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1. KRATKI VODI^ ZA KORI[]ENJE DODIRNOG VLAGOMERA
1. QUICK REFERENCE GUIDE
1. Turning the meter ON
ON
OFF
- Press the button
briefly to turn it on
- Model of the meter and battery status is shown
- After autocalibration is completed, device starts
to display measured MC (in %)
' ' '
MC
00%
.
PAR
ON
OFF
4
5. Measurement - ALARM function
- In case that measured MC is higher than certain
setpoint, alarm will be triggered
- Device will inform the user with sound alarm and
blinking display that measured MC is too high
' ' ' ' '
MC
432%
.
PAR
ON
OFF
6
3. DESCRIPTION OF MOISTURE METER
' ' ' ' '
MC
126%
.
3
1
PAR
ON
OFF
WOOD MOISTURE METER
DVD-241
4
2
DVD-241/MCD-50/DVD-340
DVD-241/MCD-50
8
4. TURNING METER ON / OFF AND AUTOCALIBRATION
Turning the meter ON is performed with brief pressing on the button
will briefly display model and then battery status. During this time, device will automatically perform
AUTOCALIBRATION procedure, i.e. series of test-measurements required for its adaptation to current
operating conditions (ambient temperature, air humidity, etc).
It is essentially important to ensure that meter during autocalibration has such position that contact
plate hangs free in the air, i.e. there is nothing behind contact plate blocking it!
Do not hold fingers or other objects behind contact plate during
autocalibration. Existence of any object near contact plate during
autocalibration procedure can corrupt this process and results in
inaccurate measurement and measuring errors.
After a few seconds, when autocalibration procedure is finished, meter
MC
0
0%
will display:
.
,
which signals that it is ready for measurement
or other adjustments.
10
5. DEVICE SET-UP AND ADJUSTMENT FOR MEASUREMENT
5.1
WOOD DENSITY parameter setting
Information regarding type of wood for MC measurement is given via WOOD DENSITY for that type of
wood. That is why it is required to determine wood density in t/
is most commonly given as a table data for specific wood type (specie) when it is absolutely dry.
Data regarding wood density of specific wood specie can be found in appendix of this manual, but
other reliable sources can also be used. Portable moisture meters DVD-241, DVD-340 and MCD-50
support selection of WOOD DENSITY in range 0.20 t/
Wood density adjustment is performed in following way:
- Meter must be in basic measurement mode (
PAR
- Press the button
once (see image)
- Use buttons
and
to set wood density (in t/
PAR
- Press the button
to advance to next parameter setting
(wood thickness)
5.3 Additional settings
12
There are several additional settings which are available at separate menu. To access this menu, device
must be in basic measurement mode. Press and hold button
PAR
(see image). Use button
to list the items in menu and buttons
of selected parameter. Battery status is shown first (
T)
25ªC
(
). These are informational data which can not be changed.
Following parameters are changeable:
- Value of moisture content that will trigger
signal and blinking of the display will warn the user that MC is too high.
It provides easy detection the sample that has MC significantly above others.
Alarm function is turned OFF when value of this parameter is set to
It can be set in range from 4 to 99.9%.
TO) 2min
- Turn off time (
). It is possible to set the value of this
parameter in range 1 to 60 minutes. Device will turn off automatically
if it is idle for the time defined by this parameter.
CONTRAST
- Display contrast (
). In case that device is used in the
field at high or low temperature, readability of the display can be
low so user can adjust the value of this parameter to improve it.
Proper placing of the meter on the surface of wooden sample means following:
14
- Longer side of contact plate must be parallel to wood fibers when DVD-241 and MCD-50 are used
- Wooden sample must be wider than contact plate and entire surface of contact plate must be laid on
wooden sample. To check MC in narrow wooden samples, use DVD-340.
- Contact plates of DVD-340 must be perpendicular to wood fibers when DVD-340 is used
DVD-241/MCD-50
6.2
Veneer MC measurement procedure
16
Veneer MC measurement is very specific, so it is required to perform following preparation:
- Precisely determine sample thickness. Thickness parameter has great influence for thin samples.
- Place veneer sample on expanded polystyrene layer at least 50 mm thick (polystyrene does not
influence measurement!).
Veneer
NOTES:
- Use only models DVD-241 and DVD-340 to measure MC in veneer.
- Model MCD-50 is not suitable for veneer MC measurement!
- It is more accurate to measure MC of multiple veneer layers (at least 3) while setting total thickness.
- In case veneer is already stacked, set the thickness to 40 mm (best avoid this kind of measurement)
18
7.1 Reset to factory calibration
After entering calibration menu, subsequent pressing on button
like on image bellow, which marks entering the procedure for calibration reset to factory default.
This procedure should be used in case that readings on the meter are not accurate because a user
performed user calibration earlier. It can be also done in case you are not certain wether user
calibration has been performed or not.
To reset the meter, use buttons
and
PAR
OK
the value (
) then press button
to confirm reset to factory
default calibration.
20
8. APPENDIX
8.1 Appendix 1: Additional information regarding wood density and wood moisture content
Wood density is given for wood specie (type) in absolutely dry condition and is expressed in t/
3
g/c
m
. It is calculated as weight of absolutely dry wooden sample divided by its volume.
This density is often given as constant value for specific wood type from specific climate and it
represents important data for wood moisture content measurement.
Wood moisture content for a given sample of wood is defined as the weight of water in wood expressed
as a percentage of the weight of wood fibrous material (which is the weight of the absolutely dry
sample). The moisture content is calculated by the following equation:
u (%) = (m - m ) / m x100
u
o
o
where:
u (%) - equals wood moisture content (MC)
m - equals weight of wet sample
u
m - equals weight of absolutely dry sample
o
i.e., wood moisture content (MC) in wooden sample equals weight of existent moisture content in
sample divided with weight of absolutely dry (same) sample and multiplied by 100.
22
3
DENSITY (t/m )
WOOD SPECIE
min
average
Ivory Wood, Pink
0.8
Jelutong
0.45
Juniper
0.3
0.4
Kapur
0.75
Kekatong
0.82
Kempass
0.72
Keranji
0.80
Keruing
0.78
Kranji
0.75
Kulim
0.78
Larch
0.4
0.5
Laurel, Chilean
0.45
0.48
Linden (Lime)
0.32
0.45
Magnolia
0.5
24
DVD-241 / DVD-340 / MCD-50
Nondestructive hand held MC meter
NIGOS-elektronik
Borislava Nikolica - Serjoze 12, 18000 Nis, Serbia
Tel/fax: +381 18 / 211-212, 217-468
Internet: http://www.nigos.rs
E-mail: office@nigos.rs
2.
Wood density adjustment
PAR
- Press once the button
briefly
-
Use buttons
and
to adjust wood
3
density (given in t/
m
)
' ' '
065 t/m3
.
PAR
ON
OFF
6.
Turning the meter OFF
-
To turn the meter off, press the button
- Device will turn off automatically after selected
idle time
' ' ' ' '
MC
118%
.
PAR
ON
OFF
5
6
7
DVD-340
ON
OFF
.
Upon power-up, device
' ' ' '
MC
3
m
as precisely as possible. Wood density
3
3
m
to 1.10 t/
m
.
' ' '
065 t/m3
.
MC
%
)
3
m
)
and then briefly press button
and
to adjust the value
BAT) 96%
) followed by measured temperature
AL) 30
0%
alarm
(
.
). Sound
' ' '
BAT) 96%
OFF
.
1
' ' ' ' '
MC
126%
.
DVD-340
Polystyrene
PAR
will lead to next item (
to select
' ' '
C-RESET
DENSITY (t/m )
WOOD SPECIE
max
min
average
Mahogany, African
0.41
0.5
Mahogany, Sapelli
0.65
0.64
Mahogany, White
0.45
Mahogany, Philippines
0.55
Mango Wood
0.55
Maple
0.48
0.6
Meranti, Dark Red
0.4
0.6
Meranti, Light Red
0.54
Meranti, White
0.58
Merawan
0.70
0.82
Merbau
0.85
0.5
Niangon
0.6
0.56
Nyatoh (Balam)
0.65
Oak, European
0.39
0.65
3. Wood thickness adjustment
PAR
(see image)
-
Press again
, then use
adjust wood thickness (given in mm)
- Dots in the upper part of display also provide
thickness information (1 dot per each 5mm)
' ' ' ' '
250 mm
.
PAR
OFF
2.
TECHNICAL SPECIFICATION OF MOISTURE METERS
GENERAL CHARACTERISTICS
Power supply
ON
OFF
Consumption
Continuous operating time
Display
Operating conditions
Storage
Device dimensions (W x H x D)
Sensor dimensions (W x H)
Weight
MEASUREMENT
Measurement resolution
Wood MC measurement range
Wood thickness range
Wood density range
DEVICE
FRONT SIDE LAYOUT
1. L
CD DISPLAY displays
:
- Measured moisture content
- Parameter values during set-up
- Messages for user
2. Buttons UP and DOWN are used for increase
or decrease of value of selected parameter
3. Button PAR is used for parameter selection
4. Power ON / OFF button
DEVICE BACK SIDE LAYOUT
5/6. CONTACT PLATE measures moisture
content when pressed against smooth
wood surface
7. Battery compartment
Autocalibration procedure is performed each time the meter is powered ON, which ensures reliability
of measurement in all declared conditions.
If there is any doubt in either measuring accuracy or possible error in autocalibration as a cause of false
measurement, autocalibration should be repeated by simple turning off and turning on the meter again.
Turning meter OFF is performed with short pressing on the button
When it is turned off, the meter does not consume energy from the
battery
.
Device will turn off automatically after selected idle time.
00%
.
PAR
ON
OFF
5.2
WOOD THICKNESS parameter setting
Second essential parameter for correct moisture content measurement is thickness of the wooden sample.
Measured MC value greatly depends on this parameter (especially when thin samples are used - thinner
than 15 mm), so it is required to determine the thickness as precise as possible. Value is entered in mm and
in range 2 to 40 mm for meters DVD-241 and DVD-340 while MCD-50 have range from 10 to 50 mm.
Thickness parameter setting is performed similar to wood density parameter setting:
PAR
- Press the button
again (see image)
- Use buttons
and
PAR
- Press the button
to return to basic measurement mode
MC
%
(display shows
)
After these procedures, all needed parameters are loaded in
PAR
meter's memory. Once entered, these parameters remain stored
in the memory and they are active until next adjustment. In case
ON
there is no need to change these parameters frequently, it is
OFF
enough just to check these values before each measurement
and proceed with measurement immediately.
6.
WOOD MOISTURE CONTENT MEASUREMENT
Wood moisture content measurement is main purpose of this device. Moisture content value (MC) is given
in percentage (%) and displayed on LC display.
PAR
Measurement process itself is very simple procedure and comes to (aside previously described adjustment)
proper placing of the meter on the surface of wooden sample and reading of displayed value.
Complete procedure is as follows:
- Turn the meter on before taking the measurement. Wait until autocalibration is finished and meter is ready
(see chapter 4).
- Check the value of parameters that are adjustable (THICKNESS and DENSITY) and if necessary change
their values to correct ones
- Place contact plates on wood sample and ensure proper position, gently press the device against the
sample and read the measured value
PAR
2
It is recommended to check moisture of the sample at several points in case that conditions allow it in
ON
order to achieve better information about moisture content and its distribution in the wooden sample.
OFF
Turn the meter off after use in order to preserve battery.
6.1
Timber MC measurement procedure
For accurate MC measurement in timber boards the attention must be payed to:
- Moisture distribution along depth of the board should be uniform (board surface must not be overdried
due to exposure to direct sun light or during extensive drying. If necessary, cut the sample in half.
- Place the board (sample) on wooden bars to avoid the influence of the ground on the measurement. Thick
piece of polystyrene (styropor) can be used instead of bars.
7. USER CALIBRATION OF DEVICE AND RESET TO FACTORY CALIBRATION
In case that, for any reason, there is a reason to doubt accuracy of measurement, user can perform
its calibration according at its sole discretion. It is possible to reset the meter to its factory calibration at
any given time.
Main goal of user calibration is that the user himself adjust device reading to match MC of the known wood
sample by changing gain factor (calibration parameter
CALIBRATION MENU ENTERING:
- Device must be in basic MC measurement mode (
- Press and hold button
and then simultaneously press and hold
PAR
for 5 seconds button
i.e. until display shows software version
(see image).
PAR
- Press again button
to see the date of software installation.
7.2 User calibration of the meter
C-RESET
),
Next item in the calibration menu is user calibration. Display will show label (
C-GAIN
After item
is selected, meter must be placed on wood sample with known MC while taking care
that all recommendation for accurate measurement are applied.
Use buttons
and
to change the values of calibration parameters of
GAIN)170
for example: (
). One second after last press on any button, the meter will switch to display of
measured value, for example: (
Calibration procedure consists of successive change of the parameter
GAIN
and verification of reading until wanted value is achieved.
PAR
Press the button
to accept the current calibration value as final.
In case we want to exit further calibration without making any change
of calibration, press the button
PAR
We emphasize that special attention must be paid when this
procedure is used and that user use it at his own risk!
ON
In case that in any time user suspects that meter is making false
OFF
measurement due to user calibration, it is required to reset the device
to factory calibration defaults as described in chapter 7.1.
8.2 Appendix 2: Wood density table
DENSITY (t/m )
WOOD SPECIE
min
3
m
or
Abachi (Samba)
0.25
Abura
Acacia
0.6
Afara, White
Afrormosia
Agathis
Alder
0.45
Ash
0.41
Atlas
0.6
Balau
Balsa
Beech
0.49
Beech, Chilean
Bintangor
3
DENSITY (t/m )
WOOD SPECIE
max
min
0.9
Okume
0.31
Olive Tree
Padauk
Palisander
Pear
0.55
0.75
Perupok
0.63
Pine
0.38
Pine, White, Yellow
Plum
Poplar
0.36
Pulai
Punak
Pyinkado
0.93
Ramin
TABLE OF CONTENTS
1.
QUICK REFERENCE GUIDE ..............................................................................................................
2. TECHNICAL SPECIFICATION OF MOISTURE METERS DVD-241/DVD-340/MCD-50
3. DESCRIPTION OF MOISTURE METER
4. TURNING METER ON / OFF AND AUTOCALIBRATION PROCEDURE
5. DEVICE SET-UP AND ADJUSTMENT FOR MEASUREMENT
5.1 WOOD DENSITY parameter setting
5.2 WOOD THICKNESS parameter setting
5.3 Additional settings
............................................................................................................. 12
6. WOOD MOISTURE CONTENT MEASUREMENT
6.1 Timber MC measurement procedure
6.2 Veneer MC measurement procedure
7. USER CALIBRATION OF DEVICE AND RESET TO FACTORY CALIBRATION
7.1 Reset to factory calibration
7.2 User calibration of the meter
8. APPENDIX
.................................................................................................................................... 20
8.1 Appendix 1: Additional information regarding wood density and wood MC
8.2 Appendix 2: Wood density table
4.
Measurement
-
Gently press contact plate on the flat, smooth
and
to
surface of the wood sample
- Read the measured value on display (in %MC)
- Repeat the measurement in several points
' ' ' ' '
MC
MAX
HOLD
ON
DVD-241/DVD-340/MCD-50
Battery 9V, alkaline or rechargeable
3mA (DVD-241/340), 6mA (MCD-50)
up to 200h (DVD-241/340), up to 100h (MCD-50)
LCD, digital
0
T: 5
¸
50 C; RH: 5 ¸ 90%
0
T: - 40 ¸ 85 C; RH: 5 ¸ 90%
(
60 x 120 x 28 (DVD-241/MCD-50); (60 x 150 x 28 (DVD-340) (mm)
)
(48 x 75)
(mm) (DVD-241/MCD-50)
140 g
0.1%
(DVD-241/340); 0.5% (MCD-50)
(0 ¸ 100) %
( ) (values above 30% should be considered informative!)
2 ¸ 30
(DVD-241/340);
10 ¸ 50
(MCD-50) (mm)
3
(
0.20 ¸ 1.10) (t/m )
Contact MC meters DVD-241, DVD-340 and MCD-50
are made for quick reading of wood moisture by simple
pressing on flat wooden surface (nondestructive).
There is specially designed contact plate on back side
of DVD-241 and MCD-50 that the meter use to read MC
in the sample when it is pressed against it. DVD-340 use
three contact plates at the front part for this purpose.
- DVD-241 is suitable for fast checking of MC in stack
- DVD-340 is suitable for hard to access samples and
small dimension samples
- MCD-50 is suitable for on-field MC check in rough
samples. It is least sensitive to surface moisture.
Although MC meters measure full range of moisture
content (0-100%), only MC up to 30% is considered
to be accurate.
MC values above 30% are approximate and only show
that wood sample is wet (contains free water).
ON
OFF
.
to set wood thickness (in mm)
' ' ' ' '
GAIN
- will be discussed more in chapter 7.2)
' ' '
' ' '
MC
0
0%
.
).
1
C-GAIN
CAL) 13.5%
).
' ' '
ON
OFF
to exit this procedure.
3
WOOD SPECIE
average
max
min
0.35
0.52
Birch
0.46
0.5
Camphorwood
0.5
0.65
0.75
Cedar
0.35
Cherry
0.52
0.45
0.65
Chestnut
0.4
0.45
Cypress
0.6
Daru Daru
0.4
0.65
0.82
Durian
0.85
Ebony
0.7
0.75
Elm
0.52
0.85
0.2
Fir, Silver, Douglas
0.32
0.88
Hickory
0.66
0.65
Hornbeam
0.45
Iroko
0.60
3
WOOD SPECIE
average
max
min
0.4
0.57
Rosewood
Rubberwood
0.75
0.7
Seminai
0.7
Sequoia
0.76
Seraya
0.65
0.50
Spruce
0.48
Teak
0.45
Teak, Rhodesian
0.35
0.7
Ulin
0.56
Walnut, African
0.4
Walnut, European
0.45
0.45
Willow, White
0.72
Yew
0.61
0.82
Zebrano
0.52
................................................................................................. 6
..................................................... 8
................................................................... 10
..................................................................................... 10
................................................................................. 11
................................................................................... 13
................................................................................ 15
................................................................................ 16
............................................ 17
............................................................................................... 18
............................................................................................. 19
....................................................................................... 21
3
3
126%
.
PAR
ON
OFF
5
)
7
9
PAR
ON
OFF
11
250 mm
.
PAR
ON
OFF
13
15
17
SW)
223
.
PAR
2
ON
OFF
19
).
C-GAIN
. Display will show
C-GAIN
PAR
ON
OFF
21
3
DENSITY (t/m )
average
max
0.6
0.8
0.55
0.6
0.45
0.55
0.62
0.55
0.5
0.55
0.4
0.90
0.60
1.0
0.85
0.64
0.6
0.45
0.71
0.8
0.7
0.8
0.6
23
3
DENSITY (t/m )
average
max
0.80
0.55
0.95
0.35
0.50
0.40
0.60
0.8
0.95
0.45
0.75
0.65
0.4
0.74
0.65
0.65
1
2
.............................. 5
.................... 20
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