Omega Products FDT-40 Installation Manual

1 YEAR

®

WARRANTY

User’s Guide

omega.com

e-mail: [e-mail]

For latest product manuals:

omegamanual.info

FDT-40 and FDT-40E Series

Transit Time Ultrasonic Flow Meter

OMEGAnet®Online Service Internet e-mail

omega.com [e-mail]

Servicing North America:

U.S.A.: Omega Engineering, Inc., One Omega Drive, P.O. Box 4047

ISO 9001 Certied Stamford, CT 06907-0047 USA

Toll Free: 1-800-826-6342 TEL: [phone]
FAX: [phone] e-mail: [e-mail]

Canada: 976 Bergar

Laval (Quebec), Canada H7L 5A1
Toll-Free: 1-800-826-6342 TEL: [phone]
FAX: [phone] e-mail: [e-mail]

For immediate technical or application assistance:

U.S.A. and Canada: Sales Service: 1-800-826-6342/1-800-TC-OMEGA

Customer Service: 1-800-622-2378/1-800-622-BEST
Engineering Service: 1-800-872-9436/1-800-USA-WHEN

Mexico: En Español: 001 [phone] FAX: [phone]

[e-mail] e-mail: [e-mail]

®

®

®

Servicing Europe:

Benelux: Managed by the United Kingdom Office

Toll-Free: 0800 099 3344 TEL: [phone]
FAX: [phone] e-mail: [e-mail]

Czech Republic: Frystatska 184

733 01 Karviná, Czech Republic
Toll-Free: 0800-1-66342 TEL: [phone]
FAX: [phone] e-mail: [e-mail]

France: Managed by the United Kingdom Office

Toll-Free: 0800 466 342 TEL: [phone]
FAX: [phone] e-mail: [e-mail]

Germany/Austria: Daimlerstrasse 26

D-75392 Deckenpfronn, Germany
Toll-Free: 0 800 6397678 TEL: [phone]
FAX: [phone] e-mail: [e-mail]

United Kingdom: OMEGA Engineering Ltd.

ISO 9001 Certied One Omega Drive, River Bend Technology Centre, Northbank

Irlam, Manchester M44 5BD England
Toll-Free: 0800-488-488 TEL: [phone]
FAX: [phone] e-mail: [e-mail]

It is the policy of OMEGA Engineering, Inc. to comply with all worldwide safety and EMC/EMI
regulations that apply. OMEGA is constantly pursuing certification of its products to the European New
Approach Directives. OMEGA will add the CE mark to every appropriate device upon certification.

The information contained in this document is believed to be correct, but OMEGA accepts no liability for any
errors it contains, and reserves the right to alter specifications without notice.
WARNING: These products are not designed for use in, and should not be used for, human applications.

TABLE OF CONTENTS

QUICKSTART OPERATING INSTRUCTIONS ...................................................................8

1 - Transducer Location ...........................................................................................................................8

2 - Electrical Connections ........................................................................................................................9

3 - Pipe Preparation and Transducer Mounting ......................................................................................9

4 - Startup ..............................................................................................................................................10

INTRODUCTION ..............................................................................................................11

General...................................................................................................................................................11

Application Versatility ...........................................................................................................................11

CE Compliance .......................................................................................................................................12

User Safety .............................................................................................................................................12

Data Integrity ........................................................................................................................................12

Product Identi cation ............................................................................................................................12

PART 1  TRANSMITTER INSTALLATION........................................................................13

Transducer Connections ........................................................................................................................14

Line Voltage AC Power Connections .....................................................................................................15

Low Voltage AC Power Connections ......................................................................................................15

DC Power Connections ..........................................................................................................................16

PART 2  TRANSDUCER INSTALLATION ........................................................................17

General...................................................................................................................................................17

Step 1 - Mounting Location ...................................................................................................................17

Step 2 - Transducer Spacing ..................................................................................................................19

Step 3 - Entering Pipe and Liquid Data .................................................................................................21

Step 4 - Transducer Mounting ...............................................................................................................22

V-Mount and W-Mount Installation ......................................................................................................23

FDT-41 through FDT-46/FDT-41-HT through FDT-46-HT Small Pipe Transducer Installation .............24

Mounting Transducers in Z-Mount Con guration ................................................................................26

Mounting Track Installation ..................................................................................................................28

PART 3  INPUTS/OUTPUTS ............................................................................................29

General...................................................................................................................................................29

4-20 mA Output .....................................................................................................................................29

Control Outputs  ow Only version].......................................................................................................30

Optional Totalizing Pulse Speci cations...............................................................................................32

Frequency Output [ ow only units] .......................................................................................................33

RS485 .....................................................................................................................................................35

Heat Flow for energy units only ............................................................................................................36

3

PART 4  STARTUP AND CONFIGURATION ....................................................................39

Before Starting the Instrument .............................................................................................................39

Instrument Startup ................................................................................................................................39

Keypad Programming ...........................................................................................................................40

Menu Structure ......................................................................................................................................41

BSC Menu -- Basic Menu.........................................................................................................................41

CH1 Menu -- Channel 1 Menu ................................................................................................................52

CH2 Menu -- Channel 2 Menu ................................................................................................................54

SEN Menu -- Sensor Menu ......................................................................................................................56

SEC Menu -- Security Menu ....................................................................................................................57

SER Menu -- Service Menu .....................................................................................................................58

DSP Menu -- Display Menu ....................................................................................................................62

PART 5  SOFTWARE UTILITY .........................................................................................64

Introduction ...........................................................................................................................................64

System Requirements ............................................................................................................................64

Installation.............................................................................................................................................64

Initialization ..........................................................................................................................................64

Basic Tab ................................................................................................................................................66

Flow Tab .................................................................................................................................................68

Filtering Tab ...........................................................................................................................................71

Output Tab .............................................................................................................................................73

Channel 1 - 4-20 mA Con guration .......................................................................................................73

Channel 2 - RTD Con guration [for energy units Only] ........................................................................75

Channel 2 - Control Output Con guration Flow Only ..........................................................................76

Setting Zero and Calibration .................................................................................................................79

Target Dbg Data Screen - De nitions ....................................................................................................82

Saving Meter Con guration on a PC .....................................................................................................83

Printing a Flow Meter Con guration Report ........................................................................................83

APPENDIX ........................................................................................................................84

Speci cations .........................................................................................................................................85

Menu Maps ............................................................................................................................................86

Communications Protocols ...................................................................................................................90

Protocol Implementation Conformance Statement (Normative) ........................................................96

Heating and Cooling Measurement ......................................................................................................98

FDT-40 Error Codes ..............................................................................................................................103

Control Drawings .................................................................................................................................104

Brad Harrison® Connector Option .......................................................................................................110

K-Factors Explained .............................................................................................................................111

Fluid Properties ...................................................................................................................................114

Symbol Explanations ...........................................................................................................................116

CE Compliance Drawings ....................................................................................................................116

4

FIGURES

Figure Q.1 - Transducer Mounting Con gurations .................................................................................8

Figure Q.2 - Transducer Connections ......................................................................................................9

Figure 1.1 - Ultrasound Transmission ...................................................................................................11

Figure 1.2 - FDT-40 Transmitter Dimensions .........................................................................................13

Figure 1.3 - Transducer Connections .....................................................................................................14

Figure 1.4 - AC Power Connections ........................................................................................................15

Figure 1.5 - 24 VAC Power Connections .................................................................................................15

Figure 1.6 - DC Power Connections .......................................................................................................16

Figure 2.1- Transducer Mounting Modes — FDT-47, FDT-48, and FDT-47-HT ......................................20

Figure 2.2 - Transducer Orientation — Horizontal Pipes......................................................................22

Figure 2.3 - Transducer Alignment Marks .............................................................................................23

Figure 2.4 - Application of Couplent .....................................................................................................23

Figure 2.5 - Transducer Positioning .......................................................................................................24

Figure 2.6 - Application of Acoustic Couplent — FDT-41 through FDT-46/FDT-41-HT through FDT-46-

HT Transducers ......................................................................................................................................25

Figure 2.7 - Data Display Screen ...........................................................................................................25

Figure 2.8 - Calibration Page 3 of 3 .......................................................................................................25

Figure 2.9 - Calibration Points Editor ....................................................................................................25

Figure 2.10 - Edit Calibration Points .....................................................................................................26

Figure 2.11 - Paper Template Alignment ..............................................................................................27

Figure 2.12 - Bisecting the Pipe Circumference ....................................................................................27

Figure 2.14 - Mounting Track Installation .............................................................................................28

Figure 2.13 - Z-Mount Transducer Placement .......................................................................................28

Figure 3.1 - Allowable Loop Resistance (DC Powered Units) ................................................................29

Figure 3.2 - 4-20 mA Output ..................................................................................................................30

Figure 3.3 - Switch Settings ...................................................................................................................30

Figure 3.4 - Typical Control Connections ..............................................................................................31

Figure 3.5 - Single Point Alarm Operation ............................................................................................31

Figure 3.6 - Energy version Totalizer Output Option ............................................................................32

Figure 3.7 - Frequency Output Switch Settings .....................................................................................33

Figure 3.8 - Frequency Output Waveform (Simulated Turbine) ...........................................................34

Figure 3.9 - Frequency Output Waveform (Square Wave) ....................................................................34

Figure 3.10 - RS485 Network Connections ............................................................................................35

Figure 3.12 - Surface Mount RTD Installation .......................................................................................36

Figure 3.11 - RTD Schematic ..................................................................................................................36

Figure 3.14 - Connecting RTDs ..............................................................................................................37

Figure 3.13 - Insertion Style RTD Installation .......................................................................................37

Figure 3.15 - Ultrasonic Energy - RTD Adapter Connections ................................................................38

Figure 4.1 - Keypad Interface.................................................................................................................40

5

Figure 5.1 - Data Display Screen ...........................................................................................................65

Figure 5.2 - Basic Tab .............................................................................................................................67

Figure 5.3 - Flow Tab ..............................................................................................................................69

Figure 5.4 - Filtering Tab ........................................................................................................................71

Figure 5.5 - Output Tab ..........................................................................................................................73

Figure 5.6 - Channel 2 Input (RTD) ........................................................................................................76

Figure 5.7 - Channel 2 Output Choices ..................................................................................................77

Figure 5.8 - Calibration Page 1 of 3 .......................................................................................................79

Figure 5.9 - Calibration Page 2 of 3 .......................................................................................................80

Figure 5.10 - Calibration Page 3 of 3 .....................................................................................................81

Figure A-2.1 - Menu Map -- 1 .................................................................................................................87

Figure A-2.2 - Menu Map -- 2 .................................................................................................................88

Figure A-2.3 - Menu Map -- 3 .................................................................................................................89

Figure A-4.1 - Output Con guration Screen .........................................................................................99

Figure A-4.2 - RTD Calibration (Step 1 of 2) ........................................................................................100

Figure A-4.3 - RTD Calibration (Step 2 of 2) ........................................................................................101

Figure A-6.1 - Control Drawing I.S. Barrier FDT-47 Transducers ........................................................104

Figure A-6.2 - Control Drawing I.S. Barrier FDT-47 Transducers Flexible Conduit .............................105

Figure A-6.3 - Control Drawing Ultrasonic Flow (Class 1, Div II) .........................................................106

Figure A-6.4 - Control Drawing (Class 1, Div II DC) .............................................................................107

Figure A-6.5 - FDT-40 (AC) Hazardous Area Installation ....................................................................108

Figure A-6.6 - FDT-40 (DC) Hazardous Area Installation ....................................................................109

Figure A-7.1 - Brad Harrison® Connections .........................................................................................110

Figure A-11.1 - CE Compliance Drawing For AC Powered Meters .......................................................122

Figure A-11.2 - CE Compliance Drawing For DC Powered Meters ......................................................123

6

TABLES

Table 2.1 - Piping Con guration and Transducer Positioning ..............................................................18

Table 2.2 - Transducer Mounting Modes — FDT-47, FDT-48, and FDT-47-HT ......................................19

Table 2.3 - Transducer Mounting Modes — FDT-41 through FDT-46 / FDT-41-HT through FDT-46-HT

................................................................................................................................................................20

Table 3.1 - Dip Switch Functions ............................................................................................................30

Table 4.1 - Speci c Heat Capacity Values for Water ..............................................................................47

Table 4.2 - Speci c Heat Capacity Values for Other Common Fluids ....................................................48

Table 4.3 - Speci c Heat Capacity Values for Ethylene Glycol/Water ...................................................48

Table 4.4 - Exponent Values ...................................................................................................................50

Table 4.5 - RTDs ......................................................................................................................................54

Table 4.6 - Sound Speed of Water ..........................................................................................................58

Table 4.7 - Sample Substitute Flow Readings .......................................................................................60

Table 5.1 - Transducer Frequencies .......................................................................................................67

Table A-3.1 - Available Data Formats ....................................................................................................90

Table A-3.2 - Flow Meter MODBUS Register Map for ‘Little-endian’ Word Order Master Devices .......91

Table A-3.3 - Flow Meter MODBUS Register Map for ‘Big-endian’ Word Order Master Devices ..........91

Table A-3.4 - MODBUS Coil Map ............................................................................................................91

Table A-3.5 - Flow Meter BACnet® Object Mappings .............................................................................92

Table A-3.6 - BACnet® Standard Objects ...............................................................................................95

Table A-4.1 - Heat Capacity of Water ..................................................................................................102

Table A-4.2 - Standard RTD Resistance Values ....................................................................................102

Table A-5.1 - Flow Meter Error Codes ..................................................................................................103

Table A-5.2 - Electrical Symbols ...........................................................................................................103

Table A-8.1 - Fluid Properties ..............................................................................................................115

Table A-10.1 - ANSI Pipe Data ..............................................................................................................117

Table A-10.2 - ANSI Pipe Data ..............................................................................................................118

Table A-10.3 - Tube Data .....................................................................................................................119

Table A-10.4 - Ductile Iron Pipe Data ..................................................................................................120

Table A-10.5 - Cast Iron Pipe Data .......................................................................................................121

7

QUICKSTART OPERATING INSTRUCTIONS

This manual contains detailed operating instructions for all aspects of the  ow metering instrument.
The following condensed instructions are provided to assist the operator in getting the instrument
started up and running as quickly as possible. This pertains to basic operation only. If speci c instrument
features are to be used or if the installer is unfamiliar with this type of instrument, refer to the appro­priate section in the manual for complete details.

NOTE: The following steps require information supplied by the meter itself so it will be necessary to supply power to the unit, at
least temporarily, to obtain setup information.

1  TRANSDUCER LOCATION

1) In general, select a mounting location on the piping system with a minimum of 10 pipe diameters
(10 × the pipe inside diameter) of straight pipe upstream and 5 straight diameters downstream.
See Table 2.1 for additional con gurations.

2) If the application requires FDT-47, FDT-48 or FDT-47-HT transducers select a mounting method for
the transducers based on pipe size and liquid characteristics. See Table 2.2. Transducer con gura-
tions are illustrated in Figure Q.1 below.

NOTE: All FDT-41 through FDT-46 and FDT-41-HT through FDT-46-HT transducers use V-Mount con guration.

3) Enter the following data into the transmitter via the integral keypad or the software utility:

1. Transducer mounting method 7. Pipe liner thickness

2. Pipe O.D. (Outside Diameter) 8. Pipe liner material

3. Pipe wall thickness 9. Fluid type

4. Pipe material 10. Fluid sound speed*

5. Pipe sound speed* 11. Fluid viscosity*

6. Pipe relative roughness* 12. Fluid speci c gravity*

* NOMINAL VALUES FOR THESE PARAMETERS ARE INCLUDED WITHIN THE FDT40 OPERATING SYSTEM. THE
NOMINAL VALUES MAY BE USED AS THEY APPEAR OR MAY BE MODIFIED IF THE EXACT SYSTEM VALUES ARE KNOWN.

TOP VIEW

OF PIPE

TOP VIEW

OF PIPE

TOP VIEW

OF PIPE

W-Mount V-Mount Z-Mount

FIGURE Q.1  TRANSDUCER MOUNTING CONFIGURATIONS

4) Record the value calculated and displayed as Transducer Spacing (XDC SPAC).

8

2  ELECTRICAL CONNECTIONS

TRANSDUCER/POWER CONNECTIONS

1) Route the transducer cables from the transducer mounting location back to the  ow meter
enclosure. Connect the transducer wires to the terminal block in the  ow meter enclosure.

2) Verify that power supply is correct for the meters

Downstream+
Downstream­Upstream­Upstream+

power option.

Line voltage AC units require 95 to 265 VAC
47 to 63 Hz @ 17 VA maximum.

Low voltage AC units require 20 to 28 VAC
47 to 63 Hz @ 0.35 A maximum.

FIGURE Q.2  TRANSDUCER CONNECTIONS

3) Connect power to the  ow meter.

DC units require 10 to 28 VDC @ 5 Watts maximum.

3  PIPE PREPARATION AND TRANSDUCER MOUNTING

(FDT-47, FDT-48, and FDT-47-HT Transducers)

1) Place the  ow meter in signal strength measuring mode. This value is available on the  ow meters
display (Service Menu) or in the data display of the software utility.

2) The pipe surface, where the transducers are to be mounted, must be clean and dry. Remove scale,
rust or loose paint to ensure satisfactory acoustic conduction. Wire brushing the rough surfaces
of pipes to smooth bare metal may also be useful. Plastic pipes do not require preparation other
than cleaning.

3) Apply a single ½” (12 mm) bead of acoustic couplent grease to the upstream transducer and
secure it to the pipe with a mounting strap.

4) Apply acoustic couplent grease to the downstream transducer and press it onto the pipe using
hand pressure at the lineal distance calculated in Step 1.

5) Space the transducers according to the recommended values found during programming or from
the software utility. Secure the transducers with the mounting straps at these locations.

9

(FDT-41 through FDT-46 and FDT-41-HT through FDT-46-HT Transducers)

1) Place the  ow meter in signal strength measuring mode. This value is available on the  ow
meter’s display (Service Menu) or in the data display of the software utility.

2) The pipe surface, where the transducers are to be mounted, must be clean and dry. Remove scale,
rust or loose paint to ensure satisfactory acoustic conduction. Wire brushing the rough surfaces
of pipes to smooth bare metal may also be useful. Plastic pipes do not require preparation other
than cleaning.

3) Apply a single ½” (12 mm) bead of acoustic couplent grease to the top half of the transducer and
secure it to the pipe with bottom half or U-bolts.

4) Tighten the nuts so that the acoustic coupling grease begins to  ow out from the edges of the
transducer and from the gap between the transducer and the pipe. Do not over tighten.

4  STARTUP

INITIAL SETTINGS AND POWER UP

1) Apply power to the transmitter.

2) Verify that SIG STR is greater than 5.0.

3) Input proper units of measure and I/O data.

10

INTRODUCTION

GENERAL

This transit time ultrasonic  ow meter is designed to measure the  uid velocity of liquid within a closed
conduit. The transducers are a non-contacting, clamp-on type or clamp-around, which will provide
bene ts of non-fouling operation
and ease of installation.

TOP VIEW

OF PIPE

TOP VIEW

OF PIPE

This family of transit time  ow
meters utilize two transducers
that function as both ultrasonic

W-Mount V-Mount Z-Mount

transmitters and receivers. The
transducers are clamped on the

FIGURE 1.1  ULTRASOUND TRANSMISSION

outside of a closed pipe at a speci c distance from each other. The transducers can be mounted in
V-Mount where the sound transverses the pipe two times, W-Mount where the sound transverses the

pipe four times, or in Z-Mount where the transducers are mounted on opposite sides of the pipe and the
sound crosses the pipe once. The selection of mounting method is based on pipe and liquid characteris­tics which both have an e ect on how much signal is generated. The  ow meter operates by alternately
transmitting and receiving a frequency modulated burst of sound energy between the two transducers
and measuring the time interval that it takes for sound to travel between the two transducers. The di er­ence in the time interval measured is directly related to the velocity of the liquid in the pipe.

TOP VIEW

OF PIPE

APPLICATION VERSATILITY

This  ow meter can be successfully applied on a wide range of metering applications. The simple-to­program transmitter allows the standard product to be used on pipe sizes ranging from ½ inch to 100
inches (12 mm to 2540 mm)*. A variety of liquid applications can be accommodated:

ultrapure liquids cooling water
potable water river water
chemicals plant e uent
sewage others
reclaimed water

Because the transducers are non-contacting and have no moving parts, the  ow meter is not a ected
by system pressure, fouling or wear. Standard transducers, FDT-47 and FDT-48 are rated to a pipe surface
temperature of -40 to +250 °F (-40 to +121 °C). FDT-41 through FDT-46 small pipe transducers are rated
from -40 to +185 °F (-40 to +85 °C). The FDT-47-HT high temperature transducers can operate to a pipe
surface temperature of -40 to +350 °F (-40 to +176 °C) and the FDT-41-HT through FDT-46-HT small pipe
high temperature transducer will withstand temperature of -40 to +250 °F (-40 to +121 °C).

*ALL ½” TO 1½” SMALL PIPE TRANSDUCERS AND 2” SMALL PIPE TUBING TRANSDUCER SETS REQUIRE THE TRANS
MITTER BE CONFIGURED FOR 2 MHz AND USE DEDICATED PIPE TRANSDUCERS. FDT48 TRANSDUCERS REQUIRE THE
USE OF THE 500 KH
THE SOFTWARE UTILITY OR THE TRANSMITTER’S KEYPAD.

Z TRANSMISSION FREQUENCY. THE TRANSMISSION FREQUENCY IS SELECTABLE USING EITHER

11

CE COMPLIANCE

The transmitter can be installed in conformance to CISPR 11 (EN 55011) standards. See the CE Compli­ance drawings in the Appendix of this manual.

USER SAFETY

This meter employs modular construction and provides electrical safety for the operator. The display
face contains voltages no greater than 28 VDC. The display face swings open to allow access to user
connections.

Danger: The power supply board can have line voltages applied to it, so disconnect electrical
power before opening the instrument enclosure. Wiring should always conform to local codes
and the National Electrical Code®.

DATA INTEGRITY

Non-volatile  ash memory retains all user-entered con guration values in memory for several years at
77 °F (25 °C), even if power is lost or turned o . Password protection is provided as part of the Security
menu (SEC MENU) and prevents inadvertent con guration changes or totalizer resets.

PRODUCT IDENTIFICATION

The serial number and complete model number of the transmitter are located on the top outside surface
of the transmitter’s body. Should technical assistance be required, please provide the Customer Service
Department with this information.

12

PART 1  TRANSMITTER INSTALLATION

4.32

(109.7)

4.20

(106.7)

2.06

(52.3)

6.00

(152.4)

After unpacking, it is recommended to save the shipping carton and packing materials in case the instru­ment is stored or re-shipped. Inspect the equipment and carton for damage. If there is evidence of ship­ping damage, notify the carrier immediately.

The enclosure should be mounted in an area that is convenient for servicing, calibration or for observa­tion of the LCD readout.

1) Locate the transmitter within the length of transducer cables supplied. If this is not possible, it is
recommended that the cable be exchanged for one that is of proper length. To add cable length
to a transducer, the cable must be the same type as utilized on the transducer. Twinaxial cables
can be lengthened with like cable to a maximum overall length of 100 feet (30 meters). Coaxial
cables can be lengthened with RG59 75 Ohm cable and BNC connectors to 990 feet (300 meters).

2) Mount the transmitter in a location:

~ Where little vibration exists.

~

That is protected from corrosive  uids.

~ That is within the transmitters ambient temperature limits -40 to +185 °F (-40 to +85 °C).
~ That is out of direct sunlight. Direct sunlight may increase transmitter

temperature to above the maximum limit.

3) Mounting - Refer to Figure 1.2 for enclosure and mounting dimension
details. Ensure that enough room is available to allow for door swing, main­tenance and conduit entrances.
Secure the enclosure to a  at
surface with two appropriate
fasteners.

4) Conduit Holes - Conduit holes
should be used where cables
enter the enclosure. Holes not
used for cable entry should be
sealed with plugs.

An optional cable gland kit is
available for inserting trans­ducer and power cables. The
manufacturers part number for
this kit is FDT-40-Cable Gland
Kit and can be ordered directly
from the manufacturer.

NOTE: Use NEMA 4 [IP-65] rated  ttings/plugs to maintain the watertight integrity of the enclosure. Generally, the right conduit
hole (viewed from front) is used for power, the left conduit hole for transducer connections, and the center hole is utilized for I/O
wiring.

FIGURE 1.2  FDT40 TRANSMITTER DIMENSIONS

13

TRANSDUCER CONNECTIONS

To access terminal strips for wiring, loosen the two screws in the enclosure door and open.

Guide the transducer terminations through the transmitter conduit hole located in the bottom-left of
the enclosure. Secure the transducer cable with the supplied conduit nut (if  exible conduit was ordered
with the transducer).

The terminals within  ow meter are of a
screw-down barrier terminal type. Connect
the appropriate wires at the corresponding
screw terminals in the transmitter. Observe
upstream and downstream orientation
and wire polarity. See Figure 1.3.

O

N

1234

RS485 Gnd

RS485 A(-)

RS485 B(+)

Reset Total

4-20 mA Out

Frequency Out

Control 2

Control 1

Signal Gnd.

95 - 264 VAC

AC Neutral

372

VE
D

1500mA250V

C US

R

W

NOTE: Transducer cables have two possible wire
colors. For the blue and white combination the blue
wire is positive (+) and the white wire is negative (-).
For the red and black combination the red wire is

+

+

Downstream

Downstream

-

-

-

-

Upstream

Upstream

+

+

TFX Tx

Modbus

TFX Rx

positive (+) and the black wire is negative (-).

NOTE: The transducer cable carries low level, high
frequency signals. In general, it is not recommended
to add additional length to the cable supplied with
the transducers. Cables 100 to 990 feet (30 to 300

To Transducers

meters) are available with RG59 75 Ohm coaxial
cable. If additional cable is added, ensure that
it is the same type as utilized on the transducer.

FIGURE 1.3  TRANSDUCER CONNECTIONS

Twinaxial (blue and white conductor) cables can be
lengthened with like cable to a maximum overall length of 100 feet (30 meters). Coaxial cables can be lengthened with RG59
75 Ohm cable and BNC connectors to 990 feet (300 meters).

Connect power to the screw terminal block in the transmitter. See Figure 1.4 and Figure 1.5. Utilize the
conduit hole on the right side of the enclosure for this purpose. Use wiring practices that conform to
local and national codes (e.g., The National Electrical Code® Handbook in the U.S.)

CAUTION

CAUTION: Any other wiring method may be unsafe or cause improper operation of the instrument.

NOTE: This instrument requires clean electrical line power. Do not operate this unit on circuits with noisy components (i.e.,
 uorescent lights, relays, compressors, or variable frequency drives). The use of step down transformers from high voltage, high
amperage sources is also not recommended. Do not to run signal wires with line power within the same wiring tray or conduit.

14

LINE VOLTAGE AC POWER
CONNECTIONS

Connect 90 to 265 VAC, AC Neutral and
Chassis Ground to the terminals referenced
in Figure 1.4. Do not operate without an
earth (chassis) ground connection.

LOW VOLTAGE AC POWER
CONNECTIONS

Connect 20 to 28 VAC, AC Neutral and
Chassis Ground to the terminals referenced
in Figure 1.5. Do not operate without an
earth (chassis) ground connection.

The 24 VAC power supply option for this
meter is intended for a typical HVAC and
Building Control Systems (BCS) powered
by a 24 VAC, nominal, power source. This
power source is provided by AC line power
to 24 VAC drop down transformer
and is installed by the installation
electricians.

NOTE: In electrically noisy applications,
grounding the meter to the pipe where
the transducers are mounted may provide
additional noise suppression. This approach
is only e ective with conductive metal
pipes. The earth (chassis) ground derived
from the line voltage power supply should
be removed at the meter and a new earth
ground connected between the meter and
the pipe being measured.

NOTE: Wire gauges up to 14 AWG can be
accommodated in the  ow meter terminal
blocks.

NOTE: AC powered versions are protected
by a  eld replaceable fuse. This fuse is
equivalent to Wickmann P.N. 3720500041 or

37405000410.

+Vo

-Vo

Modbus

TFX Rx
TFX Tx

Downstream

Upstream

-

-

+

+

372

VE

D

1500mA250V

W

C US

R

O

1234

N

ACN

ACL

95 - 264 VAC

95 - 264 VAC

AC Neutral

AC Neutral
Signal Gnd.
Control 1
Control 2
Frequency Out
4-20 mA Out
Reset Total
RS485 Gnd
RS485 A(-)
RS485 B(+)

FIGURE 1.4  AC POWER CONNECTIONS

ACN

1500mA250V

372

W

C US

VE

D

R

ACL

Chassis Gnd.
24 VAC
AC Neutral

Signal Gnd.
Control 1
Control 2
Frequency Out
4-20 mA Out
Reset Total
RS485 Gnd
RS485 A(-)
RS485 B(+)

Tes t

P1

O

1234

N

+Vo

-Vo

Modbus

TFX Rx
TFX Tx

Downstream

Upstream

-

-

+

+

24 VAC

Transformer

FIGURE 1.5  24 VAC POWER CONNECTIONS

15

DC POWER CONNECTIONS

The  ow meter may be operated from a 10
to 28 VDC source, as long as the source is
capable of supplying a minimum of 5 Watts
of power.

Connect the DC power to 10 to 28 VDC In,
Power Gnd., and Chassis Gnd., as in Figure

1.6.

NOTE: DC powered versions are protected by an

automatically resetting fuse. This fuse does not
require replacement.

O

1234

N

10 - 28 VDC

10 - 28 VDC

Power Gnd.

Power Gnd.
Signal Gnd.
Control 1
Control 2
Frequency Out
4-20 mA Out
Reset Total
RS485 Gnd
RS485 A(-)
RS485 B(+)

Modbus

TFX Rx
TFX Tx

Downstream

Upstream

-

-

+

+

Power

Ground

10 -28 VDC

FIGURE 1.6  DC POWER CONNECTIONS

16

PART 2  TRANSDUCER INSTALLATION

GENERAL

The transducers that are utilized by this  ow meter contain piezoelectric crystals for transmitting and
receiving ultrasonic signals through walls of liquid piping systems. FDT-47, FDT-48 and FDT-47-HT trans­ducers are relatively simple and straightforward to install, but spacing and alignment of the transducers
is critical to the system’s accuracy and performance. Extra care should be taken to ensure that these
instructions are carefully executed. FDT-41 through FDT-46 and FDT-41-HT through FDT-46-HT, small
pipe transducers, have integrated transmitter and receiver elements that eliminate the requirement for
spacing measurement and alignment.

Mounting of the FDT-47, FDT-48, and FDT-47-HT clamp-on ultrasonic transit time transducers is
comprised of three steps:

1) Selection of the optimum location on a piping system.

2) Entering the pipe and liquid parameters into either the software utility or keying the parameters
into transmitter using the keypad. The software utility or the transmitters  rmware will calculate
proper transducer spacing based on these entries.

3) Pipe preparation and transducer mounting.

Energy transmitters require two RTDs to measure heat usage. The  ow meter utilizes 1,000 Ohm, three­wire, platinum RTDs in two mounting styles. Surface mount RTDs are available for use on well insulated
pipes. If the area where the RTD will be located is not insulated, inconsistent temperature readings will
result and insertion (wetted) RTDs should be utilized.

STEP 1  MOUNTING LOCATION

The  rst step in the installation process is the selection of an optimum location for the  ow measure­ment to be made. For this to be done e ectively, a basic knowledge of the piping system and its
plumbing are required.

An optimum location is de ned as:

~ A piping system that is completely full of liquid when measurements are being taken. The pipe

may become completely empty during a process cycle – which will result in the error code 0010
(Low Signal Strength) being displayed on the  ow meter while the pipe is empty. This error code
will clear automatically once the pipe re lls with liquid. It is not recommended to mount the
transducers in an area where the pipe may become partially  lled. Partially  lled pipes will cause
erroneous and unpredictable operation of the meter.

~ A piping system that contains lengths of straight pipe such as those described in Table 2.1. The

optimum straight pipe diameter recommendations apply to pipes in both horizontal and vertical
orientation. The straight runs in Table 2.1 apply to liquid velocities that are nominally 7 FPS (2.2
MPS). As liquid velocity increases above this nominal rate, the requirement for straight pipe
increases proportionally.

~ Mount the transducers in an area where they will not be inadvertently bumped or disturbed

during normal operation.

~ Avoid installations on downward  owing pipes unless adequate downstream head pressure is

present to overcome partial  lling of or cavitation in the pipe.

17

Piping Configuration

and Transducer Positioning

Upstream

Pipe

Diameters

Downstream

Pipe

Diameters

***

Flow

Flow

Flow

Flow

24

*

**

14

*

**

10

*

**

10

*

**

5

5

5

5

Flow

*

Flow

*

TABLE 2.1  PIPING CONFIGURATION AND TRANSDUCER POSITIONING

This  ow meter system will provide repeatable measurements on piping systems that do not meet these
requirements, but accuracy of these readings may be in uenced to various degrees.

18

**

**

10

24

5

5

STEP 2  TRANSDUCER SPACING

The transmitter can be used with  ve di erent transducer types: FDT-47, FDT-48, FDT-47-HT, FDT-41
through FDT-46 and FDT-41-HT through FDT-46-HT. Meters that utilize the FDT-47, FDT-48, or FDT­47-HT transducer sets consist of two separate sensors that function as both ultrasonic transmitters and
receivers. FDT-41 through FDT-46 and FDT-41-HT through FDT-46-HT transducers integrate both the
transmitter and receiver into one assembly that  xes the separation of the piezoelectric crystals. FDT-47,
FDT-48, and FDT-47-HT transducers are clamped on the outside of a closed pipe at a speci c distance
from each other.

The FDT-47, FDT-48, and FDT-47-HT transducers can be mounted in:

W-Mount where the sound traverses the pipe four times. This mounting method produces the
best relative travel time values but the weakest signal strength.
V-Mount where the sound traverses the pipe twice. V-Mount is a compromise between travel
time and signal strength.
Z-Mount where the transducers are mounted on opposite sides of the pipe and the sound crosses
the pipe once. Z-Mount will yield the best signal strength but the smallest relative travel time.

Transducer Mount Mode Pipe Material Pipe Size Liquid Composition

Plastic (all types)

W-Mount

V-Mount

Z-Mount

Carbon Steel

2-4 in. (50-100 mm)

Stainless Steel
Copper
Ductile Iron

Not recommended

Cast Iron
Plastic (all types)

4-12 in. (100-300 mm)Carbon Steel

Stainless Steel

Low TSS; non-aerated

Copper 4-30 in. (100-750 mm)
Ductile Iron

2-12 in. (50-300 mm)

Cast Iron
Plastic (all types) > 30 in. (> 750 mm)
Carbon Steel

> 12 in. (> 300 mm)

Stainless Steel
Copper > 30 in. (> 750 mm)
Ductile Iron

> 12 in. (> 300 mm)

Cast Iron

TSS = Total Suspended Solids

TABLE 2.2  TRANSDUCER MOUNTING MODES  FDT47, FDT48, AND FDT47HT

19

For further details, reference Figure 2.1. The appropriate mounting con guration is based on pipe and
liquid characteristics. Selection of the proper transducer mounting method is not entirely predictable
and many times is an iterative process. Table 2.2 contains recommended mounting con gurations for
common applications. These recommended con gurations may need to be modi ed for speci c appli­cations if such things as aeration, suspended solids, out of round piping or poor piping conditions are
present. Use of the  ow meter diagnostics in determining the optimum transducer mounting is covered
later in this section.

TOP VIEW

OF PIPE

TOP VIEW

OF PIPE

TOP VIEW

OF PIPE

W-Mount V-Mount Z-Mount

FIGURE 2.1 TRANSDUCER MOUNTING MODES  FDT47, FDT48, AND FDT47HT

Size Frequency Setting Transducer Mounting Mode

FDT-41-ANSI FDT-41-ANSI-HT

½ 2 MHz

¾ 2 MHz

1 2 MHz

FDT-41-CP FDT-41-CP-HT
FDT-41-T FDT-41-T-HT
FDT-42-ANSI FDT-42-ANSI-HT
FDT-42-CP FDT-42-CP-HT
FDT-42-T FDT-42-T-HT
FDT-43-ANSI FDT-43-ANSI-HT
FDT-43-CP FDT-43-CP-HT
FDT-43-T FDT-43-T-HT
FDT-44-ANSI FDT-44-ANSI-HT

V

1¼ 2 MHz

FDT-44-CP FDT-44-CP-HT
FDT-44-T FDT-44-T-HT
FDT-45-ANSI FDT-45-ANSI-HT

1½ 2 MHz

FDT-45-CP FDT-45-CP-HT
FDT-45-T FDT-45-T-HT
FDT-46-ANSI FDT-46-ANSI-HT

1 MHz

2

FDT-46-CP FDT-46-CP-HT

2 MHz FDT-46-T FDT-46-T-HT

TABLE 2.3  TRANSDUCER MOUNTING MODES  FDT41 THROUGH FDT46 / FDT41HT THROUGH

FDT46HT

For pipes 24” (600 mm) and larger the FDT-48 transducers using a transmission frequency of 500 KHz are
recommended.

20

FDT-48 transducers may also be advantageous on pipes between 4” and 24” if there are less quanti able
complicating aspects such as – sludge, tuberculation, scale, rubber liners, plastic liners, thick mortar, gas
bubbles, suspended solids, emulsions, or pipes that are perhaps partially buried where a V-mount is
required/desired, etc.

STEP 3  ENTERING PIPE AND LIQUID DATA

This metering system calculates proper transducer spacing by utilizing piping and liquid information
entered by the user. This information can be entered via the keypad on the  ow meter or via the optional
software utility.

The best accuracy is achieved when transducer spacing is exactly what the  ow meter calculates, so
the calculated spacing should be used if signal strength is satisfactory. If the pipe is not round, the wall
thickness not correct or the actual liquid being measured has a di erent sound speed than the liquid
programmed into the transmitter, the spacing can vary from the calculated value. If that is the case, the
transducers should be placed at the highest signal level observed by moving the transducers slowly
around the mount area.

NOTE: Transducer spacing is calculated on “ideal” pipe. Ideal pipe is almost never found so the transducer spacing distances may
need to be altered. An e ective way to maximize signal strength is to con gure the display to show signal strength,  x one trans­ducer on the pipe and then starting at the calculated spacing, move the remaining transducer small distances forward and back
to  nd the maximum signal strength point.

Important! Enter all of the data on this list, save the data and reset the  ow meter before mounting
transducers.

The following information is required before programming the instrument:

Transducer mounting con guration Pipe O.D. (outside diameter)
Pipe wall thickness Pipe material
Pipe sound speed

1

Pipe relative roughness

1

Pipe liner thickness (if present) Pipe liner material (if present)
Fluid type Fluid sound speed
Fluid viscosity

NOTE: Much of the data relating to material sound speed, viscosity and speci c gravity is pre-programmed into the  ow meter.
This data only needs to be modi ed if it is known that a particular application’s data varies from the reference values. Refer to Part
4 of this manual for instructions on entering con guration data into the  ow meter via the transmitter’s keypad. Refer to Part 5
for data entry via the software.

1

NOMINAL VALUES FOR THESE PARAMETERS ARE INCLUDED WITHIN THE METERS OPERATING SYSTEM. THE NOMINAL VALUES

MAY BE USED AS THEY APPEAR OR MAY BE MODIFIED IF EXACT SYSTEM VALUES ARE KNOWN.

1

Fluid speci c gravity

1

1

After entering the data listed above, the  ow meter will calculate proper transducer spacing for the
particular data set. This distance will be in inches if the  ow meter is con gured in English units, or milli­meters if con gured in metric units.

21

STEP 4  TRANSDUCER MOUNTING

Pipe Preparation

After selecting an optimal mounting location (Step 1) and successfully determining the proper trans­ducer spacing (Step 2 & 3), the transducers may now be mounted onto the pipe (Step 4).

Before the transducers are mounted onto the pipe surface, an area slightly larger than the  at surface
of each transducer must be cleaned of all rust, scale and moisture. For pipes with rough surfaces, such
as ductile iron pipe, it is recommended that the pipe surface be wire brushed to a shiny  nish. Paint
and other coatings, if not  aked or bubbled, need not be removed. Plastic pipes typically do not require
surface preparation other than soap and water cleaning.

The FDT-47, FDT-48, and FDT-47-HT transducers must be properly oriented and spaced on the pipe to
provide optimum reliability and performance. On horizontal pipes, when Z-Mount is required, the trans­ducers should be mounted 180 radial degrees from one another and at least 45 degrees from the top­dead-center and bottom-dead-center of the pipe. See Figure 2.2. Also see

tion

. On vertical pipes the orientation is not critical.

The spacing between the transducers is measured between the two spacing marks on the sides of the
transducers. These marks are approximately 0.75” (19 mm) back from the nose of the FDT-47 and FDT­47-HT transducers, and 1.2” (30 mm) back from the nose of the FDT-48 transducers. See Figure 2.3.

FDT-41 through FDT-46 and FDT-41-HT through FDT-46-HT transducers should be mounted with the
cable exiting within ±45 degrees of the side of a horizontal pipe. See Figure 2.2. On vertical pipes the
orientation does not apply.

Z-Mount Transducer Installa-

45°

YES

45°

MOUNTING ORIENTATION

2” FDT-46 and FDT-46-HT

TOP OF

PIPE

FLOW METER

TRANSDUCERS

YES

45°

YES

45°

MOUNTING ORIENTATION

45°

45°

TOP OF

PIPE

FLOW METER

FDT-47, FDT-48,
and FDT-47-HT
TRANSDUCERS

45°

YES

45°

45°

YES

45°

FLOW METER

MOUNTING ORIENTATION

FDT-41through FDT-45

FDT-41-HT through FDT-45-HT

TRANSDUCERS

TOP OF

PIPE

45°

YES

45°

and

22

FIGURE 2.2  TRANSDUCER ORIENTATION  HORIZONTAL PIPES

Alignment

Marks

FIGURE 2.3  TRANSDUCER ALIGNMENT MARKS

VMOUNT AND WMOUNT INSTALLATION

Application of Couplent

For FDT-47, FDT-48, and FDT-47-HT transducers, place a single bead of couplent, approximately ½ inch
(12 mm) thick, on the  at face of the transducer. See Figure 2.4. Generally, a silicone-based grease is used
as an acoustic couplent, but any grease-like substance that is rated not to “ ow” at the temperature that
the pipe may operate at will be acceptable. For pipe surface temperature over 130 °F (55 °C), Sonotemp®
(FDT-HT-Grease) is recommended.

½”

(12 mm)

FIGURE 2.4  APPLICATION OF COUPLENT

Transducer Positioning

1) Place the upstream transducer in position and secure with a mounting strap. Straps should be
placed in the arched groove on the end of the transducer. A screw is provided to help hold the
transducer onto the strap. Verify that the transducer is true to the pipe and adjust as necessary.
Tighten the transducer strap securely.

2) Place the downstream transducer on the pipe at the calculated transducer spacing. See Figure

2.5. Apply  rm hand pressure. If signal strength is greater than 5, secure the transducer at this
location. If the signal strength is not 5 or greater, using  rm hand pressure slowly move the trans­ducer both towards and away from the upstream transducer while observing signal strength.

NOTE: Signal strength readings update only every few seconds, so it is advisable to move the transducer ⁄”, wait, see if signal is
increasing or decreasing and then repeat until the highest level is achieved.

23

Signal strength can be displayed on the  ow
meter’s display or on the main data screen in
the software utility. See Part 5 of this manual
for details regarding the software utility. Clamp
the transducer at the position where the highest
signal strength is observed. The factory default
signal strength setting is 5, however there are
many application speci c conditions that may
prevent the signal strength from attaining this
level. Signal levels less than 5 will probably not
be acceptable for reliable readings.

3) If after adjustment of the transducers the signal
strength does not rise to above 5, then an alter­nate transducer mounting method should be
selected. If the mounting method was W-Mount,
then re-con gure the transmitter for V-Mount,
move the downstream transducer to the new
spacing distance and repeat Step 4.

NOTE: Mounting of high temperature transducers is similar to
mounting the FDT-47/FDT-48 transducers. High temperature instal­lations require acoustic couplent that is rated not to “ ow” at the
temperature that will be present on the pipe surface.

NOTE: As a rule, the FDT-48 should be used on pipes 24” and larger
and not used for application on a pipe smaller than 4”. Consider
application of the FDT-48 transducers on pipes smaller than 24” if there are less quanti able aspects such as - sludge, tubercula­tion, scale, rubber liners, plastic liners, thick mortar liners, gas bubbles, suspended solids, emulsions, and smaller pipes that are
perhaps partially buried where a V-Mount is required/desired, etc.

FIGURE 2.5  TRANSDUCER POSITIONING

Spacing

FDT41 THROUGH FDT46/FDT41HT THROUGH FDT46HT SMALL PIPE TRANS
DUCER INSTALLATION

The small pipe transducers are designed for speci c pipe outside diameters. Do not attempt to mount a
FDT-41 through FDT-46/FDT-41-HT through FDT-46-HT transducer onto a pipe that is either too large or
too small for the transducer. Contact the manufacturer to arrange for a replacement transducer that is
the correct size.

FDT-41 through FDT-46/FDT-41-HT through FDT-46-HT installation consists of the following
steps:

Transducer

1) Apply a thin coating of acoustic coupling grease to both halves of the transducer housing where
the housing will contact the pipe. See Figure 2.6.

2) On horizontal pipes, mount the transducer in an orientation such that the cable exits at ±45
degrees from the side of the pipe. Do not mount with the cable exiting on either the top or
bottom of the pipe. On vertical pipes the orientation does not matter. See Figure 2.2.

3) Tighten the wing nuts or “U” bolts so that the acoustic coupling grease begins to  ow out from the
edges of the transducer or from the gap between the transducer halves. Do not over tighten.

4) If signal strength is less than 5, remount the transducer at another location on the piping system.

24

⁄” (1.5 mm)

30.00

000.00 Gal/

000

Acoustic Couplant

Grease

FIGURE 2.6  APPLICATION OF ACOUSTIC COUPLENT  FDT41 THROUGH FDT46/FDT41HT

THROUGH FDT46HT TRANSDUCERS

NOTE: If a FDT-41 through FDT-46/FDT-41-HT through FDT-46-HT small pipe transducer was purchased separately from the  ow

meter, the following con guration procedure is required.

FDT-41 through FDT-46/FDT-41-HT through FDT-46-HT Small Pipe Transducer Con guration
Procedure

1) Establish communications with the transit
time meter. See Part 5 - Software Utility.

2) From the Tool Bar select Calibration. See
Figure 2.7.

3) On the pop-up screen, click Next button
twice to get to Page 3 of 3. See Figure 2.8.

Device Addr 127

HelpWindowCommunicationsViewEditFile

!

Configuration CalibrationStrategy

Device Addr 127

Errors

Print PreviePrint

Scale:60 MinTime:

Calibration (Page 3 of 3) - Linearization

28.2

Gal/M

200

Delta Time

1) Please establish a
reference flow rate.

1FPS / 0.3MPS Minimum.

2) Enter the reference flow
rate below. (Do not enter 0)

3) Wait for flow to stabilize.

4) Press the Set button.

Flow:

Set

Edit

Export...

Flow:

Totalizer Net:

Pos:

Neg:

Sig. Strength:

Margin:

Delta T:

Last Update:

1350 Gal/Min
0 OB
0 OB
0 OB

15.6%
100%

-2.50 ns
09:53:39

2000

1600

1200

FIGURE 2.7  DATA DISPLAY SCREEN

4) Click Edit.

5) If calibration point is displayed in Calibration
Points Editor screen, record the information,
highlight and click Remove. See Figure 2.9.

6) Click ADD...

7) Enter Delta T, Un-calibrated Flow, and Cali­brated Flow values from the FDT-41 through
FDT-46/FDT-41-HT through FDT-46-HT cali­bration label, the click OK. See Figure 2.10.

FIGURE 2.8  CALIBRATION PAGE 3 OF 3

Calibration Points Editor

Select point(s) to edit or remove:

30.00 ns 2000.00 Gal/Min 1.000

ns 2

OK

Min 1.

Cancel

FIGURE 2.9  CALIBRATION POINTS EDITOR

Add...

Edit...

Remove

Select All

Select All

Select None

Select None

25

8) Click OK in the Edit Calibration Points
screen.

9) Process will return to Page 3 of 3. Click
Finish. See Figure 2.8.

10) After “Writing Con guration File” is
complete, turn power o . Turn on again
to activate new settings.

Model: FDT-45-ANSI
S/N: 12345 Delta-T: 391.53nS

Uncal. Flow: 81.682 GPM

Cal. Flow: 80 GPM

Edit Calibration Points

Delta T:

Uncalibrated Flow:

Calibrated Flow:

OK

391.53

81.682

80.000

ns

Gal/Min.

Gal/Min.

Cancel

MOUNTING TRANSDUCERS IN

FIGURE 2.10  EDIT CALIBRATION POINTS

ZMOUNT CONFIGURATION

Installation on larger pipes requires careful measurements of the linear and radial placement of the
FDT-47, FDT-48, and FDT-47-HT transducers. Failure to properly orient and place the transducers on the
pipe may lead to weak signal strength and/or inaccurate readings. This section details a method for
properly locating the transducers on larger pipes. This method requires a roll of paper such as freezer
paper or wrapping paper, masking tape and a marking device.

1) Wrap the paper around the pipe in the manner shown in Figure 2.11. Align the paper ends to
within ¼ inch (6 mm).

2) Mark the intersection of the two ends of the paper to indicate the circumference. Remove the
template and spread it out on a  at surface. Fold the template in half, bisecting the circumfer­ence. See Figure 2.12.

3) Crease the paper at the fold line. Mark the crease. Place a mark on the pipe where one of the
transducers will be located. See Figure 2.2 for acceptable radial orientations. Wrap the template
back around the pipe, placing the beginning of the paper and one corner in the location of the
mark. Move to the other side of the pipe and mark the pipe at the ends of the crease. Measure
from the end of the crease (directly across the pipe from the  rst transducer location) the dimen­sion derived in Step 2, Transducer Spacing. Mark this location on the pipe.

4) The two marks on the pipe are now properly aligned and measured.

If access to the bottom of the pipe prohibits the wrapping of the paper around the circumfer­ence, cut a piece of paper ½ the circumference of the pipe and lay it over the top of the pipe. The
length of ½ the circumference can be found by:

½ Circumference = Pipe O.D. × 1.57

The transducer spacing is the same as found in the Transducer Positioning section.

Mark opposite corners of the paper on the pipe. Apply transducers to these two marks.

26

LESS THAN ¼” (6 mm)

7) Place the downstream transducer on the
pipe at the calculated transducer spacing.
See Figure 2.13. Using  rm hand pressure,
slowly move the transducer both towards
and away from the upstream transducer
while observing signal strength. Clamp
the transducer at the position where the
highest signal strength is observed. Signal
strength of between 5 and 98 is accept­able. The factory default signal strength
setting is 5, however there are many
application speci c conditions that may
prevent the signal strength from attaining
this level.

A minimum signal strength of 5 is accept­able as long as this signal level is main­tained under all  ow conditions.
On certain pipes, a slight twist to the
transducer may cause signal strength to
rise to acceptable levels.

FIGURE 2.11  PAPER TEMPLATE ALIGNMENT

5) For FDT-47, FDT-48, and FDT-47-HT
transducers, place a single bead of
couplent, approximately ½ inch (12
mm) thick, on the  at face of the
transducer. See Figure 2.4. Generally,
a silicone-based grease is used as an
acoustic couplent, but any good quality
grease-like substance that is rated to
not “ ow” at the temperature that the
pipe may operate at will be acceptable.

6) Place the upstream transducer in posi­tion and secure with a stainless steel
strap or other fastening device. Straps
should be placed in the arched groove
on the end of the transducer. A screw
is provided to help hold the trans­ducer onto the strap. Verify that the
transducer is true to the pipe, adjust
as necessary. Tighten transducer strap
securely. Larger pipes may require
more than one strap to reach the
circumference of the pipe.

Edge of

Paper

Line Marking

Circumference

Fold

Pipe Circumference

Transducer

Spacing

Crease

(Center of Pipe)

FIGURE 2.12  BISECTING THE PIPE CIRCUMFERENCE

27

8) Certain pipe and liquid characteristics may
cause signal strength to rise to greater
than 98. The problem with operating this
meter with very high signal strength is that
the signals may saturate the input ampli­ ers and cause erratic readings. Strate­gies for lowering signal strength would
be changing the transducer mounting
method to the next longest transmis­sion path. For example, if there is exces­sive signal strength and the transducers
are mounted in a Z-Mount, try changing
to V-Mount or W-Mount. Finally you can
also move one transducer slightly o line
with the other transducer to lower signal
strength.

9) Secure the transducer with a stainless steel
strap or other fastener.

MOUNTING TRACK INSTALLATION

TOP VIEW

OF PIPE

FIGURE 2.13  ZMOUNT TRANSDUCER PLACEMENT

1) A convenient transducer mounting track can be used for pipes that have outside diameters
between 2 and 10 inches (50 and 250 mm). If the pipe is outside of that range, select a V-Mount
or Z-Mount mounting method.

2) Install the single mounting rail on the side of the pipe with the stainless steel bands provided. Do
not mount it on the top or bottom of the pipe. Orientation on vertical pipe is not critical. Ensure
that the track is parallel to the pipe and that all four mounting feet are touching the pipe.

3) Slide the two transducer clamp brackets towards the center mark on the mounting rail.

4) Place a single bead of couplent, approximately ½ inch (12 mm) thick, on the  at face of the trans­ducer. See Figure 2.4.

5) Place the  rst transducer in between the mounting rails near the zero point on the scale. Slide the
clamp over the transducer. Adjust the clamp/transducer such that the notch in the clamp aligns
with zero on the scale. See Figure 2.14.

6) Secure with the thumb screw. Ensure that the screw rests in the counter bore on the top of the
transducer. (Excessive pressure is
not required. Apply just enough
pressure so that the couplent  lls
the gap between the pipe and
transducer.)

7) Place the second transducer in
between the mounting rails near
the dimension derived in the
transducer spacing section. Read
the dimension on the mounting
rail scale. Slide the transducer
clamp over the transducer and
secure with the thumb screw.

Top View

of Pipe

28

FIGURE 2.14  MOUNTING TRACK INSTALLATION

PART 3  INPUTS/OUTPUTS

GENERAL

The  ow metering system is available in two general con gurations. There is the standard  ow meter
model that is equipped with a 4-20 mA output, two open collector outputs, a rate frequency output, and
RS485 communications using the

The energy version of the  ow metering family has inputs for two 1,000 Ohm RTD sensors in place of
the rate frequency and alarm outputs. This version allows the measurement of pipe input and output
temperatures so energy usage calculations can be performed.

420 mA OUTPUT

The 4-20 mA output interfaces with most recording and logging systems by transmitting an analog
current signal that is proportional to system  ow rate. The 4-20 mA output is internally powered (current
sourcing) and can span negative to positive  ow/energy rates.

For AC powered units, the 4-20 mA output is driven from a +15 VDC source located within the meter.
The source is isolated from earth ground connections within the  ow meter. The AC powered model
can accommodate loop loads up to 400 Ohms. DC powered meters utilize the DC power supply voltage
to drive the current loop. The current loop is not isolated from DC ground or power. Figure 3.1 shows
graphically the allowable loads for various input voltages. The combination of input voltage and loop
load must stay within the shaded area of Figure 3.1.

Modbus RTU command set.

Supply Voltage - 7 VDC

0.02

1100

1000

900
800
700
600
500
400

= Maximum Loop Resistance

Operate in the

Loop Load (Ohms)

300
200
100

10 12 14 16 18 20 22 24 26 28

Shaded Regions

Supply Voltage (VDC)

FIGURE 3.1  ALLOWABLE LOOP RESISTANCE DC POWERED UNITS

29

90-265 VAC
AC Neutral

Signal Ground

Signal Gnd.
Control 1

Loop

Resistance

Control 2
Frequency Out
4-20 mA Out
Reset Total

7 VDC

Drop

Meter Power

FIGURE 3.2  420 MA OUTPUT

The 4-20 mA output signal is available between the 4-20 mA Out and Signal Gnd terminals as shown in
Figure 3.2.

CONTROL OUTPUTS FLOW ONLY VERSION

Two independent open collector transistor outputs are included with the
 ow only model. Each output can be con gured for one of the following
four functions:

O

1234

N

Rate Alarm
Signal Strength Alarm
Totalizing/Totalizing Pulse
Errors
None

FIGURE 3.3  SWITCH SETTINGS

Both control outputs are rated for a maximum of 100 mA and 10 to 28 VDC. A pull-up resistor can be
added externally or an internal 10K Ohm pull-up resistor can be selected using DIP switches on the
power supply board.

Switch S1 S2 S3 S4

On

O

Control 1 Pull-Up
Resistor IN circuit

Control 1 Pull-Up

Resistor OUT of circuit

Control 2 Pull-Up
Resistor IN circuit

Control 2 Pull-Up

Resistor OUT of circuit

Frequency output Pull-Up

Resistor IN circuit

Frequency Output Pull-Up

Resistor OUT of circuit

Square Wave

Output

Simulated Turbine

Output

TABLE 3.1  DIP SWITCH FUNCTIONS

NOTE: All control outputs are disabled when USB cable is connected.

30