TRAMEX CMEX II User manual

user guide
CMEX II
concrete moisture
meter (Digital)
04/2015

USER GUIDE
3
TABLE OF CONTENTS
Introduction.......................................................................4
Howitworks...................................................................5-6
Instrument Features........................................................7-8
Operating Instructions.......................................................9
Non-Destructive Measurement Mode .......................10-15
Concrete Scale.............................................................10
CM (Carbide Method) Equivalent Scale......................11
Gypsum Scale..............................................................11
REF(Reference)Scale..................................................11
Calibration .................................................................12
CMEX II Displays.......................................................13
Drying time for concrete oors and screeds............13-14
Testing moisture content in a oor slab.......................14
Pre-testing guidelines..................................................14
Guideline test procedures as per ASTM F2659...........15
Humidity Measurement Mode ..................................16-25
Relative Humidity Measurement................................17
Moisture Testing Guidelines...................................17-23
Hole Liner Instructions ASTM F2170 / BS8201,
8203, 5325...........................................................20-21
Calibration Check Salts..........................................24-25
Wood Pin Meter Mode...............................................26-43
Factors Affecting Moisture Readings..........................27
Wood Flooring ......................................................28-29
Temperature Adjustment Chart..................................30
Humidity and Moisture Content Relationship.............31
Species Correction Charts......................................32-43
Limitations .......................................................................44
Calibration ......................................................................44
Warranty ............................................................................45
Product Development......................................................46
Safety...............................................................................46

USER GUIDE
4
INTRODUCTION
Thank you for selecting the new CMEXpert II instrument,
from Tramex. It has 3 measurement modes.
1. Non-invasive, Non-destructive test (NDT) mode
The CMEXpert II utilises “state of the art”
electronic technology to provide you with an
accurate and easy to use non-invasive instrument
for non-destructive testing (NDT) of Moisture
Content (MC%) in concrete and comparative
readings in gypsum and other oor screeds.
2. Hygro-i probe mode
This enables the CMEXpert II to measure
relative humidity (RH), temperature, dew point
temperature and mixing ratio of the environment
or in a structural material. A structural material
such as a concrete slab can be tested using the in-
situ method (ASTM F2170) or RH Hood methods
(British Standards BS 8201, 8203, 5325).
3. PIN Probe mode
This enables the CMEXpert II to measure the
percentage moisture content (MC%) of wood. The
CMEXpert II can also be used for wood-based
products.

USER GUIDE
5
HOW IT WORKS
In concrete moisture measurement NDT mode, the
instrument operates on the principle that the electrical
impedance of a material varies with its moisture content.
The electrical impedance is measured by creating a
low frequency alternating electric eld between the
electrodes as illustrated in Figure 1.
The instrument is pressed onto the material surface
with the pins fully compressed to measure/detect the
moisture content.
Figure 1

USER GUIDE
6
This eld penetrates the material under test. The very
small alternating current owing through the eld is
inversely proportional to the impedance of the material.
The instrument detects this current, determines its
amplitude and thus derives the moisture value.
In Hygro-i probe mode, the CMEXpert II determines
the capacitance of the RH probe sensor which varies
with the relative humidity of the testing environment.
The CMEXpert II displays this capacitance as percentage
relative humidity (%RH). It also measures temperature
and displays dew-point temperature and mixing ratio.
In Pin probe mode the CMEXpert II is a resistance-type
pin-meter for determining the moisture content of wood
and wood-based products.

USER GUIDE
7
INSTRUMENT FEATURES
Your CMEXpert II employs advanced digital technology
to enable the incorporation of the many features listed
below.
●3 modes of measurement: Non-destructive moisture
measurement, hygrometer and wood pin probe.
●6 simple membrane keypad controls:
ON/OFF
SCALE
UP
DOWN
HOLD / AUDIO
BACKLIGHT
●Moisture readings and scale are displayed on a
clear easy to read liquid crystal display (LCD).
●4 NDT Scales: Concrete, CM Equiv (Carbide
Method equivalent for concrete), Gypsum and a
Ref (Reference) scale. These are selected using the
key and the or keys.
●Wood pin probe mode is selected by using the
key.
●Relative Humidity (RH) readings, probe
temperature, dew point temperature and mixing
ratio are automatically displayed when the
Hygro-i Probe is plugged into the CMEXpert II
(Hygrometer Mode).

USER GUIDE
8
●To conserve battery life, the instrument automatically
powers OFF after 10 minutes of inactivity or when
the key is pressed. If a key is pressed the
power off time will be extended for an additional ten
minutes.
●Backlit display allows the display to be easily read
in poor light conditions. This is enabled by pressing
the key. The backlight stays on for a period of
time set.
●Backlight display time. To adjust the backlight
display time, press the and keys together.
Then scroll with the key from 10 – 60 seconds.
(If the key is pressed, you will enter language
choice settings.) When time is chosen select
key to conrm and return to scale mode. (Longer
backlight timeouts will reduce the battery life.)
●Language display adjustment. To adjust the language
display, press the and keys together. Then
scroll with the key through the language library.
(If the key is pressed, you will enter the backlight
time settings.) When language is chosen select
key to conrm and return to scale mode.
●HOLD freezes reading to facilitate ease of
recording readings. When the CMEXpert II is in
HOLD mode, ‘H’ will ash on the display. If HOLD
was selected prior to the CMEXpert II automatically
powering off, the frozen display reading is digitally
memorized and restored next time ON is selected.
●When the battery requires replacement a LOW
BATTERY message is shown on the LCD.

USER GUIDE
9
OPERATING INSTRUCTIONS
1 = Phono socket for Wood Probes.
2 = Hygro-i Probe Socket (automatic hygrometer mode when
plugged in).
3 = Backlit display.
4 = Hold Key
5 = Scale Key.
6 = UP / DOWN Keys
7 = ON / OFF Key 10 minute switch off
8 = Light Key.
Figure 2
The instrument face with brief notes on the push button
controls and LCD is shown below.

USER GUIDE
10
NON-DESTRUCTIVE MEASUREMENT MODE
1. Press the key to power up. With no Hygro-i
probe or pin probe connected the last used scale
will be displayed on the LCD. Press key again
to power off.
2. To change mode, press key to select the Concrete,
Pin Probe or the comparative material scales. The
comparative material scales consist of CM Equiv.,
Gypsum and Ref. Select the CM Equiv., Gypsum or
Ref. scale using the key or key.
3. Press your CMEXpert II directly onto the surface
of the material being tested ensuring that all the
electrode spring-loaded pins are fully compressed.
Concrete Scale
When the Concrete scale is selected the moisture content
(MC) is shown on the right-hand side of the bottom line of
the display. The moisture content (MC) is displayed 0 to
6.9% on the CMEXpert II display. Readings on a concrete
oor slab obtained on this scale indicate moisture content
and should not be confused with Pounds (lbs) emission or
any other unit of measurement obtained by other moisture
testing methods or meters. It should also be noted that
there seems to be no linear correlation between moisture
content measurements and lbs emission measurements as
obtained using calcium chloride testing methods.

USER GUIDE
11
CM Equivalent Scale (for concrete)
The CMEXpert II gives readings of 0 to 4.3 on the CM
Equivalent Scale. These are approximated equivalent
readings to the carbide test method for concrete.
Gypsum Scale
The CMEXpert II gives moisture content readings from 0
to 12 (comparative) on Gypsum and Anhydrite screeds.
REF Scale
For the Reference scale the readings are comparative
from 0 to 99. A visual indication is also given by the bar
display on the bottom line of the LCD.
The readings on the reference scale are not to be interpreted
as a measurement of percentage moisture content (%MC)
or relative humidity (RH). It is not a relative humidity
reading and it does not have any linear correlation with
Relative Humidity measurements. This scale should
be regarded as a comparative or qualitative scale only.
This reference scale is included to facilitate comparative
testing of different areas where direct contact with the bare
concrete surfaces may not be possible due to some form of
very thin coating or covering on the concrete, or additive
in the concrete that could inuence the readings. This scale
is not suitable for reading through thicker oor coverings
such as wood laminates etc. Readings from the reference
scale are comparative only and of help in identifying areas
with moisture problems.

USER GUIDE
12
Calibration
For regular on-site assessment of your CMEXpert II in
moisture measurement mode, a calibration-check plate is
available from the suppliers of your CMEXpert II. Should
it be found that readings are outside the set tolerances, it
is recommended that the CMEXpert II be returned for re-
calibration. Calibration adjustments should not be carried
out by anyone other than Tramex or their authorized
service provider who will issue a calibration certicate on
completion.
Requirements for quality management and validation
procedures, such as ISO 9000 and National Standards,
have increased the need for regulation and verication
of measuring and test instruments. It is therefore
recommended that calibration of the CMEXpert II should
be checked and certied in accordance with the standards
and/or protocols laid down by your industry (usually on
an annual basis) by an authorised test provider. The name
of your nearest test provider and estimate of costs are
available on request.

USER GUIDE
13
Typical CMEXpert II Displays
Drying time for concrete oors and screeds
Concrete oors and screeds must be allowed to dry to an
adequate level before the installation of sheet material,
tile, wood or coating. Manufacturers of such systems
generally require moisture testing to be performed before
installation on a oor slab. Moisture content measurement
is one such method. Excessive moisture in or permeating
from a oor covering or coating can cause failures such
as condensation, blistering, delaminating, movement and
general deterioration of the nished ooring/coating.
There is also a risk of promoting microbial growth. No
exact period can be specied for the drying of such oors
to reach acceptable moisture content, as this is affected by
temperature and humidity within the building as well as
concrete curing times and other factors. Typically a period
of 1 month per inch (25mm) depth of concrete or sand/
cement screed is often quoted. Longer periods may be
required in areas of high humidity or low temperature.

USER GUIDE
14
During the drying period and prior to applying the oor
covering, the oor should be regularly checked to monitor
moisture content.
Testing for moisture content in a oor slab
Pre-test conditioning and preparation
For best and most accurate results, tests should be carried
out after the internal conditions of the building in which
the slab is located have been at normal service temperature
and humidity for at least 48 hours. All articial heating or
drying equipment should be turned off at least 96 hours
before nal readings are attempted, otherwise results may
not accurately reect the amount of moisture present or
moisture movement in the slab during normal operating
conditions. Prior to testing, the actual test area should be
clean and free of foreign substances.
Pre-testing guidelines
Where covered oor slabs are being tested, all covering
materials, adhesive residue, curing compounds, sealers,
paints, etc., shall be removed to expose a test area of clean
bare concrete. For removal of any existing ooring or
adhesives, strictly observe all the appropriate safety and
health practices relevant to cleaning and removal of these
types of materials. Removal of covering materials and
cleaning, if required, should take place a minimum of 48
hours prior to testing. Use of water based cleaning methods
that could lead to elevated surface and/or sub-surface
moisture levels in the oor slab are not recommended, and
the testing after such treatment could result in elevated
readings. No visible water in liquid form should be present
on the concrete at the time of testing. Avoid testing in
locations subject to direct sunlight or sources of heat. Use
of articial aids for accelerated drying of concrete is not
recommended. If they are being used it is recommended
they should be turned off at least four days before taking
nal readings.

USER GUIDE
15
Guideline test procedures as per ASTM F2659
1. Remove any dust or foreign matter from the
CMEXpert II electrodes before commencing tests.
Make sure that the oor slab being tested is clean and
bare and free from dust, dirt or standing water.
2. Push the ON button and press the instrument directly
onto the surface of the material being tested ensuring
that all of the electrode spring loaded pins are fully
compressed. Read the moisture measurement from
the appropriate scale of the display.
3. On a rough surface, take a number of readings in
close proximity to one another such as 3 to 5 readings
within an area of 1 ft2(929cm2) at each location. If
the readings vary, always use the one with the highest
value.
4. Perform at least eight tests for the rst 1000ft2
(100m2) and at least ve additional tests for each
additional 1000ft2(100m2). Include test locations in
the centre of the oor and within 3ft (1m) of each
exterior wall.

USER GUIDE
16
HUMIDITY MEASUREMENT MODE
The Hygro-i Probe utilises state of the art electronic
technology to provide an "easy to use" and accurate method
for measuring relative humidity, mixing ratio, temperature
and dew point in a wide range of applications such as:
●Heating, ventilation and air conditioning (HVAC)
systems.
●Environmental and building monitoring.
●Building inspection.
●Flooring (including in-situ method as per ASTM
F2170 and the in-situ and hood methods as per
British Standards BS 8201, 8203, 5325.)
A typical CMEXpert II display with the Hygro-i Probe is
shown below. When the Hygro-i Probe is plugged into the
CMEXpert II, the or key can be used for changing
the temperature between ˚C and ˚F and the mixing ratio
between g/kg and grains/lb.
Flashing "H" in Hold mode
Relative Humidity T˚C
Mixing Ratio g/kg
Dew-piont (Td)˚C
IMPERIAL

USER GUIDE
17
RELATIVE HUMIDITY MEASUREMENT
There are two International Standard methods of relative
humidity measurement in ooring that can be carried out
with the CMEXpert II with the Hygro-i probe attached:
(a) In-situ (below the surface of the slab) ASTM F2170
and BS 8201, 8203, 5325.
(b) RH Hood (on the surface of the oor slab) BS 8201,
8203, 5325.
(a) In-situ Relative Humidity Test Method – ASTM
F2170 Guidelines.
Perform 3 per 1000ft2(100m2) and 1 per next 1000ft2
Holes must be drilled dry and perpendicular (90˚), do not
use water for cooling or lubrication.
When drying is from the top only, it is recommended
that the hole should be drilled to approx 40% of the slab
thickness.
When drying is from both sides, it is recommended that
the slab should be drilled to approx 20% of slab thickness.
A hole cleaning brush is often required to ensure the drilled
hole is free from any loose particles. A vacuum should also
be used to ensure the drilled hole is free from any dust.
The user should always refer to ASTM or national
standard guideliness for denitive and current procedure
and specications.

USER GUIDE
18
MOISTURE TESTING GUIDELINES
When performing moisture testing of concrete it is
important to get the most accurate and most useful data
from the tests. For this reason Tramex recommend a
two-pronged approach. The rst step is to carry out a
non-invasive moisture test with the Tramex CME4 or
CMEX. This measures the top section of the concrete
slab and gives an average percentage moisture content of
the footprint area of the meter. These readings should be
used to determine where and how in-situ relative humidity
(RH) testing is performed. If the CME4 / CMEX reading
is above 5%, Tramex recommend that the test holes are
drilled, sleeves are placed and capped and left for a period
of 72 hours. The probes are then inserted. A suitable
equilibration time is allowed before taking readings (see
below). If the CME4 / CMEX reading is at or below 5%,
the testing can be carried out either by placing sleeves and
leaving 72 hours as above or inserting probes immediately
after sleeves have been placed and taking readings after
72 hours.
The above recommendations are based on the requirements
to prolong the life of the RH probe and to increase the
accuracy of the test. Tramex recommend that the RH
probes are not left in-situ for prolonged periods of time
when RH values are above 93%. With the Tramex system
it is possible to remove the probe and seal the sleeve for
future testing, thus giving a more reliable and accurate test.

USER GUIDE
19
Equalibration Time:
Allow at least 30 minutes for probe to reach
temperature equilibrium before measuring relative
humidity. It is vitally important that the concrete is
at the same temperature as the probe.
Even a slight difference in temperature will produce
a signicant error in relative humidity measurement.
Check that meter readings do not drift by more than
1% RH over a 5 minute period.
The sensor in the Hygro-i probe may take longer to
recover if exposed to readings above 93% and can be
damaged by prolonged exposure to high humidity.

USER GUIDE
20
HOLE LINER INSTRUCTION ASTM F2170