Elcometer CG60DL User manual

en
Model CG60
Model CG60DL
Corrosion Gauge
Operating Instructions
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This product meets the Electromagnetic Compatibility Directive.
The product is Class A, Group 1 ISM equipment according to CISPR 11.
Group 1 ISM product: A product in which there is intentionally generated and/or used conductively coupled radio-
frequency energy which is necessary for the internal functioning of the equipment itself.
Class A product are suitable for use in all establishments other than domestic and those directly connected to a
low voltage power supply network which supplies buildings used for domestic purposes.
is a registered trademark of Elcometer Limited.
All other trademarks acknowledged.
© Copyright Elcometer Limited. 2011.
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-0498 Issue 01
Text with Cover No: 23225
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Contents
1 About your gauge . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2
2 The keypad . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4
3 Getting started . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8
4 The display . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10
5 Measurement modes. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13
6 Setting up the gauge . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15
7 Measurement - Taking readings. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 21
8 Measurement options . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 23
9 Measurement - Recording your readings (CG60DL only) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 28
10 Transferring readings to a computer. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 31
11 Storage . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 33
12 Maintenance . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 34
13 Technical specification . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 34
14 Warranty . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 36
15 Spares. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 38
16 Transducers . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 38
17 Condition and preparation of surfaces . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 43
18 Application notes. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 43
19 Sound velocities of common materials. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 46
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hank you for purchasing this Model CG60/Model CG60DL Corrosion Gauge. Welcome to Elcometer NDT.
The Elcometer CG60 and CG60DL Corrosion Gauges are world beating products. With the purchase of this
gauge you now have access to the worldwide service and support network of Elcometer NDT . For more
information visit our website at www.elcometerndt.com.
1 ABOUT YOUR GAUGE
The Model CG60 and CG60DL Corrosion Gauges are handheld gauges for fast and accurate measurement of
material thickness.
The Model CG60 and CG60DL are both 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.
The multi-mode feature of the Model CG60 and CG60DL allows the user to toggle between pulse-echo mode
(standard measurements) and echo-echo mode (eliminate paint or coating thickness).
The Model CG60DL model includes all the features of the Model CG60 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 the Model CG60 and the Model CG60DL.
1.1 STANDARDS
The Model CG60 and CG60DL Corrosion Gauges can be used in accordance with the following Standards and
test methods ASTM E 797, EN 14127 & EN 15317.
T
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1.2 WHAT THIS BOX CONTAINS
Model CG60 Gauge or Model CG60DL Gauge, Bottle of couplant, Battery, 2 x, Carrying case, Test
certificate, Operating instructions, CD with data transfer and data collection software - CG60DL only, RS232
cable and USB to Serial converter CG60DL only
Note: The box does not include a transducer; these must be ordered separately. To order a transducer,
contact Elcometer or your local Elcometer NDT supplier.
Figure 1. Model CG60 and CG60DL Corrosion Gauges
Elcometer 208 DL
Ultrasonic Thickness Gauge
R
CLR
MEM
SEND
MODE
CAL
PRB
0
Data Logger
ON
OFF
CAL
PRB
0
SEND
A
LRM
IN
MM
IN
MM
DUAL
MULTI
SCAN
Elcometer 208
Ultrasonic Thickness Gauge
R
C
A
L
SEND
ALRM
PRB
0
IN
MM
ON
OFF
SCAN
DUAL
MULTI
CLR
MEM
SEND
MODE
CAL
PRB
0
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2 THE KEYPAD
2.0.1 Model CG60 keypad
The ON/OFF key switches the gauge on or off.
To switch the gauge on, press the ON/OFF key. The gauge will perform a brief test by illuminating all of the
segments in the display. After one second, the display will show the internal software version number and
then the measurement mode ‘P-E’ or ‘E-E’. The display then shows ‘0.00’ (or ‘0.000’ if using imperial units),
indicating the gauge is ready to take readings.
To switch the gauge off press the ON/OFF key. The gauge retains all of its settings even when the power is
off. The gauge also features an ‘auto-power down’ function designed to conserve battery life. If the gauge is
idle for 5 minutes, it will switch itself off.
The PRB-0 key sets the gauge to zero in much the same way that a mechanical micrometer is set to zero.
If the gauge is not set to zero correctly, all of the measurements that the gauge makes may be in error by
some fixed value.
See “Setting up the gauge” on page 15.
When the Model CG60 is taking readings, press the CAL key to adjust calibration.
Calibration adjustment sets the sound-velocity value that the gauge uses when calculating thickness. The
gauge will either calculate the sound-velocity from a sample of the material being measured, or allow a known
velocity value to be entered directly. See “Calibration” on page 17.
The IN/MM key toggles between metric (mm) and imperial (inches) units.
This key may be used at any time, whether the gauge is displaying a thickness (MM or IN) or a velocity value
(M/s or IN/µs)
PRB
0
IN
MM
IN
MM
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The UP arrow/SCAN key has two functions.
When the Model CG60 is in CAL or ALARM mode, press this key to increase numeric values on the display.
An auto-repeat function is built in, so that when the key is held down, numeric values increment at an
increasing rate.
When the Model CG60 is taking readings, this key switches SCAN measurement on and off.
See “Measurement options” on page 23.
The DOWN arrow/Backlight key has two functions.
When the Model CG60 is in the CAL or ALARM mode, press this key to decrease numeric values on the
display. An auto-repeat function is built in, so that when the key is held down, numeric values decrease at an
increasing rate.
When the Model CG60 is taking readings, the DOWN arrow key switches the display backlight between three
settings; on, off and auto.
See “Backlight” on page 27.
The ALRM key has two functions.
Hold down the ALRM key when switching on the Model CG60 to switch the audible beeper on or off.
When the Model CG60 is taking readings, press the ALRM key to toggle the alarm on or off, and to allow the
nominal thickness value to be adjusted.
See “Alarm” on page 24.
The DUAL/MULTI key toggles between pulse-echo measurement mode and echo-echo measurement mode.
This enables the user to switch very conveniently between measurement modes depending on application
requirements.
See “Measurement options” on page 23.
The SEND key sends the currently displayed thickness measurement to an external storage device via the
RS232 port.
See “Transferring readings to a computer” on page 31.
DUAL
MULTI
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2.0.2 Model CG60DL keypad
The ON/OFF key switches the gauge on or off.
To switch the gauge on press the ON/OFF key. The gauge will perform a brief test by illuminating all of the
segments in the display. After one second, the display will show the internal software version number, the
current batch location and location status, and then the measurement mode ‘P-E’ or ‘E-E’. The display then
shows ‘0.00’ (or ‘0.000’ if using imperial units), indicating the gauge is ready to take readings.
To switch the gauge off press the ON/OFF key. The gauge retains all of its settings even when the power is
off. The gauge also features an ‘auto-power down’ function designed to conserve battery life. If the gauge is
idle for 5 minutes, it will switch itself off.
The PRB-0 key sets the gauge to zero in much the same way that a mechanical micrometer is set to zero.
If the gauge is not set to zero correctly, all of the measurements that the gauge makes may be in error by
some fixed value.
See “Setting up the gauge” on page 15.
When the Model CG60DL is taking readings, press the CAL key to adjust calibration.
Calibration adjustment sets the sound-velocity value that the gauge uses when calculating thickness. The
gauge will either calculate the sound-velocity from a sample of the material being measured, or allow a known
velocity value to be entered directly.
See “Calibration” on page 17.
When the Model CG60DL is taking readings, press the MODE key to adjust the features and settings of the
gauge (alarm, scan, units, P-E/E-E, backlight, and beeper). The MODE key is used in conjunction with the
arrow and SEND keys to enable/disable the features and settings.
PRB
0
MODE
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The UP arrow key has three functions.
When the gauge is in CAL or ALARM mode, press this key to increase numeric values on the display. An
auto-repeat function is built in, so that when the key is held down, numeric values increment at an increasing
rate. When MODE key has been pressed, the UP arrow key scrolls through the various features and settings
of the gauge.
When the data-logging feature has been activated by pressing the MEM key, pressing the UP arrow key
scrolls through the various files, memory locations, and functions of the data logger.
The DOWN arrow key has three functions.
When the gauge is in the CAL or ALARM mode, press this key to decrease numeric values on the display. An
auto-repeat function is built in, so that when the key is held down, numeric values decrease at an increasing
rate. When MODE key has been pressed, the DOWN arrow key scrolls through the various features and
settings of the gauge.
When the data-logging feature has been activated by pressing the MEM key, pressing the DOWN arrow key
scrolls through the various files, memory locations, and functions of the data logger.
The MEM key enables/disables the data logging feature of the Model CG60DL. This key is used in
conjunction with the UP/DOWN arrows, SEND, and CLR keys. These keys, in combination, control the data
logging features of the Model CG60DL.
See “Measurement options” on page 23.
The CLR key is used with the data-logging feature of the Model CG60DL. This key clears the contents of an
entire batch, or individual memory locations. 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 “Measurement options” on page 23.
The SEND key is used for sending data to internal memory locations, and external peripheral devices (serial
printer or computer). The SEND key is also used to select data logging functions in the Model CG60DL.
MEM
CLR
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3 GETTING STARTED
3.1 FITTING BATTERIES
The Model CG60/CG60DL may be used with dry cell batteries or rechargeable batteries.
2 x LR6 (AA) alkaline batteries are supplied in the kit.
When the battery voltage is low the entire display will start to flash. When
this occurs the batteries should be replaced.
To fit or replace batteries:
1. Locate battery compartment cover (Figure 2) at top of gauge.
2. Unscrew battery compartment cover.
3. Referring to battery polarity instructions on rear of gauge, insert
batteries into gauge ensuring correct polarity.
4. Replace battery compartment cover.
Note: 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.
Elcometer 208 DL
Ultrasonic Thickness Gauge
R
CLR
MEM
SEND
MODE
CAL
PRB
0
Data Logger
ON
OFF
CAL
PRB
0
SEND
A
LRM
IN
MM
IN
MM
DUAL
MULTI
SCAN
Battery
compartment
cover
Figure 2. Fitting batteries
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3.2 CHOOSING THE TRANSDUCER
When you purchased your gauge you should have also purchased a suitable transducer for your
application. If you have not yet done so, refer to “Transducers” on page 38, which will help you identify the
correct transducer type. Alternatively contact Elcometer NDT, your local Elcometer NDT supplier or visit
www.elcometerndt.com.
3.3 FITTING 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 NDT, 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 3. Typical Transducer
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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.
3.4 SWITCHING ON/OFF
To switch on or off, press the on/off key The gauge will switch off automatically after 5 minutes of
inactivity.
4 THE DISPLAY
The display segments for the Model CG60 and the Model CG60DL are
shown in Figure 5.
The following section describes the individual parts of the display and
their meaning.
Wearface
Figure 4. Transducer - bottom view
INMM/ s µ
Figure 5. The LCD Display -
Elcometer CG60 and
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Display segment Information displayed
The numeric portion of the display consists of 4 complete digits preceded by a leading ‘1’,
and is used to display numeric values, as well as occasional simple words which indicate the
status of various settings. When the gauge 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. Only the left-most bar and the underline
will be on when the gauge is idle. Six or seven of the bars should be on when the gauge is
taking a measurement. If fewer than five bars are on, the gauge is having difficulty achieving
a stable measurement, and the thickness value displayed could be in error.
Refer to “Read display” on page 22 and “Transducers” on page 38 for information on how to
achieve a stable measurement.
When the + symbol is on and blinking, this indicates that the Model CG60DL is currently
operating in echo-echo (through-paint/coating) mode.
INMM/ s µ
INMM/ s µ
INMM/ s µ
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When the MM symbol is on, the gauge is displaying a thickness value in millimetres. The
maximum value displayed is 25.40 millimetres (MM).
When the IN symbol is on, the gauge is displaying a thickness value in inches. The
maximum thickness that can be displayed is 1.0000 inches (IN).
When the M symbol is on, in conjunction with the /s symbol, the gauge is displaying a sound-
velocity value in metres-per-second (M/S).
When the IN symbol is on, in conjunction with the /µs symbol, the gauge is displaying a
sound-velocity value in inches-per-microsecond (IN/µS).
Display segment Information displayed
IN / s µ MM
INMM/ s µ
INMM/ s µ
IN / sMM µ
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4.1 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.
5 MEASUREMENT MODES
Your gauge has two measurement modes, Pulse-Echo and Echo-Echo.
5.1 PULSE-ECHO MODE (P-E)
This mode measures from the initial pulse (sometimes referred to as an artificial zero) to the first echo
(reflection). This mode only requires one reflection and it is therefore the most sensitive mode for measuring
weak reflections (flaws) typically found when measuring heavily corroded metals. If this mode is used to
measure a coated sample, then the thickness of the substrate plus coating will be measured.
Note: Rough surface conditions can have an effect on the overall accuracy in this mode. If the surface
condition is in question, the pulse-echo mode should be used in conjunction with performing an off block
automatic zero as the temperature gradient changes.
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5.2 ECHO-ECHO MODE (E-E)
This mode measures between two reflections. This technique is commonly used to eliminate errors from
surface coatings and also to make measurements in multiple layered materials. The disadvantage is that
two echoes are needed which requires a much stronger echo (reflection).
Note: Echo-echo mode cannot be used for flaw or pit detection. Therefore, inspectors may need to use this
mode in conjunction with the standard coating off (pulse-echo) flaw detection mode for some applications.
Chassis tubing inspectors and sanctioning bodies will typically use the echo-echo mode for tubing with
powder coatings, and pulse-echo mode for tubing without coating. This combination of using both modes is
ideal for very detailed inspections.
To select measurement mode:
Selection of measurement mode is now complete.
1. Press ON/OFF key to switch on the gauge.
2. Press DUAL/MULTI key to toggle between the
measurement modes. The gauge will display
P-E or E-E, depending on which mode the
gauge is in.
3. Repeat step 2 until correct mode is displayed.
1. Press ON/OFF key to switch on the gauge.
2. Press MODE key to activate features and
settings. The gauge will display GAtE P-E or
GAtE E-E, depending on which mode the
gauge is in.
3. Press SEND key to toggle between the
measurement modes.
4. Press MODE key when correct mode is
displayed.
Model CG60 Model CG60DL
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6 SETTING UP THE GAUGE
6.1 TRANSDUCER - ZEROING
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.
Though the gauge will remember the last zero point, it is generally a good idea to set the zero 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. The zero probe routine must be done prior to calibration.
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. Press ON/OFF key to 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 face of this disc.
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4. Make sure that the gauge is in P-E (pulse-echo mode):
Note: The Probe-Zero feature is not used in Echo-Echo through-paint mode, and has been disabled. If
the PRB-0 key is pressed, while in this mode, ‘nO’ followed by ‘Prb0’ will be displayed.
4. Press the transducer against the probe-disc, making sure
that the transducer is flat against the surface (Figure 6).
The display should show some thickness value, and nearly
all the bars of the stability indicator should be illuminated.
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.
Figure 6. Transducer pressed against 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 actual measurements.
1. Press DUAL/MULTI key to toggle
measurement mode to P-E. 1. Press MODE key.
2. Press SEND key to toggle measurement
mode to P-E.
3. Press MODE key to confirm selection.
Model CG60 Model CG60DL
Elcometer 208
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Though 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.
6.2 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 the Model CG60 and Model CG60DL gauges:
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: Although the gauge has a through-paint/coating feature, 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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6.2.1 One-point calibration
This procedure requires a sample piece of the material to be measured, the exact thickness of which is
known, e.g. from having been measured by some other means.
1. Press ON/OFF key to switch on the gauge.
1. Set the zero point of the gauge - see “Setting up the gauge” on page 15.
2. Apply couplant to the sample piece.
3. Press the transducer against the sample piece, making sure that the transducer is flat against the
surface of the sample. The display should show some (probably incorrect) thickness value, and nearly
all the bars of the stability indicator should be illuminated.
4. Having achieved a stable reading, remove the transducer.
If the displayed thickness changes from the value shown while the transducer was coupled, repeat
step 3 and 4.
5. Press the CAL key. The MM (or IN) symbol should begin flashing.
6. Use the UP and DOWN arrow keys to adjust the displayed thickness up or down, until it matches the
known thickness of the sample piece.
7. Press the CAL key again. The M/s (or IN/µs) symbols should begin flashing. The gauge is now
displaying the sound-velocity value it has calculated.
8. Press the CAL key once more to exit the calibration mode.
The gauge is now ready to perform measurements.
CG60_CG60DL_TMA_0498_00_01_23225_A6L.fm Page 18 Tuesday, November 22, 2011 12:19 PM