Dakota Ultrasonics MX5 Operating Manual

OPERATION MANUAL

P/N P

-

115

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0002

Rev.

1.90, Jan

uary

2008

DAKOTA ULTRASONICS MODEL MX-5 DL ULTRASONIC THICKNESS GAUGE

Dakota Ultrasonics

Copyright  2008 Dakota Ultrasonics. All rights reserved.

No part of this publication may be reproduced, translated into another
language, stored in a retrieval system, or transmitted in any form or by any
means; electronic, mechanical, photocopying, recording, or otherwise,
without the prior written consent of Dakota Ultrasonics.

Every precaution has been taken in the preparation of this publication.
Dakota Ultrasonics assumes no responsibility for errors or omissions.
Neither is any liability assumed for damages resulting from the use of
information contained herein.

Any brand or product names mentioned herein are used for identification
purposes only, and are trademarks or registered trademarks of their
respective holders.

1500 Green Hills Road, #107 Scotts Valley, CA 95066 USA

Tel [phone] Fax [phone]

www.dakotaultrasonics.com

MX-5 DL Ultrasonic Thickness Gauge

CONTENTS

INTRODU CTION
OPERATION

THE KEYPAD
THE DISPLAY
THE TRANSDUCER
MAKING MEASUREMENTS
CONDITION AND PREPARATION OF SURFACES
PROBE ZERO
CALIBRATION
UNITS, BACKLIGHT, SCAN MODE, ALARM MODE, DIFF

MODE, BEEPER, RS232 PORT & DATA LOGGER
TRANSDUCER SELECTION
APPENDIX A: PRODUCT SPECIFICATIONS

1
3
3
7

9
10
12
13
14
18

30
34

APPENDIX B: APPLICATION NOTES
APPENDIX C: SOUND VELOCITIES OF COMMON MATERIALS
WARRANTY INFORMATION

36
40
42

DISCLAIMER

Inherent in ultrasonic thickness measurement is the possibility that the
instrument will use the second rather than the first echo from the back
surface of the material being measured. This may result in a thickness
reading that is TWICE what it should be. Responsibility for proper use of
the instrument and recognition of this phenomenon rests solely with the
user of the instrument.

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MX-5 DL Ultrasonic Thickness Gauge

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INTRODUCTION

The Dakota Ultrasonics model MX- 5 DL is a precision Ultrasonic
Micrometer. Based on the same operating principles as SONAR, the MX-5
DL is capable of measuring the thickness of various materials with

accuracy as high as ± 0.001 inches, or ± 0.01 millimeters. The principle
advantage of ultrasonic measurement over traditional methods is that
ultrasonic measurements can be performed with access to only one side of
the material being measured.

This manual is presented in three sections. The first section covers
operation of the MX-5 DL, and explains the keypad controls and display.
The second section provides guidelines in selecting a transducer for a
specific application. The last section provides application notes and a table
of sound velocity values for various materials.

Dakota Ultrasonics maintains a customer support resource in order to
assist users with questions or difficulties not covered in this manual.
Customer support may be reached at any of the following:

• Dakota Ultrasonics, 1500 Green Hills Road, #107
Scotts Valley, CA 95066 USA

• Telephone: [phone]

• Facsimile: [phone]

• www.dakotaultrasonics.com

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MX-5 DL Ultrasonic Thickness Gauge

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OPERATION

The MX-5 DL interacts with the operator through the membrane keypad
and the LCD display. The functions of the various keys on the keypad are
detailed below, followed by an explanation of the display and its various
symbols.

The Keypad

This key is used to turn the MX-5 DL on and off. When the tool is
turned ON, it will first perform a brief display test by illuminating all of the
segments in the display. After one second, the tool will display the internal
software version number and the current file location and status. After
displaying the version number, the display will show "0.000" (or "0.00" if
using metric units), indicating the tool is ready for use.

The MX-5 DL is turned OFF by pressing the ON/OFF key. The tool has
a special memory that retains all of its settings even when the power is off.
The tool also features an auto-powerdown mode designed to conserve
battery life. If the tool is idle for 5 minutes, it will turn itself off.

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The PRB-0 key is used to "zero" the MX-5 DL in much the same way
that a mechanical micrometer is zeroed. If the tool is not zeroed correctly,

all of the measurements that the tool makes may be in error by some fixed
value. Refer to page 13 for an explanation of this important procedure.

The CAL key is used to enter and exit the MX-5 DL's calibration mode.
This mode is used to adjust the sound-velocity value that the MX-5 DL will
use when calculating thickness. The tool will either calculate the sound­velocity from a sample of the material being measured, or allow a known
velocity value to be entered directly. Refer to page 14 for an explanation of
the two CAL functions available.

The MODE key is used to toggle through the various features and
settings of the MX-5 DL ( alarm mode, beeper, back light, units, scan

mode, and differential mode ). The MODE key is used in conjunction with
the arrow and send keys to enable/disable the features and settings.

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The UP arrow key has three functions. When the MX-5 DL is in
calibration mode, this key is used to increase numeric values on the
display. An auto-repeat function is built in, so that when the key is held
down, numeric values will increment at an increasing rate. When MODE is
activated, the UP arrow key scrolls through the various features and
settings of the MX-5 DL. When the data logging feature has been activated
by pressing the MEM key, the UP arrow is used to scroll through the
various files, storage locations, and functions of the data logg er. Refer to
page 24 for further information regarding the use of the UP arrow key and
the data logger.

The DOWN arrow key has three functions. When the MX-5 DL is in the
CAL mode, this key is used to decrease numeric values on the display. An
auto-repeat function is built in, so that when the key is held down, numeric
values will decrement at an increasing rate. When MODE is activated, the

DOWN arrow scrolls through the various features and settings of the MX-5
DL. When the data logging feature has been activated by pressing the

MEM key, the UP arrow is used to scroll through the various files, storage
locations, and functions of the data logger. Refer to page 24 for further
information regarding the use of the DOWN arrow key and the data logger.

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The MEM key enables/disables the data logging feature of the MX-5
DL. This key is used in conjunction with the UP/DOWN arrows, SEND,
AND CLR keys (hi-lighted in green). The combination of these keys

control the data logging features of the MX-5 DL. Refer to the section on
data logging page 24.

The CLR key is specifically used with the data logging feature of the
MX-5 DL. This key clears the contents of an entire file, or individual
storage locations. The CLR key is also used to send an obstruct (ObSt) to
an individual storage location. The ObSt symbol would indicate that a the
user was unable to take a reading at a particular location. Refer to the
section on data logging page 26.

The SEND key is used for sending data to internal storage locations,
and external peripheral devices ( serial printer / computer ). The SEND key
is also used to select data logging functions in the MX-5 DL page 24.

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The Display

The numeric portion of the display consists of 4 complete digits
preceded by a leadi ng "1", and is used to display numeric values, as well
as occasional simple words, to indicate the status of various settings.
When the MX-5 DL is displaying thickness measurements, the display will
hold the last value measured, until a new measurement is made.
Additionally, when the battery voltage is low, the entire display will begin to
flash. When this occurs, the batteries should be replaced.

These eight vertical bars form the Stability Indicator. When the MX-5
DL is idle, only the left -most bar and the underline will be on. While the
gauge is taking a measurement, six or seven of the bars should be on. If

fewer than five bars are on, the MX-5 DL is having difficulty achieving a
stable measurement, and the thickness value displayed will most likel y be
erroneous.

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When the IN symbol is on, the MX-5 DL is displaying a thickness value
in inches. The maximum thickness that can be displayed is 19.999 inches.

When the MM symbol is on, the MX-5 DL is displaying a thickness
value in millimeters. If the displayed thickness exceeds 199.99 millimeters,
the decimal point will shift automatically to the right, allowing values up to

1999.9 millimeters to be displayed.

When the IN symbol is on, in conjunction with the /µs symbol, the MX-5
DL is displaying a sound-velocity value in inches-per-microsecond.

When the M symbol is on, in conjunction with the /s symbol, the MX-5
DL is displaying a sound-velocity value in meters-per-second.

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The Transducer

The transducer is the "business end" of the MX-5 DL. It transmits and
receives ultrasonic sound waves that the MX-5 DL uses to calculate the
thickness of the material being measured. The transducer connects to the
MX-5 DL via the attached cable, and two coaxial connectors. When using
transducers manufactured by Dakota Ultrasonics, the orientation of the
dual coaxial connectors is not critical: either plug may be fitted to either
socket in the MX-5 DL.

The transducer must be used correctly in order for the MX-5 DL to
produce accurate, reliable measurements. Below is a short description of

the transducer, followed by instructions for its use.

This is a bottom view of a typical transducer. The two semicircles of the
wearface are visible, as is the barrier separating them. One of the
semicircles is responsibl e for conducting ultrasonic sound into the material
being measured, and the other semicircle is responsible for conducting the
echoed sound back into the transducer. When the transducer is placed
against the material being measured, it is the area directly beneath the
center of the wearface that is being measured.

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This is a top view of a typical transducer. Press against the top with the
thumb or index finger to hold the transducer in place. Moderate pressure is
sufficient, as it is only necessary to keep the transducer stationary, and the
wearface seated flat against the surface of the material being measured.

Making Measurements

In order for the transducer to do its job, there must be no air gaps
between the wear-face and the surface of the material being measured.
This is accomplished with the use of a "coupling" fluid, commonly called
"couplant". This fluid serves to "couple", or transfer, the ultrasonic sound
waves from the transducer, into the material, and back again. Before
attempting to make a measurement, a small amount of couplant should be
applied to the surface of the material being measured. Typically, a single
droplet of couplant is sufficient.

After applying couplant, press the transducer (wearface down) firmly
against the area to be measured. The Stability Indicator should have six or
seven bars darkened, and a number should appear in the display. If the
MX-5 DL has been properly "zeroed" (see page 13) and set to the correct
sound velocity (see page 14), the number in the display will indicate the
actual thickness of the material directly beneath the transducer.

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If the Stability Indicator has fewer than five bars darkened, or the
numbers on the display seem erratic, first check to make sure that there is
an adequate film of couplant beneath the transducer, and that the
transducer is seated flat against the material. If the condition persists, it
may be necessary to select a different transducer (size or frequency) for
the material being measured. See page 30 for information on transducer
selection.

While the transducer is in contact with the material that is being
measured, the MX-5 DL will perform four measurements every second,
updating its display as it does so. When the transducer is removed from
the surface, the display will hold the last measurement made.

IMPORTANT

Occasionally, a small film of couplant will be drawn out between the
transducer and the surface as the transducer is removed. When this
happens, the MX-5 DL may perform a measurement through this couplant
film, resulting in a measurement that is larger or smaller than it should be.
This phenomenon is obvious when one thickness value is observed while
the transducer is in place, and another value is observed after the
transducer is removed.