Dakota Ultrasonics DFX-6 Operating Manual
DFX-625
User’s Guide
DFX-625 User’s Guide ~ Contents
Copyright © 2008 Dakota Ultrasonics
All rights reserved. No part of this publication may be reproduced, stored in a retrieval
system or transmitted in any form or by any means, electronic, mechanical, photocopying,
recording or otherwise, without the prior written permission of Dakota Ultrasonics.
Dakota Ultrasonics
1500 Green Hills Road, #107
Scotts Valley, CA 95066 USA
Phone: 831 431-9722
Fax: 831 431-9723
email: info@dakotainst.com
Web: www.dakotaultrasonics.com
DFX-625 User’s Guide ~ Contents
Contents
Contents.........................................................................................................................................i
1 How to Use This User’s Guide................................................................................................1
1.1 Typographical Conventions ...........................................................................................1
2 Disclaimers and Notices .........................................................................................................2
2.1 Specific Warnings..........................................................................................................2
2.2 General Warnings..........................................................................................................2
2.3 Operator Training ..........................................................................................................2
2.4 Testing Limitations.........................................................................................................2
2.5 Critical Operating Factors..............................................................................................2
2.5.1 Calibration of the Sound Velocity...............................................................................3
2.5.2 Transducer (Probe) Zero Procedure..........................................................................4
2.5.3 Flaw Detection Calibration.........................................................................................4
2.5.4 Effects of Temperature on Calibration.......................................................................4
2.5.5 Transducer Condition ................................................................................................4
2.5.6 Use of Couplant.........................................................................................................4
2.6 Disclaimer of Liability.....................................................................................................5
2.7 Electromagnetic Compatibility .......................................................................................5
3 Quick Start ..............................................................................................................................6
3.1 Front Panel Controls & End Cap Connections ..............................................................6
3.2 Flaw Detection...............................................................................................................9
3.3 Thickness Gauging......................................................................................................10
3.4 DFX-625 Memory ........................................................................................................11
3.4.1 Reset to factory defaults:.........................................................................................11
3.4.2 Clearing the Memory ...............................................................................................11
4 Detailed Menu Description....................................................................................................12
4.1 Menu Tree ...................................................................................................................12
4.2 Main Menu...................................................................................................................13
4.2.1 Main Menu Selection ...............................................................................................13
4.3 CAL Menu....................................................................................................................14
4.3.1 Calibration Menu .....................................................................................................14
4.3.2 Amplifier Menu.........................................................................................................14
4.3.3 GATE1 & GATE2 Menus .........................................................................................15
4.3.4 A-CAL Menu ............................................................................................................15
4.4 MEAS Menu ................................................................................................................17
4.4.1 Measurement Menu.................................................................................................17
4.4.2 CSC (Curved Surface Correction) ...........................................................................19
4.4.3 PROBE Menu ..........................................................................................................19
4.4.4 Distance Amplitude Correction (DAC) Menu ...........................................................20
4.4.5 DGS/AVG ................................................................................................................21
4.4.6 TCG Time Corrected Gain Menu.............................................................................22
4.4.7 AWS Menu ..............................................................................................................23
4.4.8 API Menu.................................................................................................................24
4.5 UTIL Menu...................................................................................................................25
4.5.1 UTIL Menu...............................................................................................................25
4.5.2 VIDEO Menu ...........................................................................................................25
4.5.3 MISC Menu..............................................................................................................25
4.5.4 AGC (Automatic Gain Control) ................................................................................26
4.5.5 PRINT Menu............................................................................................................27
4.5.6 P_O/P Proportional Output Control Menu ...............................................................27
4.5.7 CLOCK Menu ..........................................................................................................28
4.6 MEMORY Menu ..........................................................................................................29
Page i
DFX-625 User’s Guide ~ Contents
4.6.1 PANEL Memory Menu............................................................................................. 29
4.6.2 A-LOG Memory Menu ............................................................................................. 30
4.6.3 REF Menu ............................................................................................................... 31
4.6.4 T-LOG Menu Numeric Mode ................................................................................... 31
4.6.5 T-LOG Menu Sequential Mode ............................................................................... 32
4.6.6 T-FN Menu .............................................................................................................. 32
4.7 Storage & Recall of Calibration Setups....................................................................... 33
4.7.1 To store a panel set:................................................................................................ 33
4.7.2 To recall a panel set: ............................................................................................... 33
4.7.3 To delete a panel set:..............................................................................................33
4.7.4 Adding NOTES to PANEL and A-LOG sets ............................................................ 33
4.7.5 Edit Notes Summary ...............................................................................................34
4.7.5.1 Using the Front Panel Keypad......................................................................... 35
4.7.5.2 Using the Optional Keyboard........................................................................... 35
5 Flaw Testing ......................................................................................................................... 36
5.1 Basic Flaw Testing ...................................................................................................... 36
5.2 Flaw Testing Calibration.............................................................................................. 37
5.3 DAC Operation............................................................................................................ 40
5.4 TCG Operation............................................................................................................ 42
5.5 Weld Inspection Using Trigonometry Mode ................................................................44
5.6 Weld Inspection Using the AWS Menu .......................................................................46
5.7 Evaluation of Pipe Imperfections using API 5UE ........................................................48
5.8 DGS/AVG Operation ...................................................................................................50
5.8.1 Theory ..................................................................................................................... 50
5.8.2 DGS/AVG Frequency, NFL and ERS...................................................................... 51
5.8.3 DGS/AVG dVK, Delay ............................................................................................. 51
5.8.4 DGS/AVG T-Loss, Ref dB and Mat dB.................................................................... 52
5.8.5 DGS/AVG ~ TBVEL, REF TYPE and REFSIZE......................................................53
5.8.6 DGS/AVG Calibration..............................................................................................54
5.8.6.1 Adjustment....................................................................................................... 55
5.8.7 Measurement ..........................................................................................................56
5.9 A-LOG, A-Scan Storage.............................................................................................. 57
5.9.1 To Store An A-Scan: ...............................................................................................57
5.9.2 To Recall an A-Scan: ..............................................................................................58
5.9.3 To Delete a Stored A-Scan .....................................................................................58
5.9.4 REF, Reference Waveform Comparisons ............................................................... 58
5.9.5 To Recall an A-Scan as a Reference Waveform:.................................................... 58
5.9.6 Contour & Peak Echo Dynamics ............................................................................. 59
6 Thickness Gauging...............................................................................................................61
6.1 Basic Thickness Gauging............................................................................................61
6.2 A-Cal ...........................................................................................................................63
6.3 TCG for Reliable Gauging ........................................................................................... 64
6.4 T-LOG Thickness Storage (Numeric)..........................................................................65
6.5 T-LOG Thickness Storage (Sequential & Download)..................................................66
6.6 T-FN Thickness Log Editing and Printing.................................................................... 68
6.6.1 To print a single Location: ....................................................................................... 68
6.6.2 To print all Locations in a single Block: ...................................................................68
6.6.3 To print all Blocks and all Locations: ....................................................................... 68
7 Power Supply ....................................................................................................................... 69
7.1 Lithium-Ion Battery Pack .............................................................................................69
7.1.1 Battery Cautions......................................................................................................69
7.2 Battery Charging .........................................................................................................70
7.2.1 Charging Caution ....................................................................................................70
8 Interface Connections ..........................................................................................................72
8.1 RS232 .........................................................................................................................72
8.2 Composite Video......................................................................................................... 73
Page ii
DFX-625 User’s Guide ~ Contents
8.3
Proportional Outputs....................................................................................................73
8.4 Synchronisation Outputs .............................................................................................73
9 Features of the DFX-625 ......................................................................................................74
9.1 Functional Testing Methods ........................................................................................74
10 Specifications........................................................................................................................75
11 Warranty ...............................................................................................................................78
12 Index .....................................................................................................................................79
Page iii
DFX-625 User’s Guide ~ How to Use This User’s Guide
1 How to Use This User’s Guide
This user’s guide has been designed so that a person with a good knowledge of the basics of
ultrasonic non-destructive testing may understand the operation and use of the features
offered by the DFX-625. The user is advised, however, of the important nature of ultrasonic
non-destructive testing and is referred to Section 2 for important information on the proper
use of this technology.
Section 1: How to Use This User’s Guide is this section.
Section 2: Disclaimers and Notices contains important information that must be understood
by users of the DFX-625
Section 3: Quick Start provides a user familiar with ultrasonic testing a means to operate the
instrument’s basic functions and to quickly achieve familiarity without having to understand
all of its features in detail.
Section: 4: Detailed Menu Description is an in-depth description of the menu items found in
the DFX-625 with brief descriptions of each item.
Section 5: Flaw Testing gives guidelines on performing flaw testing with examples of how to
calibrate the DFX-625 and how to set up the unit for DAC, TCG, DGS/AVG and how to use
the A-Scan storage facilities.
Section 6: Thickness Gauging gives guidelines on performing thickness measurements
including the calibration of the DFX-625, using TCG and how to use the thickness
measurement memory functions.
Section 7: Power Supply describes important aspects of using and caring for the battery
power supply so as to get maximum battery duration time and life.
Section 8: Interface Connections is for users who desire to operate the DFX-625 with
ancillary equipment.
Section 9: Features of the DFX-625 is a quick reference listing the pertinent characteristics of
the instrument and the various functional testing methods that may be used with the
instrument.
The function keys are shown throughout this manual as shown in Section 3.1, Front Panel
Controls.
1.1 Typographical Conventions
When describing front panel buttons the text is printed in this font.
When describing settings in the DFX-625 the text is.
printed in this font
Page 1
DFX-625 User’s Guide ~ Disclaimers and Notices
2 Disclaimers and Notices
The following information must be read and understood by users of the Dakota Ultrasonics
DFX-625 ultrasonic flaw detector and thickness gauge. Failure to follow these instructions
can lead to serious errors in test results or damage to the flaw detector. Decisions based on
erroneous results can lead to property damage, personal injury or death. Anyone using this
instrument should be fully qualified by their organization in the theory and practice of
ultrasonic testing, or under the direct supervision of such a person.
2.1 Specific Warnings
The DFX-625 contains a high-energy, precision pulser allowing optimum testing results to be
obtained by matching the pulse width to the probe characteristics. This circuitry may be
damaged by voltage spikes. It is recommended that the instrument be switched off, or the
pulser stopped (by pressing the
key) before changing transducers (probes).
2.2 General Warnings
Proper use of the ultrasonic test equipment requires three essential elements:
• Knowledge of the specific test or inspection and applicable test equipment.
• Selection of the correct test equipment based on knowledge of the application.
• Competent training of the instrument operator.
This user’s guide provides instruction in the basic operation of the DFX-625 flaw detector. In
addition to the methods included, many other factors can affect the use of this flaw detector.
Specific information regarding these factors is beyond the scope of this manual. The user
should refer to appropriate textbooks on the subject of ultrasonic testing and thickness
gauging for more detailed information.
2.3 Operator Training
Operators must receive adequate training before using this ultrasonic flaw detector.
Operators must be trained in general ultrasonic testing procedures and in the set-up and
performance required by each specific test or inspection. Operators must understand:
• Sound wave propagation theory.
• Effects of the velocity of sound in the test material.
• Behaviour of the sound wave at the interface of two different materials.
• Sound wave spread and mode conversion.
More specific information about operator training, qualification, certification and test
specifications can be obtained from technical societies, industry groups and government
agencies.
2.4 Testing Limitations
In ultrasonic testing, information is obtained only from within the confines of the sound beam
as it propagates into the test material. Operators must exercise great caution when making
inferences about the nature of the test material outside the limits of the sound beam. The
condition of materials can vary significantly and the results can be erratic if operators don’t
exercise good judgment.
2.5 Critical Operating Factors
The following procedures must be observed by all users of this ultrasonic flaw detector in
order to obtain proper and accurate results.
Page 2
DFX-625 User’s Guide ~ Disclaimers and Notices
2.5.1 Calibration of the Sound Velocity
An ultrasonic flaw detector operates on the principle of measuring the time of flight of a burst
of high frequency sound through the test piece as well as evaluating the amplitude of
reflected or transmitted echoes. The sound velocity of the test piece multiplies this time in
order to obtain an accurate distance or thickness reading. Since the actual sound velocity in
materials can vary from the published values, the best result is obtained when the instrument
is calibrated on a reference block made from the same material as the test piece. This block
should be flat, smooth and as thick as the maximum thickness expected of the test piece.
Users should also be aware that the sound velocity might not be constant throughout the test
piece due to effects such as heat-treating. This must be taken into consideration when
evaluating the results of ultrasonic thickness testing. The calibration should always be
checked after testing to minimize errors.
Page 3
DFX-625 User’s Guide ~ Disclaimers and Notices
2.5.2 Transducer (Probe) Zero Procedure
The transducer calibration procedures must be performed as described in this manual. The
calibration block must be clean, in good condition and free of noticeable wear. Failure to
perform the transducer zero and calibration procedure will cause inaccurate thickness
readings.
2.5.3 Flaw Detection Calibration
When performing flaw detection, it is important to note that the amplitude of indications is not
only related to the size of the discontinuity; the depth of a discontinuity below the test piece
surface will also have an effect on the amplitude due to characteristics of the sound beam
spread and near field zone of the transducer. In addition, the characteristics of the
discontinuity such as orientation and classification can alter the expected amplitude
response. For these reasons, calibration should be performed on test blocks made of the
same material as the test piece with artificial discontinuities within the range of size and
depth in the material to be detected. The user is again cautioned to refer to reference books
which are beyond the scope of this manual.
2.5.4 Effects of Temperature on Calibration
The sound velocity in test pieces and the transducer wear face changes with temperature
variations. All calibrations should be performed on site with test blocks at or near the same
temperature as that expected on the test piece, to minimize errors.
2.5.5 Transducer Condition
The transducer used for testing must be in good condition, without noticeable wear of the
front surface. The specified range of the transducer must encompass the complete range of
the thickness to be tested and/or the types of discontinuities to be investigated. The
temperature of the material to be tested must be within the transducer’s specified
temperature range.
2.5.6 Use of Couplant
Operators must be familiar with the use of ultrasonic couplant. Testing skills must be
developed so that couplant is used and applied in a consistent manner to eliminate variations
in couplant thickness which can cause errors and inaccurate readings. Calibration and
actual testing should be performed under similar coupling conditions, using a minimum
amount of couplant and applying consistent pressure to the transducer.
Page 4
DFX-625 User’s Guide ~ Disclaimers and Notices
2.6 Disclaimer of Liability
All statements, technical information and recommendations contained in this manual or any
other information supplied by Dakota Ultrasonics in connection with the use, features and
qualifications of the DFX-625 are based on tests believed to be reliable, but the accuracy or
completeness thereof is not guaranteed. Before using the product you should determine its
suitability for your intended use based on your knowledge of ultrasonic testing and the
characteristics of materials. You bear all risk in connection with the use of the product.
You are reminded that all warranties as to merchantability and fitness for purpose are
excluded from the contract under which the product and this manual have been supplied to
you. The Seller’s only obligation in this respect is to replace such quantity of the product
proved to be defective.
Neither the seller nor the manufacturer shall be liable either in contract or in tort for any direct
or indirect loss or damage (whether for loss of profit or otherwise), costs, expenses or other
claims for consequential or indirect compensation whatsoever (and whether caused by the
negligence of the company, its employees or agents or otherwise).
2.7 Electromagnetic Compatibility
This product conforms to the following European Directives:
Directive 2002/95/EC on the Restriction of the Use of certain Hazardous Substances in
Electrical and Electronic Equipment (RoHS)
Directive 2002/96/EC on Waste Electrical and Electronic Equipment (WEEE)
Low Voltage Directive (LVD) 73/23/EEC
CE Marking Directive 93/68/EEC
EMC Directive 89/336/EEC. However, in order to ensure the equipment meets the
requirements, the following should be read:
Warning: This is a “CLASS A” product. In a domestic environment, this product may cause
radio interference, in which case the user may be required to take adequate
measures.
Note: This product should not be connected to cables greater than three (3) meters in
length. If this is necessary, the installation may require further EMC testing to ensure
conformity.
The DFX-625 also complies with EN 12668-1, Non-destructive testing and verification of
ultrasonic examination equipment – Part 1: Instruments. For any questions relating to the
proper use of this product, please contact the manufacturer at the number indicated on page
i
Page 5
DFX-625 User’s Guide ~ Quick Start
3 Quick Start
3.1 Front Panel Controls & End Cap Connections
The front panel controls & end cap connections consist of a series sealed, pressure
sensitive, tactile buttons that allow the instrument settings to be changed and the movement
through the menus on the screen. An optional keyboard connected to the USB port can also
be used to navigate through the menus and make changes to the parameter values. A more
detailed description of each button is shown below followed by an overview of the front
panel:
When the term “highlighted” is used, it refers to text with a bright background and dark letters
which is the selected item.
Power on & off push button for switching the instrument on and off. Operates as a
toggle.
N.B Random lines or characters may be displayed for a second or two after switch
on, before the memory is initialized, this is normal.
The Menu button is used to display the 4 main menu levels (
MEMORY) on the right hand side of the screen. The MENU button can be pressed at
any time. To select the required sub-menu press the plain function button
associated with it. Corresponds to the “ESC” key when using a keyboard.
CAL, MEAS, UTIL and
These buttons move the highlighted cursor along the top of the screen left and right
to the sub menu to be selected. These are momentary buttons with no repeat. The
parameter boxes along the right hand side of the screen change as the sub menu is
selected. Corresponds to left and right arrows (w and x) when using a keyboard.
The four function buttons on the right side of the display are used to select the menu
boxes, which appear on the right side of the A-Trace. When a menu box is selected,
it will be highlighted. Pressing the button a second time will, on certain parameters,
display a drop-down list with a selection of values that can be chosen by using the
and buttons. When using a keyboard F1 to F4 correspond to the 4 white
buttons.
This button operates in connection with the function buttons next to the parameter
boxes to increase the value or step the selection in the positive direction. In the
case of transducer
Zero or Delay, it moves the signals to the right. This is a repeat
button with acceleration to facilitate quick scrolling of the value. Corresponds to up
arrow (y) when using a keyboard.
This button operates in connection with the function buttons next to the parameter
boxes to decrease the value or step the selection in the reverse direction. In the
case of transducer
ZERO or Delay, it moves the signals to the left. This is a repeat
button with acceleration to facilitate quick scrolling of the value. Corresponds to
down arrow (z) when using a keyboard.
This button changes the size of the steps that are used to adjust the parameters;
there are two sizes: small and large that are dependant on the parameter that is
being changed. The button toggles between the two sizes and the current state is
indicated by X for small and by XX for the larger step in the parameter box that is
being adjusted. Corresponds to the letter “I” when using the keyboard.
This button operates in conjunction with the memory menus to accept a store or to
accept a recall of a memory already in storage. In the print mode,
OK acts as the
print button. Corresponds to “Enter” or the return key.
Page 6
DFX-625 User’s Guide ~ Quick Start
Press this button once to select freeze mode for the A-Scan display. This is a useful
feature for holding an echo for evaluation. When in this mode, a box is highlighted
showing
FREEZE below the graticule.
Pressing the button a second time selects peak mode, which holds and updates all
echoes on the display during inspection. This feature allows an envelope or echo
dynamic pattern to be drawn on the screen which is useful for angle beam inspection
to locate the peak signal. When in this mode, a box is highlighted showing
PEAK
below the graticule.
If key lock is enabled from within the
selects
KEYLOCK mode, preventing accidental changing of parameters
UTIL menu, pressing the button a third time
Pressing the button a fourth time returns the A-Trace display to normal mode. This
is a momentary button with no repeat action. Corresponds to the letter “F” when
using the keyboard.
This button selects the help menu which overlays the display. The help menu
explains how the DFX-615 operates with a choice of three options:
Using the DFX-615
Description of the active menu
Calibration procedure.
Pressing the
HELP button again at any point in the help screens returns the display
to normal mode. The Help Screen also displays the Instrument serial number &
software version. Corresponds to “F5” when using a keyboard.
The full screen button is used to toggle between showing the A-Scan on the full
display and showing it with the menus and parameter boxes. If split screen is
enabled from the UTIL menu this button is used to display the A-Scan in the upper
half of the display and parameters in the lower half.
Press to select the dB step value of amplifier gain as 0.1, 0.5, 1, 2, 6, 10, 14, or
20dB. The selected value is indicated at the top right-hand corner of the gain box,
which is always located at the bottom right side of the screen. This is a momentary
button with no repeat. Corresponds to the letter “X” when using a keyboard.
Press to increment or decrement the gain value indicated in the gain box. This is
always located at the bottom right side of the screen. This is a repeat button with
acceleration to facilitate quick changing of the value. Corresponds to “Page Up” and
“Page Down” when using a keyboard.
Selects either reference or gain settings within the gain box. When reference is
selected, the increment and decrement buttons will change both the reference and
gain values together. This is a momentary button with no repeat. Corresponds to
the letter “R” when using a keyboard.
This button toggles between single and double element transducers. The user
should switch the unit off or stop the pulser by pressing the
FREEZE/PEAK key
before changing transducers. Corresponds to the letter “S” when using a keyboard.
BNC or LEMO 1 connector is the transmitter and receiver socket used for single
transducers or as the transmitter only, for twin or dual transducer operation. Refer to
back label.
BNC or LEMO 1 connector is the receiver socket used for twin or dual transducer
operation. Refer to back label.
A socket to connect various USB devices such as a printer, keyboard or the user’s
PC. Refer to back label.
Page 7
DFX-625 User’s Guide ~ Quick Start
A socket used to connect the battery charger for recharging the battery pack. A red
dot is provided on both the socket and plug to facilitate alignment. Refer to back
label.
Refer to Power Supply
for information on power supplies and charging of the battery
pack.
Page 8
DFX-625 User’s Guide ~ Quick Start
3.2 Flaw Detection
Perform the following steps to establish a basic flaw detection mode for the DFX-625. Units
shown are in inches. For metric units, select
corresponding values for the parameters.
1. Select a suitable transducer, preferably a 5MHz, half inch diameter narrow band.
METRIC UNITS from the UTIL menu and use the
2. When making a quick adjustment on a menu parameter, press the
button until the
double arrow appears next to the parameter name. This establishes the fast scroll using
the
3. In the
•
•
•
•
•
4. In the
•
•
5. In the
•
•
•
•
6. In the
•
•
•
•
and buttons.
CAL menu, set the following parameters:
ZERO to 0.000
VEL should be set the specimen material velocity.
RANGE to125 or other suitable value to cover the test range of interest.
DELAY to 0.000
GAIN to 50.0
AMP menu, set the following parameters:
DETECT to FULL
PRF to 150Hz
GATE1 menu, set the following parameters:
STATE to ON +VE
START to 10.0
WIDTH to 50 or other suitable value to cover the test range of interest.
LEVEL to 50.0
MEAS menu, set the following parameters:
MODE to DEPTH
TRIGGER to FLANK
HUD to OFF
T-MIN to OFF
The DFX-625 is now configured for basic flaw detection. Using an appropriate calibration
block, adjust the
GAIN parameter to establish the correct sensitivity. Adjust other parameters
as necessary to optimize the calibration. For more in-depth features of the DFX-625, see
Flaw Testing on page 36.
Page 9
DFX-625 User’s Guide ~ Quick Start
3.3 Thickness Gauging
Perform the following steps to establish a basic thickness-gauging mode for the DFX-625.
Units shown are in metric. For inch units, select
corresponding values for the parameters.
1. Select a suitable transducer, preferably a broadband, 5MHz, with a 10mm diameter.
2. Select an appropriate calibration block with at least three known thickness sections
covering the range to be inspected and made from the same material as the test piece.
INCHES from the UTIL menu and use the
3. When making a quick adjustment on a menu parameter, press the
button until the
double arrow appears next to the parameter name. This establishes the fast scroll using
the
4. In the
•
•
•
•
•
5. In the
•
•
6. In the
•
•
•
•
7. In the
•
•
•
•
and buttons.
CAL menu, set the following parameters:
ZERO can be left alone
VEL should be set to the specimen material velocity.
RANGE to 5” or other suitable value to cover the test range of interest.
DELAY to 0.000
GAIN to 50.0
AMP menu, set the following parameters:
DETECT to +VE HW
PRF to 150Hz
GATE1 menu, set the following parameters:
STATE to +VE
START to 10
WIDTH to 50 or other suitable value to cover the test range of interest.
LEVEL to 25.0
MEAS menu, set the following parameters:
MODE to DEPTH
TRIGGER to FLANK
HUD to ON
T-MIN to OFF
8. Calibrate the thickness readout on the selected calibration block using the procedure in
A-Cal on page 63.
The DFX-625 is now configured for basic thickness gauging. Adjust parameters as
necessary to optimize the calibration. For more in-depth features of the DFX-625, see
Thickness Gauging on page 61.
Page 10
DFX-625 User’s Guide ~ Quick Start
3.4 DFX-625 Memory
The settings of the DFX-625 always remain in memory when the instrument is turned off,
even if the battery pack is removed. That is, whatever the settings are just prior to turning
the instrument off will be the settings in place the next time the instrument is turned on.
At times it may be desirable to start with default settings. This is especially true when
beginning a new test procedure or going from flaw detection to a thickness gauging
procedure. Otherwise, it may be necessary to go through all of the menus to reset various
functions. A reset function is provided to facilitate the returning of all panel calibration
settings to the factory defaults.
3.4.1 Reset to factory defaults:
1. Switch the instrument off.
2. Depress the
FULL SCREEN button and hold while switching the instrument on until the
reset display is seen.
3. Press the
button to reset the instrument to factory defaults
NOTE: Before performing this procedure, be sure to save any favourite settings to memory
by using the procedure outlined in Storage & Recall of Calibration Setups on page 33.
NOTE: When resetting to factory default settings the following dialogue is displayed allowing
the user to choose imperial or metric defaults:
NOTE: The video always defaults to PAL.
3.4.2 Clearing the Memory
The DFX-625’s memory can store A-Scans, thicknesses and calibration set-ups. Erasing
these values accidentally could have serious consequences and should only be done after
suitable consideration. To erase the memory follow this sequence:
1. Switch the instrument off.
2. Depress the
display is seen.
MENU button and hold while switching the instrument on until the reset
3. Press the
button to clear the DFX-625’s memory
Page 11
DFX-625 User’s Guide ~ Detailed Menu Description
4 Detailed Menu Description
Before proceeding with this section, the user should be familiar with the front panel controls
described in section 3.1 Front Panel Controls on page 6. It is also assumed that the user
has a good understanding of the theory and practice of ultrasonic testing.
4.1 Menu Tree
This diagram represents the menu structure of the DFX-625; there are 4 main menu items
with sub-menus below. The sub-menus are described in the following section.
When The DFX-625 is switched on, an information screen is displayed momentarily showing
the instrument serial number and software version number while a self-test is performed as
shown below:
Page 12
DFX-625 User’s Guide ~Detailed Menu Description
4.2 Main Menu
After the information screen disappears the main menu selections are shown on the right
hand side of the screen. To select a particular menu press the function button to the right of
it. You can return to the main menu selection at any time by pressing the
4.2.1 Main Menu Selection
MENU button.
CAL
MEAS
UTIL
MEMORY
Note: The
Used to select the Calibration menu items: CAL,
AMP, GATE1, GATE2 and A_CAL
Used to select the Measurement menu items:
MEAS, CSC, PROBE, DAC, AVG, TCG, AWS and
API
Used to select the Utilities menu items: UTIL,
VIDEO, MISC, AGC, PRINT, P_O/P and CLOCK
Used to select the Memory menu items: PANEL,
A-LOG, REF, T-LOG and T-FN
REF/GAIN box always appears at the bottom right of the screen and can be
changed using the
Throughout the
menus there
are parameter
boxes that
have a thick
line
underneath
them as shown
here:
STEP, REF/GAIN and the and keys.
Pressing the grey
button next to one
of these parameter
boxes produces a
drop-down list as
shown here:
Press the grey
button again to
remove the dropdown list after the
required value has
been selected.
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DFX-625 User’s Guide ~ Detailed Menu Description
4.3 CAL Menu
The CAL menu is the most used menu and contains those items that allow the DFX-625 to
be easily calibrated. For full instruction on how to perform a calibration see Flaw Testing
Calibration on page 37
4.3.1 Calibration Menu
ZERO
Used to calibrate the screen and thickness readout
for zero offsets that are inherently different for
each transducer. Units are microseconds in both
mm and inch modes.
VEL
Used to calibrate the screen and thickness span
readout based on the velocity of sound in the test
material. Units are meters per second in mm
mode and inches per microsecond in inch mode.
RANGE
Used to set the full screen width of the horizontal
A-Trace in mm, inches, or microseconds
depending on the Units chosen in the
The range is 1mm to 20 meters (0.05 to 800
inches).
DELAY
Used to set the delay or offset of the left side of the
A-Trace for viewing of a portion of a signal. The
range is 0 to 20 meters (0 to 800 inches).
4.3.2 Amplifier Menu
FREQ
Used to set the centre frequency band of the
amplifier to match the transducer. Ranges are 1,
2.5, 5 & 10MHz narrow bands and 1.5 – 15MHz
wide band.
UTIL menu.
DETECT
REJECT
PRF MAX
Used to set the display mode for the desired
rectification of the signals from
full wave),
half-wave) and
RF ( un-rectified), -VE HW (negative
+VE HW (positive half-wave)
FULL (rectified
Used to remove low level noise from the ATrace. Reject is linear and is adjustable from 0
up to 50% of full screen height. The
REJECT
LED is lit when a reject is active.
Used to set the maximum pulse repetition
frequency. Selectable values are from 35 to 100
in 5Hz steps, from 100 to 1,000 in 50Hz steps.
Lower values will reduce ghosting and noise
echoes.
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DFX-625 User’s Guide ~Detailed Menu Description
4.3.3 GATE1 & GATE2 Menus
There are two gates available in the DFX-625 with slightly different options depending on the
gate and the measurement mode chosen. The following describes the available settings for
each gate with the differences between the gates stated. The gates can be identified by the
fact that gate 1 has the number “1” above the line and gate 2 has the number “2” above it.
STATE
START
Set the state of the gate as follows:
+VE: The alarm triggers when an echo in
the gate exceeds the threshold level.
-VE: The alarm triggers when an echo in
the gate falls below the threshold
level. Usually used to monitor for loss
of back wall echo.
EXPAND: Expands the gate width to fill the
horizontal display width. Only applies
to gate 1.
OFF: Switches the gate off.
-VE DLY: (Gate 2 only) This fourth state on gate
two implements a gate to alarm delay
of 600 milliseconds. This requires that
the signal be lost from the gate for a
continuous period of 600 milliseconds
before the alarm is activated. This is
implemented for the alarm LED,
buzzer and external alarm output via
the proportional output connector.
Used to set the start position of the gate relative
to the initial pulse.
Units are mm or inches and range is from 0 to
the full time base of the horizontal display.
WIDTH
Used to set the width of the gate. Units are mm
or inches and range is from 0.15mm (0.001 inch),
depending on the range selected, to the full time
base of the horizontal display.
LEVEL
Used to adjust the alarm threshold level, which
corresponds to the vertical height on the A-Trace.
Adjustable in 0.5% or 2% steps from 0% to 100%
full screen height.
4.3.4 A-CAL Menu
This menu provides automatic calibration of sound velocity and
transducer zero. Gate 1 is used to select the reference echoes. See
A-Cal on page 63 for a full procedure.
DIST1
DIST2
ACCEPT
The actual distance to the first or thinnest
reference echo in the calibration block.
The actual distance to the second or thickest
reference echo in the calibration block
After pressing OK to accept DIST1 and DIST2.
Press
OK when ACCEPT CAL is highlighted.
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DFX-625 User’s Guide ~ Detailed Menu Description
START
Used to adjust the start of the gate to assure that
the first and second echoes are measured
Page 16
DFX-625 User’s Guide ~Detailed Menu Description
4.4 MEAS Menu
The menus in this section allow the various measurement techniques to be configured; these
include the general measurement set-up and specialist methods such as DAC, AVG, TCG,
AWS and API. Select the
4.4.1 Measurement Menu
In the measurement menu, the top selection box shows the selected
measurement mode and the remaining three selection boxes vary
depending on the mode selected as follows:
MEAS menu at any time by pressing the MENU button.
MODE:
MONITOR
MODE:
DEPTH
TRIGGER
HUD
In this mode, gates 1 and 2 act as two
independent monitor gates
In this mode, gate 1 functions as a depth or
thickness monitor and displays the depth (D:)
and height (H:) of the first signal after the start of
the gate that reaches or exceeds the gate level
threshold. Values are displayed in a highlighted
box below the A-Trace.
Used to select the depth or thickness
measurement to the
echo after the start of the gate or the
FLANK (left edge) of the first
PEAK
measurement within the gate i.e. the largest
value in the gate.
When turned
ON, provides a large, Head-Up
Display of the depth or thickness reading at the
top right of the A-Trace. The
button
sequences the selections as follows:
G1-G2 E-E DEPTH TRIG
OFF OFF OFF OFF
DIST DIST DIST DIST
DIST + DIST + HEIGHT HEIGHT
DIST + DIST +
HEIGHT + HEIGHT +
¾ +
 +
¾
Â
T-MIN
When turned ON, the depth or thickness reading
will freeze that last minimum or lowest value
measured. To reset, toggle the function to OFF
and then ON. Only available in the DEPTH
mode.
MODE:
E-E
In this mode, gate 1 functions as a thickness
monitor and measures the thickness between the
first signal in the gate and the second signal in
the gate that reaches or exceeds the level
threshold. A second bar is shown representing
the blanking (see BLANK)
BLANK
This function sets the blanking distance, as a
percentage of the total gate width, which is a
Page 17
DFX-625 User’s Guide ~ Detailed Menu Description
blind zone after the first echo, after which a
second echo can be measured. This helps to
eliminate undesired noise in the first echo from
being measured, as thickness but will limit the
minimum thickness capability if set too large
MODE:
G-G
MODE:
TRIG
THICK
This is similar in concept to E-E mode, but uses
gates 1 & 2, allowing the thresholds for the two
gate measurements to be completely
independent.
The Trigonometry mode is used with angle beam
transducers for weld inspection to calculate the
three important measurements based on the
echo position: the Beam path distance (Â:), the
Surface distance (¼:), and the Depth distance
(¾:) from the index point of the transducer.
Set to the thickness of the material being tested
to account for multiple skips of the angled sound
beam in the test material.
Page 18
DFX-625 User’s Guide ~Detailed Menu Description
4.4.2 CSC (Curved Surface Correction)
This menu allows the user to configure the Curved Surface Correction
(CSC) parameters. This feature normally used when testing pipes and
other curved surfaces. In order for the correction to be made the correct
wall thickness must be selected in the
selected in the
MEAS menu.
THICK option when TRIG is
MODE
Surface
Turn CSC ON or OFF.
Choose CONCAVE for internal surfaces or
CONVEX for external surfaces
RAD
Select the radius of the curvature.
4.4.3 PROBE Menu
ANGLE
X-OFFSET
1/2 SKIP
Set to the nominal refracted angle of the
transducer to calibrate the Surface and Depth
measurements
Used to enter the distance from probe emission
point to front of probe case. This is used by the
TRIG function in MEAS menu to give the
surface distance.
Used as a quick way to turn on the ½ skip
graticule.
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