Elcometer 205 User manual

en
Elcometer 205
Elcometer 206 • 206DL
Ultrasonic Thickness Gauge
Operating Instructions
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The Elcometer 205, 206 and 206DL Ultrasonic Thickness Gauges have been tested in
accordance with EU regulations governing Electro-magnetic compliance and they meet the
required directives.
is a registered trademark of Elcometer Limited. All other trademarks acknowledged.
Material Safety Data Sheets for the ultrasonic couplant supplied with the Elcometer 205, 206 & 206DL
available as an accessory is available to download via our website :
Elcometer Ultrasonic Couplant Material Safety Data Sheet:
www.elcometer.com/images/MSDS/elcometer_ultrasonic_couplant.pdf
Elcometer Ultrasonic Couplant (High Temperature) Material Safety Data Sheet:
www.elcometer.com/images/MSDS/elcometer_ultrasonic_couplant_hi_temp.pdf
© Copyright Elcometer Limited. 2009/2012. All rights reserved. No part of this document may be
reproduced, transmitted, transcribed, stored (in a retrieval system or otherwise) or translated into any
language, in any form or by any means (electronic, mechanical, magnetic, optical, manual or otherwise)
without the prior written permission of Elcometer Limited.
A copy of this Instruction Manual is available for download on our Website via www.elcometer.com.
Doc.No. TMA-0222 Issue 06
Text with Cover No: 4888
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CONTENTS
Section Page
1 About your gauge . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3
2 Quick-start . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6
3 Getting started. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7
4 Taking a reading . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14
5 Setting the zero point (probe-zero) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 16
6 Calibration . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 18
7 Set-up options. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 22
8 Transferring readings to a computer . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 28
9 Using the data logger . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 29
10 Storage. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 34
11 Maintenance . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 34
12 Technical specification. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 35
13 Spares . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 36
14 Related equipment . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 37
15 Warranty. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 37
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APPENDICES
Transducers . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 39
Condition and preparation of surfaces . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 42
Application notes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 43
Data transfer software . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 45
Sound velocities of common materials . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 47
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Thank you for purchasing this Elcometer 205/206/206DL Ultrasonic Thickness Gauge. Welcome to
Elcometer.
Elcometer are world leaders in the design, manufacture and supply of coatings inspection equipment. Our
products cover all aspects of coating inspection, from development through application to post application
inspection.
The Elcometer 205, 206 and 206DL Ultrasonic Thickness Gauges are world beating products. With the
purchase of this gauge you now have access to the worldwide service and support network of Elcometer.
For more information visit our website at www.elcometer.com.
1 ABOUT YOUR GAUGE
The Elcometer 205, 206 and 206DL Ultrasonic Thickness Gauges are handheld gauges for fast and
accurate measurement of material thickness.
Your gauge is capable of measuring the thickness of various materials with accuracy as high as ± 0.1 mm
(± 0.004"). The principal 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.
There are three versions of the gauge:
• The Elcometer 205 is the basic model.
• The Elcometer 206 includes all features of the 205 plus differential mode, an alarm and data output.
• The Elcometer 206DL model includes all the features of the Elcometer 206 model plus a data-logging
(memory) facility which allows readings to be stored in batches before being downloaded to a
computer.
This manual describes the operation of all three models - Elcometer 205, 206 and 206DL.
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1.1 STANDARDS
The Elcometer 205, 206 & 206DL can be used in accordance with the following International Standards
ASTM E 797, EN 14127 & EN 15317.
1.2 WHAT THIS BOX CONTAINS
• Elcometer 205, 206 or 206DL Gauge
• Bottle of couplant
• Battery, 2 x
• Carrying case
• Operating instructions
• CD with data transfer and data collection software - 206DL only
• Data transfer cable - 206DL only
Note: The box does not include a transducer; these must be ordered separately. To order a transducer,
contact Elcometer or your local Elcometer supplier.
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Your gauge is packed in a cardboard and foam package. Please ensure that this packaging is disposed of
in an environmentally sensitive manner. Please consult your Local Environmental Authority for further
guidance.
Figure 1. Elcometer 205 - 206 - 206DL
1.3 FEATURES OF THE GAUGE
SCAN MODE: Identifies the minimum thickness over a large area while moving the transducer over the
surface. While the transducer is in contact with the material being measured the smallest value is held in
memory and displayed when scanning is complete.
Elcometer 206
Ultrasonic Thickness Gauge
R
CAL
SEND
ALRM
DIFF
PRB
0
IN
MM ON OFF
SCAN
Elcometer 206 DL
Ultrasonic Thickness Gauge
R
CLR
MEM
SEND
MODE
CAL
PRB
0
Data Logger
ON
OFF
Elcometer 205
Ultrasonic Thickness Gauge
R
CAL PRB
0
ON
OFF
IN
MM
SCAN
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ALARM: Allows the user to set a target so that an audible and visual alarm operates when taking
measurements. If the measurement falls below a pre-set nominal (target) value a red LED will light and the
beeper sounds. A green LED will light to indicate an acceptable thickness.
DATA OUTPUT: Allows the user to send data direct to a printer or PC (data transfer cable required).
DATA-LOGGING: Memory capacity of up to 1000 readings. Readings are stored in up to 10 batches each
containing up to 100 readings. Batches may be transferred to a PC using supplied software.
To maximise the benefits of your new Elcometer Ultrasonic Thickness Gauge, please take some
time to read these Operating Instructions. Do not hesitate to contact Elcometer or your Elcometer
supplier if you have any questions.
2 QUICK-START
To quickly configure the gauge and start taking readings:
1. Fit batteries: see page 7
2. Fit transducer: see page 8
3. Switch on: see page 9/11
4. Try taking a reading: see page 14
5. Set zero point: see page 16
6. Adjust calibration: see page 18
The gauge is now configured and ready to use.
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3 GETTING STARTED
3.1 FITTING BATTERIES
Your gauge may be used with dry cell batteries or rechargeable batteries.
2 x LR6 (AA) alkaline batteries are supplied in the kit.
To fit or replace batteries:
7. Locate battery compartment cover (Figure 2) at top of gauge.
8. Unscrew battery compartment cover.
9. Referring to battery polarity instructions on rear of gauge, insert
batteries into gauge ensuring correct polarity.
10. Replace battery compartment cover.
Remove the batteries from the gauge if it is to remain unused for a long
period of time. This will prevent damage to the gauge in the event of
malfunction of the batteries.
When the battery voltage is low the entire display will start to flash. When
this occurs the batteries should be replaced.
Note: Alkaline batteries must be disposed of carefully to avoid
environmental contamination. Please consult your local environmental
authority for information on disposal in your region.
Do not dispose of any batteries in fire.
Elcometer 208
Ultrasonic Thickness Gauge
R
CAL
SEND
A
LRM
PRB
0
IN
MM ON OFF
SCAN
DUAL
MULTI
Elcometer 206
Ultrasonic Thickness Gauge
R
CAL
SEND
A
LRM
DIFF
PRB
0
IN
MM ON OFF
SCAN
Battery
compartment
cover
Figure 2. Fitting batteries
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3.2 THE TRANSDUCER
The transducer (Figure 3) transmits and receives ultrasonic
sound waves that the gauge uses to calculate the thickness of
the material being measured.
The transducer connects to the gauge via the attached cable,
and two coaxial connectors. When using transducers
manufactured by Elcometer, the orientation of the dual coaxial
connectors is not critical; either plug may be fitted to either
socket.
The transducer must be used correctly in order for the gauge
to produce accurate, reliable measurements.
Figure 4 shows the two semicircles of the wearface and the
barrier separating them. One of the semicircles transmits
ultrasonic sound into the material being measured, and the
other semicircle receives the sound echoes back into the
transducer. When the transducer is placed against the
material being measured, it is the area directly beneath the
centre of the wearface that is being measured.
Figure 3. Typical transducer
Wearface
Figure 4. Transducer - bottom view
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3.3 THE KEYPAD
ELCOMETER 205 (6 BUTTONS) AND 206 (9 BUTTONS)
Press to switch the gauge on or off.
When switching off, the gauge retains all of its settings.
If the gauge is idle for 5 minutes, it will switch itself off.
205
206
Press to zero the gauge.
See “Setting the zero point (probe-zero)” on page 16. 205
206
Press to adjust calibration.
See “Calibration” on page 18. 205
206
Press to change units (metric/imperial) 205
206
a) Increases values on the display
(press and hold to change values quickly). 205
206
b) Switches SCAN measurement on and off.
See “Scan mode” on page 22.
a) Decreases values on the display
(press and hold to change values quickly). 205
206
b) Switches the display backlight between three settings; on,
off and auto. See “Backlight” on page 27.
ON
OFF
PRB
0
CAL
IN
MM
SCAN
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a) Press and hold when switching the gauge on to switch the
audible beeper on or off. 206
b) Press to toggle the alarm on or off, and to adjust the
nominal thickness value. See “Alarm” on page 25.
Press to toggle the DIFFERENTIAL mode on or off, and to
adjust the nominal thickness value.
See “Differential Mode” on page 23. 206
Press to send the displayed thickness measurement to an
external storage device via the RS232 port.
See “Transferring data” on page 29. 206
ALRM
DIFF
SEND
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ELCOMETER 206DL
Press to switch the gauge on or off.
When switching off, the gauge retains all of its settings.
If the gauge is idle for 5 minutes, it will switch itself off.
Press to zero the gauge.
See “Setting the zero point (probe-zero)” on page 16.
Press to adjust calibration.
See “Calibration” on page 18.
Press to adjust the features and settings of the gauge (alarm,
scan, units, backlight, and beeper).
a) Increases values on the display
(press and hold to change values quickly).
b) Scrolls up through features and settings of the gauge and
through files, memory locations, and functions of the data logger.
a) Decreases values on the display
(press and hold to change values quickly).
b) Scrolls down through features and settings of the gauge and
through files, memory locations, and functions of the data logger.
Press to switch on/off data logging (memory).
See “Using the data logger” on page 29.
ON
OFF
PRB
0
CAL
MODE
MEM
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Press when data logger is switched on to clear the contents of an
entire batch, or an individual memory location.
The CLR key is also used to send an obstruct message (ObSt) to
an individual memory location. The ObSt symbol would indicate
that the user was unable to take a reading at a particular location.
See “Using the data logger” on page 29.
Press to send the displayed thickness measurement to an internal
memory location or an external storage device via the RS232 port.
See “Transferring data” on page 29.
The SEND key is also used to select data logging functions in the
Elcometer 206DL.
CLR
SEND
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3.4 THE DISPLAY
Stability indicator
Refer to “Read display” on page 15 and “Transducers” on page 39 for information on how to achieve a
stable measurement.
One bar - no readings are being taken
Less than 5 bars - reading is unstable and may be
inaccurate
More than 5 bars - reading is stable
INMM/ s µ
Stability
indicator
(see
below)
Units
(IN, MM
IN/µs,
MM/s)
Thickness value/
Menu items
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3.5 FRONT PANEL LIGHTS
Green light illuminates when:
• The alarm mode is active, and
• the measured thickness is greater than the alarm value.
Red light illuminates when:
• The alarm mode is active, and
• the measured thickness is less than the alarm value.
4 TAKING A READING
Disclaimer: Inherent in ultrasonic thickness measurement is the possibility that the instrument will use the
second echo rather than the first echo from the back surface of the material being measured while in
standard pulse-echo mode. This may result in a thickness reading which is TWICE what it should be.
The responsibility for proper use of the instrument and recognition of these types of phenomenon rests
solely with the user of the instrument.
4.1 Before you start
•Set the zero point of the gauge.
See “Setting the zero point (probe-zero)” on page 16.
•Calibrate the gauge.
See “Calibration” on page 18.
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•Prepare the surface.
See “Condition and preparation of surfaces” on page 42.
1. Apply couplant
For the gauge to work correctly there must be no air gaps between the transducer and the surface of
the material to be measured. This is achieved using a material called a couplant.
Before the transducer is placed on the surface, put a small amount of the couplant supplied with the
gauge on the surface of the material. Typically a single drop is sufficient.
2. Place transducer onto surface of material to be measured
Press the transducer wearface into the couplant. Moderate pressure on the top of the transducer using
the thumb or index finger is sufficient; it is only necessary to keep the transducer stationary and the
wearface seated flat against the surface of the material.
3. Read display
If six or seven bars of the stability indicator are showing, the display will be reading the correct
thickness of the material directly beneath the transducer.
If the stability indicator has fewer than five bars showing, or the numbers on the display seem erratic,
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.
The gauge will perform four measurements every second when the transducer is in contact with the
surface of the material. The display is updated as each reading is taken.
4. Remove transducer from surface
The display will show the last measurement made.
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Note: 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 gauge 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. If this happens, take the reading again using less couplant.
5 SETTING THE ZERO POINT (PROBE-ZERO)
Setting the zero point of the gauge is important for the same reason that setting the zero on a mechanical
micrometer is important. If the zero point of the gauge is not set correctly, allof the measurements the gauge
makes will be in error by some fixed number. When the zero point of the gauge is set, this fixed error value
is measured and automatically corrected for in all subsequent measurements.
To set the zero point:
1. Plug the transducer into the gauge ensuring that the connectors are fully engaged. Check that the
wearface of the transducer is clean and free of any debris.
2. Switch on the gauge.
3. The battery compartment cover on the top end of the gauge acts as a metal ‘probe-disc’. Apply a
single droplet of ultrasonic couplant to the top of this disc.
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4. Press the transducer against the probe-disc, making sure that the transducer is flat against the surface
(Figure 5). The display should show some thickness value, and nearly all the bars of the stability
indicator should be illuminated.
Figure 5. Transducer pressed against probe-disc
5. While the transducer is firmly coupled to the probe-disc, press the PRB-0 key on the keypad. The
gauge will display ‘Prb0’ while it is calculating the zero point.
6. Remove the transducer from the probe-disc.
When setting the zero point, the gauge will always use the sound-velocity value of the built-in probe-disc,
even if some other velocity value has been entered for making measurements.
Although the gauge will remember the last zero point, it is generally a good idea to set the zero point
whenever the gauge is switched on, as well as any time a different transducer is used. This will ensure that
the zero point of the instrument is always correct.
Elcometer 208
Elcometer 206
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6 CALIBRATION
In order for the gauge to make accurate measurements, it must be set to the correct sound-velocity for the
material being measured.
Different types of material have different sound-velocities. For example, the velocity of sound through steel
is 5918 m/s (about 0.233 in/µs) and the velocity of sound through aluminium is 6350 m/s (about 0.248 in/
µs).
If the gauge is not set to the correct sound-velocity, all of the measurements the gauge makes will be
erroneous by some fixed percentage.
There are three methods of calibrating your gauge:
One-point CALIBRATION: This is the simplest and most commonly used calibration procedure - optimising
linearity over large ranges. One-point calibration is carried out using a known thickness.
Two-point CALIBRATION: This allows for greater accuracy over small ranges. Two-point calibration is carried
out using two known thicknesses.
Known velocity CALIBRATION: The sound-velocity of the material being measured is entered directly into
the gauge.
Note: One-point and two-point calibrations must be performed on material with the paint or coating
removed. Failure to remove the paint or coating prior to calibration will result in a multi-material velocity
calculation that may be different from the actual material velocity intended to be measured.
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