Z) -40
2 24 in (V)
SX1-B 12 48 in (Z) -40 +80℃
8 120 in (V)
SX1-C 8 236 in (Z)
-40 +80℃

12. Accuracy – PUX2 & UXF3
 Rated accuracy PUX2, UXF3 :
Pipe diameter Velocity Accuracy Converter Sensor
Φ0.5 in. 2 to 32 m/s 1.5% of rate
to Φ 2 in. 0 to 2 m/s 0.03 m/s
• PSX
Φ2 in. to 2 to 32 m/s 1.0% of rate •PUX2
• SX1
Φ12 in. 0 to 2 m/s 0.02 m/s •UXF3
• SX2
Φ12 in.to 1 to 32 m/s 1.0% of rate
Φ24 in. + 0 to 1 m/s 0.01 m/s
 Reference conditions : +0.32
1. Fluid temp : Clean water 4 to 40℃
Accuracy [m/s]
2. Fluid pressure : Less than 1 MPa +0.02
+0.01
3. Flow : Full-filled, axisymmetric & well 0 1 2 32
developed turbulent flow -0.01
-0.02 Velocity
4. Warm-up time : 30 mins.
-0.32

13. Accuracy – UXF2
UXF2 Rated Accuracy
Plastic pipe
Pipe diameter Velocity Accuracy Converter Sensor
Φ1 in.to 2 to 10 m/s 2.5% of rate
Φ2 in. 0 to 2 m/s 0.05 m/s • UXF2 • SX3-A/B
• SX3-C/D
Φ2 in. to 2 to 10 m/s 1.5% of rate
Φ24 in. 0 to 2 m/s 0.03 m/s
Metal pipe
Pipe size Velocity Accuracy Converter Sensor
Φ2 in.to 2 to 10 m/s 2% of rate • UXF2 • SX3-A/B
Φ24 in 0 to 2 m/s 0.04 m/s • SX3-C/D

14. Getting Started – PUX2
Setting up
the model
PUX2
• Overview of functions

15. PUX2 Display & Screen navigation
• Interface divided among 6 selections To enter the “menu”
screen anytime, press the
• Default view = “measure” screen (below)
menu button
6 menu selections for
setup, configuration,
datalogger, printer, etc.
appear

16. Getting Started – UXF3
Setting up the
model UXF3
• Overview of functions

17. UXF3 – Inside the cover, wiring

18. UXF3 – Installation steps
 Basic Installation steps  Additional Installation steps
–Install Transmitter wiring and power –Install optional wiring
–Locate appropriate mounting location –Analog output, totalizer, switch outputs
–Set Inch or metric units –Program optional functions
–Program piping parameters –AO range
–Set main display preference & units –Totalizer
–Install sensor set on pipe –Flow switch/alarms
–Verify signal and reading –Low flow cutoff
–Damping
–Record system parameters
 4 key operation  Green/Red LED indicator on front panel

19. Getting Started – – UXF2
Getting Started UXF1
Setting up the
model UXF2
•Overview of functions
- 19 -

20. UXF2 – Primary components - inside
 Primary components & Functions
 Key input via front panel
 Modular 2 or 3 boards design
–Signal (bottom)
–Power supply (left top)Install Transmitter
wiring and power
–Serial comms (top right-optional)
 Front Panel LED
–Red/Green LED provides signal Normal or
error condition

21. UXF2 – Installation steps
jumper
 Basic Installation steps
–Install Transmitter wiring and power
–Locate appropriate mounting location
–Set Inch or metric units
–Program piping parameters
–Set main display preference & units
–Install sensor set on pipe
–Verify signal and reading
–Recommend Hardcopy of Manual Pages 40-42
 Additional Installation steps
–Install optional wiring
–Analog output, totalizer, switch outputs
–Program optional functions
–AO range
–Totalizer
–Flow switch/alarms
–Low flow cutoff
–Damping
–Record system parameters

22. Markets & Applications
• PUX2 and UXF3
– Wastewater flow monitoring in wastewater treatment systems and plants
– Water flow monitoring at water treatment plants
• UXF2
– Semiconductor – water flow monitoring
– Building Automation Systems
• Hot and cold water flow from chillers and boilers
• PUX2
– Building Automation Systems
• BTU Calculations
• In general good for flow monitoring when selling on the advantage of not
having to cut open the pipe for installation and also for repair work

23. Markets & Applications – PUX2 as an Energy Meter for BAS

24. Markets & Applications – PUX2 Installation

25. Questions
To order a free catalog or for more information contact;
Dwyer Instruments, Inc., P.O. Box 373,
Michigan City, IN., 46361
Telephone: (800) 872-9141 or (219) 879-8000
Fax: (219) 872-9057
Internet address: www.dwyer-inst.com
E-mail: info@dwyer-inst.com