Sierra InnovaSonic 205i User manual

InnovaSonic®205i
General Purpose
Ultrasonic Liquid Flow Meter
Instruction Manual
Version IM-205i, Rev. O, April 2017

Sierra Instruction Manual InnovaSonic®205i
IM-205i Page 1 of 78
GLOBAL SUPPORT LOCATIONS: WE ARE HERE TO HELP!
CORPORATE HEADQUARTERS
5 Harris Court, Building L Monterey, CA 93940
Phone [phone] [phone] Fax [phone]
www.sierrainstruments.com
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Phone [phone] Fax [phone]
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25 Hangdu Road Hangtou Town
Pu Dong New District, Shanghai, P.R. China
Postal Code 201316
Phone: + 8621 5879 8521 Fax: [phone]
© COPYRIGHT SIERRA INSTRUMENTS 2016
No part of this publication may be copied or distributed, transmitted, transcribed, stored in a retrieval system, or translated
into any human or computer language, in any form or by any means, electronic, mechanical, manual, or otherwise, or
disclosed to third parties without the express written permission of Sierra Instruments. The information contained in this
manual is subject to change without notice.
TRADEMARKS
InnovaSonic® is a Registered Trademark of Sierra Instruments, Inc. Other product and company names listed in this
manual are trademarks or trade names of their respective manufacturers.

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Important Customer Notice
Thank you for choosing the InnovaSonic®Model 205i Dedicated & Energy BTU Transit-Time Ultrasonic Flow Meter with SLSI
CMOS and low-voltage wide-pulse sending technology. This manual contains important information about your meter. Before
installing and operating this flow meter, please read this manual carefully and follow its instructions.
✓Sierra has verified the conformity between the contents in this manual and the hardware and software described.
However, errors may still exist. We regularly review the materials covered in this manual and correct errors with revisions.
Any suggestions for improvement will be appreciated.
✓Go to www.sierrainstruments.com/products/downloads.html for a most current electronic version of this manual.
✓We reserve the right to change the content of this manual without prior notification.
✓If you have any questions or problems regarding this manual, please contact Sierra’s Customer Service
Customer Service Department:
Toll Free: 800-866-0200 Phone: [phone] Fax: [phone]
Email: [email protected]
WARNINGS IN THIS MANUAL
Warning, attention, and note statements are used throughout this book to draw your attention to important
information.
WARNING
“Warning” statement appears with information that is important to protect people and
equipment from damage. Pay very close attention to all warnings that apply to your
application. Failure to comply with these instructions may damage the meter and
personal injury.
ATTENTION
“Attention” statements in this manual indicate that failure to comply with stated instructions
may result in damage to the meter or faulty operation of the flow meter.
NOTE
“Note” indicates that ignoring the relevant requirements or precautions may result in flow
meter damage or malfunction.

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Product Components
Inspection should be made before installing the InnovaSonic 205i. Check to see if the spare parts are in
accordance with the packing list. Make sure that there is no damage to the enclosure due to a loose screw or loose
wire, or other damage that may have occurred during transportation. Any questions, please contact your
representative as soon as possible.

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Content
1. Transmitter Installation and Connect........................................................7
1.1. Inspection Prior to Transmitter Installation.................................................................................................. 7
1.2. Power Supply Connecting........................................................................................................................... 7
1.2.1 Direct Mount Method.......................................................................................................................................7
1.2.2 Connecting the Wiring ....................................................................................................................................8
1.3. Powering On ............................................................................................................................................... 8
1.4. Keypad Functions....................................................................................................................................... 9
1.4.1 Quick Access Key Operation....................................................................................................................... 9
1.4.2 Dual-Function Keypad Operation .............................................................................................................. 10
1.5. Keypad Operation ......................................................................................................................................11
1.6. Flow Meter Window Descriptions .............................................................................................................. 10
2. Pipe Parameter Entry Shortcuts ..............................................................11
3. Measurement Site Selection ......................................................................13
4. Transducer Installation .............................................................................14
4.1. Installing the Transducers......................................................................................................................... 14
4.1.1 Transducer Spacing ......................................................................................................................................14
4.1.2 Transducer Mounting Methods......................................................................................................................14
4.1.3 V Method.......................................................................................................................................................14
4.1.4 Z Method.......................................................................................................................................................15
4.1.5 N Method (not commonly used).....................................................................................................................15
4.2. Transducer Mounting Inspection............................................................................................................... 15
4.2.1 Signal Strength .............................................................................................................................................15
4.2.2 Signal Quality (Q value).................................................................................................................................16
4.2.3 Total Time and Delta Time .............................................................................................................................16
4.2.4 Transit Time Ratio .........................................................................................................................................16
5. Operating Instructions ..............................................................................18
5.1. System Normal Identification .................................................................................................................... 18
5.2. Zero Set Calibration .................................................................................................................................. 18
5.3. Scale Factor.............................................................................................................................................. 18
5.4. System Lock (Unlock) ............................................................................................................................... 19
5.5. 4~20mA Current Loop Verification............................................................................................................. 19
5.6. Frequency Output ..................................................................................................................................... 19
5.7. Totalizer Pulse Output............................................................................................................................... 20
5.8. Alarm Programming.................................................................................................................................. 20
5.9. Batch Controller........................................................................................................................................ 21
5.10. Analog Output Calibration......................................................................................................................... 21

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5.11. Use of the Memory Card............................................................................................................................ 22
5.11.1 Specifications...........................................................................................................................................22
5.11.2 Installing or Removing the SD Card While the Meter is Powered On..........................................................23
5.11.3 Reading the SD Data Externally.................................................................................................................23
5.11.4 Reading the SD Data Internally with the Instrument Powered On...............................................................23
5.11.5 File Converter Tool....................................................................................................................................25
5.12. Recover the Factory Default...................................................................................................................... 25
5.13. ESN .......................................................................................................................................................... 26
6. Windows Display Explanations ................................................................27
6.1. Windows Display Codes ........................................................................................................................... 27
6.2. Display Explanation .................................................................................................................................. 28
7. Error Diagnosis..........................................................................................47
7.1. Table 1. Self-Diagnosis and Error Solutions (upon power on).................................................................... 47
7.2. Table 2. Error Codes and Solutions (during operation).............................................................................. 48
7.3. Frequently Asked Questions and Answers................................................................................................ 49
8. Product Overview ......................................................................................50
8.1. Introduction .............................................................................................................................................. 50
8.2. Features of InnovaSonic 205i .................................................................................................................... 50
8.3. Theory of Operation.................................................................................................................................. 50
8.4. Applications.............................................................................................................................................. 52
8.5. Specifications ........................................................................................................................................... 53
9. Appendix 1 - Flow Application Data........................................................56
9.1. Sound Velocity and Viscosity for Fluids Commonly Used ......................................................................... 56
9.2. Sound Velocity for Various Materials Commonly Used .............................................................................. 56
9.3. Sound Velocity in Water (1 atm) at Different Temperatures ........................................................................ 57
10. Appendix 2 - Wetted Transducer..............................................................59
10.1. Overview................................................................................................................................................... 59
10.2. Measurement Point Selection.................................................................................................................... 59
10.3. Determining Transducer Spacing & Transducer Installation ...................................................................... 60
10.4. Transducer Mounting Methods.................................................................................................................. 61
10.4.1 Z Mounting Method...................................................................................................................................61
10.4.2 V Mounting Method...................................................................................................................................61
11. Appendix 3 - Serial Interface / Network Use...........................................62
11.1. Overview................................................................................................................................................... 62
11.2. RS-232 / RS-485 Pin Definitions................................................................................................................. 62
11.3. Connection of RS-232 or RS-485 ............................................................................................................... 63
11.4. Setting Up the 205i to Use Modbus RTU..................................................................................................... 63

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11.5. Modbus-RTU Protocol................................................................................................................................ 64
12. Appendix 4 - Warranty Policy ..................................................................68
12.1 Limited Warranty Policy- Register Online.................................................................................................... 68

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1. Transmitter Installation and Connect
1.1. Inspection Prior to Transmitter Installation
You will find a “Position Drawing”
in the packing. Please use it as a
template in the place that you are
going to install the flow meter.
Then drill 4 installation holes at
the screw positions shown on the
drawing with a 5.5mm drill.
Take out the enclosed screws and
plastic bushings. Insert the plastic
bushings into the drill holes. Then
open the two aluminum pieces on
the two sides of the top cover. Put
the flow meter into position and
screw it in.
Attention
When installing please ensure the front cover is secure and will not fall open.
1.2. Power Supply Connecting
1.2.1 Direct Mount Method
Customers should pay special attention to specify the desired power supply when placing an order. Factory
standard power supply is 90~245 VAC, 15 Watts.
Observe the following precautions for installation procedures outlined in this chapter:
Ensure that power connections are made in accordance with the indications shown on the connection terminals.
Transmitters can be powered with 90~245VAC 15 watts or 10-36VDC @500mA.
120 mm
182 mm
7.17lnch
4.72lnch
Position drawing
Instrutions:
1. Place this template on the wall and drill 4 holes of 8mm
2. Insert a plastic bushing into each of the 4 holes.
3. Screw 4 pcs ST5.5X50mm self tapping screws through the
4. Tighten the screws to secure to the enclosure on the wall.
transmitter enclosure base and attach it to the wall.
diameter & 50mm deep.

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1.2.2 Connecting the Wiring
Once the electronics enclosure has been installed, the flow meter wiring can be connected.
Power board wiring ports, from left to right, are as follows:
Connect to AC power (90-245V), DC power (10-36V), Relay Output, OCT Output, Analog Input, Transducer
wiring, 4-20mA Output, RS-232 Output, and RS-485 Output. (Be aware that “A” and “B” may be reversed by
some interface manufactures; you may need to switch them)
For double-shielded transducer cable: "-" on the black wire, "+" on the red wire, and "shield" on the shield.
Figure 1. Wire Connection
Warning
Wire with power off.
Use either AC or DC power supply. Do not connect them both at the same time.
1.3. Powering On
As soon as the 205i is switched on, the self-diagnosis program will start to run. If any error is detected, an error
code will display on the screen (Refer to Error Diagnoses). After that, the system will run automatically according
to the last input parameters.
If the installation is accomplished when the system is switched on, gain adjustment can be monitored in Window
M01. After S1, S2, S3, and S4 are displayed on the upper left corner of the screen, the system will activate the
normal measurement condition automatically. It is indicated by code “*R” on the upper right corner of the screen.
The system will default to the last window settings and automatically display them at next power on.
Down-Stream
Red wire Black wire
Blue BushingRed Bushing
Up-Stream
Flow
AC Power
L N E
AC 90～245V
DC+ DC-
DC10-36V
RL1 RL2
RELAY
OCT+ OCT-
OCT OUT
AI1 AI2 GND
ANALOG IN
E UP+ UP- E DN+ DN-
TRANSDUCER
I+ I- TX RX GND A B
4-20mA RS232 RS485
Black wire
Shield wire
Red wire
Shield wire

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1.4. Keypad Functions
The InnovaSonic 205i keypad offers 12 dual-function keys for operation of the menu system plus six quick-setup
keys. For quick setup of your InnovaSonic, simply press any of the keys across the top to get the desired menu
instantly. See image of keypad below.
Follow these guidelines when using the InnovaSonic 205i menu system:
▪Keys to are the menu codes to input
information required for the flow measurement exercise.
▪Use the key to delete or move back to the previous
menu.
▪ To toggle up and down in a menu, use the up or down
arrow keys.
▪After all data is selected, press the Enter key to
confirm your choices.
▪The Menu key is used to select a menu using two-digit
numbers for each menu. For example, to enter pipe outside
diameter, press to enter into the window (“MENU11”is the address code of the
outer pipe diameter).
1.4.1 Quick Access Key Operation
Rate Key
Press this key to display Flow Rate. The function is
the same with Window M02.
Velocity Key
Press this key to display Velocity. The function is the
same with Window M01.
Signal Key
Press this key to display Signal Strength and Signal
Quality. The function is the same with Window M90.
Totalizer Key
Press this key to display Net Totalizer. The function is
the same with Window M00.
Toms/Tos Key
Press this key to display Transit Time Ratio. The
function is the same with Window M91.
Flow 0.1129m3/ h * R
POS 0x 1m3
Flow 0.1129m3/ h * R
Vel 1.0415m/s
St r ength + Quali ty [90
UP:00.0 DN:00.0 Q=00
Flow 0.1154m3/ h *R
NET 0x 1m3
TOM/TOS* 100 [91
0.0000%
Figure 2. 205i Keypad

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Diag. Key
Press this key to display System Error Code. The
function is the same with Window M08.
1.4.2 Dual-Function Keypad Operation
Pipe Diameter/1 Key
Press this key to enter Pipe Outer Diameter in
Window M11.
Pipe Thickness/2 Key
Press this key to enter Pipe Wall Thickness in
Window M12.
Pipe Material/3 Key
Press this key to enter Pipe Material in Window M14.
Fluid Type/4 Key
Press this key to enter Fluid Type in Window M20.
Transducer Mount/5 Key
Press this key to enter Transducer Mounting in
Window M24.
Start/Stop/6 Key
Press this key to start and stop Manual Totalizer in
turn.
Hold/7 Key
Press this key to display the Display / Hold Totalizer
in turn.
Fluid Velocity/8 Key
Press this key to display Dynamic / Normal Flow
Rate and Velocity in turn.
Sound Velocity/9 Key
Press this key to enter Fluid Sound Velocity in
Window M92.
Date/Time/. Key
Press this key to display Date and Time. The function
*R---------
Sy s tem Nor mal
Pi pe Out er Di amet er
50 mm
Pi pe Wall Thi c k nes s
4mm
Pi pe Mater i al [14
0. Car bon St eel
Flui d Ty pe [20
0. Wat er
Tr ans duc er Mounti ng
0. V
60 s ec
ON 10.123 m3
Flow 0.1129 m3/h* R
POS 0X1m3
Flow 0.1129 m3/h Dy n
Vel 1.0415 m/s
Flui d Sound Veloc i ty
1443.4 m/s
YY-MM- DD HH:MM:SS
03-04-04 10:05:04

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is the same with Window M60.
Calibrate/0 Key
Press key to start Manual Totalizer, and then
press key to end Manual Totalizer.
Zero/< Key
Press this key to input code 1234 to set zero.
1.5. Keypad Operation
With all of the parameters entered, the instrument setup and measurement displays are subdivided or consolidated
into more than 100 independent windows. The operator can input parameters, modify settings, or display
measurement results by “visiting” a specific window. These windows are arranged by 2-digit serial numbers
(including “+” sign) from 00~99, then to +0, +1, etc. Each window serial number, or so-called window ID code,
has a defined meaning. For example, Window M11 indicates the parameter input for pipe outside diameter, while
Window M25 indicates the mounting spacing between the transducers, etc. (Refer to Windows Display
Explanations).
The keypad shortcut to visit a specific window is to press the key at any time, then input the 2-digit window
ID code. For example, to input or check the pipe outside diameter, just press for window ID code
11.
Another method to visit a particular window is to press and to scroll the screen. For example, if
the current window ID code is 66, press the key to enter Window M65, press the key again to enter
Window M64; then, press the key to go back to Window M65, and press the key again to enter
Window M66.
Example 1: To enter a pipe outside diameter of
219.234, the procedure is as follows:
Press to enter Window M11 (the
numerical value displayed currently is a previous
value). Now press the key. The symbol “>”
and the flashing cursor are displayed at the left end of
the second line on the Screen. Then the new value can
be entered…
Example 2: If the pipe material is “Stainless Steel”,
press to enter Window M14 first. Then
press the key to modify the options. Now, select
the “1. Stainless Steel” option by pressing the
and keys, and then press the key to confirm
the selection. It’s possible to press the key to
Manual Cali br ate
Pr es s Ent When Ready
Set Zer o
Pleas e Enter PW
Pi pe Outer Di ameter
>_
Pi pe Mater i al [14
>1. St ai nles s St eel

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change the selection and wait until “1. Stainless Steel”
is displayed on the second line of the screen. Then
press the key.
ATTENTION
Press the key first if the operator wants to modify condition. If the modify is still not
possible even after pressing the key, it means that the system is locked by a password.
To “Unlock” it, select “Unlock” in Window M47 and enter the original password. The keypad will
not respond if the keypad is locked.
1.6. Flow Meter Window Descriptions
The InnovaSonic 205i has the unique feature of windows processing for all operations.
The windows are assigned as follows:
00~09 Flow Totalizer Display: display flow rate, positive total, negative total, net total, velocity, date & time,
analog inputs for present flow, present operation and flow results today, etc.
10~29 Initial Parameter Setup: enter pipe outside diameter, pipe wall thickness, fluid type, transducer type,
transducer mounting and spacing, etc.
30~38 Flow Units Options: select the flow unit, totalizer unit, measurement unit, turn totalizer on/off, reset
totalizer, etc.
40~49 Setup Options: scaling factor, network IDN (Window M46), system lock (Window M47), etc.
50~89 Input and Output Setup: relay output setup, 4-20mA outputs, flow batch controller, LCD backlit option,
date and time, low/high output frequency, alarm output, date totalizer, etc.
90~95 Diagnosis: signal strength and signal quality (Window M90), TOM/TOS*100 (Window M91), flow
sound velocity (Window M92), total time and delta time (Window M93), Reynolds number and factor
(Window M94), data interval (Window M95), etc.
+0~+5 Appendix: power on/off, total working hours, on/off times, and a single-accuracy function calculator.
ATTENTION
The other windows are for hardware adjustment by the manufacturer.

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2. Pipe Parameter Entry Shortcuts
For example, measuring the diameter of DN200 when the measuring medium is water, the material is carbon steel,
and there’s no liner, can be operated as follows:
Note: Set menu 30 to English for ANSI pipe sizes.
Step 1. Pipe outside diameter
Press to enter Window M11 and
enter the pipe outside diameter, and then press
the key.
Step 2. Pipe wall thickness
Press to enter Window M12
and enter the pipe wall thickness, and then
press the key.
WARNING
The wall thickness needs to be at least 0.001mm for use with insertion sensors.
Step 3. Pipe material
Press to enter Window M14,
press the key, press the or
keys to select pipe material, and press the
key.
Step 4. Liner material parameters
(Including thickness and sound velocity, if
needed)
Press to enter Window M16,
press the key, press the or
keys to select liner material, and then press the
key.
Step 5. Fluid type
Press to enter Window M20,
press the key, press the or
keys to select fluid type, and then press the
key.
Step 6. Transducer type
(The transmitter is available for various
transducer types)
Press to enter Window
M23, press the key, press the or
keys to select transducer type, and then
press the key.
Pi pe Outer Di ameter
200 mm
Pi pe Wall Thi c k nes s
6mm
Pi pe Mater i al [14
0. Car bon St eel
Li ner Mat er i al [16
0. None, No Li ner
Flui d Ty pe [20
0. Wat er
Tr ans duc er Type [23
0. Standar d

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NOTE
The S, W, and WH type sensors are all standard type.
Step 7. Transducer mounting methods
Press to enter Window M24,
press the key, press the or
keys to select transducer mounting method,
and then press the key.
Step 8. Adjust transducer spacing
Press to enter Window M25
and accurately install the transducer according
to the displayed transducer mounting spacing
and the selected mounting method. (Refer to
Installing the Transducers in this chapter)
Step 9. Display measurement result
Press to enter Window M01 to
display measurement result.
Tr ans duc er Mounti ng
0. V
Tr ans duc er Spaci ng
159.86 mm
Flow 0.1129m3/ h * R
Vel 1.0415m/s

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3. Measurement Site Selection
When selecting a measurement site, it is important to select an area where the fluid flow profile is fully developed
to guarantee a highly accurate measurement. Use the following guidelines to select a proper installation site:
Choose a section of pipe that is always full of liquid, such as a vertical pipe with flow in the upward direction or a
full horizontal pipe. Ensure enough straight pipe length at least equal to the figure shown below for the upstream
and downstream transducers installation.
Figure 3. Measurement Site Selection
Ensure that the pipe surface temperature at the measuring point is within the transducer temperature limits.
Consider the inside condition of the pipe carefully. If possible, select a section of pipe where the inside is free of
excessive corrosion or scaling.
Pump
Valve
Reduce
Diffuser
Tee
90obend
Straight length of
downstream piping
Straight length of upstream
piping
Name
Detector
10D min
0.5D min
L≥5D
L ≥5D
L≥10D
Flow controlled downstream
10D min
L ≥10D
L ≥5D
L ≥10D
10D min
L ≥50D
L ≥30D
D
5D min
L≥10D
L≥30D
Flow controlled upstream
L≥50D
P
Check valve
Stop valve

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4. Transducer Installation
4.1. Installing the Transducers
Before installing the transducers, clean the pipe surface where the transducers are to be mounted. Remove any rust,
scale or loose paint and make a smooth surface. Choose a section of sound conducting pipe for installing the
transducers. Apply a wide band of sonic coupling compound down the center of the face of each transducer as
well as on the pipe surface, and then attach the transducers to the pipe with the straps provided and tighten them
securely.
NOTE
The two transducers should be mounted at the pipe’s centerline on horizontal pipes.
Make sure that the transducer mounting direction is parallel with the flow.
During the installation, there should be no air bubbles or particles between the transducer and the pipe wall. On
horizontal pipes, the transducers should be mounted in the 3 o’clock and 9 o’clock positions of the pipe section in
order to avoid any air bubbles inside the top portion of the pipe. (Refer to Transducer Mounting). If the
transducers cannot be mounted horizontally symmetrically due to limitation of the local installation conditions, it
may be necessary to mount the transducers at a location where there is a guarantee full pipe condition (the pipe is
always full of liquid).
4.1.1 Transducer Spacing
After entering the required parameters, the spacing between the ENDS of the two transducers is considered as the
standard transducer spacing (Refer to Top View on transducer mounting methods). Check the data displayed in
Window M25 and space the transducers accordingly.
4.1.2 Transducer Mounting Methods
Four transducer mounting methods are available. They are respectively: V method, Z method and N method. The
V method is primarily used on small diameter pipes (DN100~400mm, 4”~16”). The Z method is used in
applications where the V method cannot work due to poor signal or no signal detected. In addition, the Z method
generally works better on larger diameter pipes (over DN300mm, 12”) or cast iron pipes. The N method is an
uncommonly used method. It is used on smaller diameter pipes (below DN50mm, 2”).
4.1.3 V Method
The V method is considered as the standard method. It usually gives a more accurate reading and is used on pipe
diameters ranging from 25mm to 400mm (1~16”) approximately. Also, it is convenient to use, but still requires
proper installation of the transducer, contact on the pipe at the pipe’s centerline and equal spacing on either side of
the centerline.
Figure 4. V Method Transducer Mounting
Downstream Transducer
Upstream Transducer
Flow
Transducer Space
Flow
Side View Top ViewSection
Pipe Strap
Transducer

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4.1.4 Z Method
The signal transmitted in a Z method installation has less attenuation than a signal transmitted with the V method.
This is because the Z method utilizes a directly transmitted (rather than reflected) signal which transverses the
liquid only once. The Z method is able to measure on pipe diameters ranging from approximately 100mm to
3000mm (4”~120”). We recommend the Z method for pipe diameters over 300mm (12”).
Figure 5. Z Method Transducer Mounting
4.1.5 N Method (not commonly used)
With the N method, the sound waves traverse the fluid three times and bounce twice times off the pipe walls. It is
suitable for small pipe diameter measurement. The measurement accuracy can be improved by extending the
transit distance with the N method (uncommonly used).
Figure 6. N Method Transducer Mounting
4.2. Transducer Mounting Inspection
Check to see if the transducer is installed properly and if there is an accurate and strong enough ultrasonic signal
to ensure proper operation and high reliability of the transducer. It can be confirmed by checking the detected
signal strength, total transit time, delta time as well as transit time ratio.
The “mounting” condition directly influences the flow value accuracy and system long-time running reliability. In
most instances, only apply a wide bead of sonic coupling compound lengthwise on the face of the transducer and
stick it to the outside pipe wall to get good measurement results. However, the following inspections still need to
be carried out in order to ensure the high reliability of the measurement and long-term operation of the instrument.
4.2.1 Signal Strength
Signal strength (displayed in Window M90) indicates a detected strength of the signal both from upstream and
downstream directions. The relevant signal strength is indicated by numbers from 00.0~99.9. 00.0 represents no
signal detected while 99.9 represents maximum signal strength.
Normally, the stronger the signal strength detected, the longer the operation of the instrument reliably, as well as
the more stable the measurement value obtained.
Downstream Transducer
Upstream Transducer
Flow
Transducer Spacing
Flow
Side View Top ViewSection
Pipe Strap
Transducer
Downstream Transducer
Upstream Transducer
Flow
Transducer Spacing
Flow
Side View Top ViewSection
Pipe Strap
Transducer

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Adjust the transducer to the best position and check to ensure that enough sonic coupling compound is applied
adequately during installation in order to obtain the maximum signal strength.
System normally requires signal strength over 60.0, which is detected from both upstream and downstream
directions. If the signal strength detected is too low, the transducer installation position and the transducer
mounting spacing should be re-adjusted and the pipe should be re-inspected. If necessary, change the mounting to
the Z method.
4.2.2 Signal Quality (Q value)
Q value is short for Signal Quality (displayed in Window M90). It indicates the level of the signal detected. Q
value is indicated by numbers from 00~99. 00 represents the minimum signal detected while 99 represents the
maximum.
Normally, the transducer position should be adjusted repeatedly and coupling compound application should be
checked frequently until the signal quality detected is as strong as possible.
4.2.3 Total Time and Delta Time
“Total Time and Delta Time”, which displays in Window M93, indicates the condition of the installation. The
measurement calculations in the flow meter are based upon these two parameters. Therefore, when “Delta Time”
fluctuates widely, the flow and velocities fluctuate accordingly. This means that the signal quality detected is too
poor. It may be the result of poor pipe installation conditions, inadequate transducer installation, or incorrect
parameter input.
Generally, “Delta Time” fluctuation should be less than ±20%. Only when the pipe diameter is too small or
velocity is too low can the fluctuation be wider.
4.2.4 Transit Time Ratio
Transit Time Ratio indicates if the transducer mounting spacing is accurate. The normal transit time ratio should
be 100±3 if the installation is correct. Check it in Window M91.
ATTENTION
If the transit time ratio is over 100±3, it is necessary to check:
(1) If the parameters (pipe outside diameter, wall thickness, pipe material, liner, etc.) have
been entered correctly.
(2) If the transducer mounting spacing is accordance with the display in Window M25.
(3) If the transducer is mounted at the pipe’s centerline.
(4) If the scale is too thick or the pipe mounting is distorted in shape, etc.

Sierra Instruction Manual InnovaSonic®205i
IM-205i Page 17 of 78
WARNINGS
(1) Pipe parameters entered must be accurate; otherwise the flow meter will not
work properly.
(2) During the installation, apply enough coupling compounds in order to stick the
transducer onto the pipe wall. While checking the signal strength and Q value,
move the transducer slowly around the mounting site until the strongest signal
and maximum Q value can be obtained. Make sure that the larger the pipe
diameter, the more the transducer should be moved.
(3) Check to be sure the mounting spacing is accordance with the display in Window
M25 and the transducer is mounted at the pipe’s centerline.
(4) Pay special attention to those pipes that are formed by steel rolls (pipe with
seams), since such pipe is always irregular. If the signal strength is always
displayed as 0.00, that means there is no signal detected. Thus, it is necessary
to check that the parameters (including all the pipe parameters) have been
entered accurately. Check to be sure the transducer mounting method has been
selected properly, the pipe is not worn-out, and the liner is not too thick. Make
sure there is indeed fluid in the pipe or the transducer is not very close to a valve
or elbow, and there are not too many air bubbles in the fluid, etc. With the
exception of these reasons, if there is still no signal detected, the measurement
site has to be changed.
(5) Make sure that the flow meter is able to run properly with high reliability. The
stronger the signal strength displayed, the higher the Q value reached, the longer
the flow meter runs accurately, the higher the reliability of the flow rates
displayed. If there is interference from ambient electromagnetic waves or the
signal detected is too poor, the flow value displayed is not reliable; consequently,
the capability for reliable operation is reduced.
(6) The transducer spacing in MENU 25 assumes perfect quality conditions. The
flow meter was calibrated on a “perfect condition” flow calibration loop. It is
necessary to check and perhaps adjust the transducer spacing in the real life
application to ensure that the MENU 90 and MENU 91 diagnostic readings are
within limits. MENU 90 should indicate Signal Strength UP and DOWN > 60
and the Quality value “Q” > 50. MENU 91, the Transit Time Ratio (TOM/TOS)
must be 100 +/-3%.