User Guide

Moisture Meter

Model MO220

Introduction

Congratulations on your purchase of the Extech MO220 Moisture Meter. This instrument is a conductivity moisture meter specifically designed for the wood industry.

The instrument has eight calibration scales, enabling the user to take accurate moisture measurements in 170 wood species. Moisture measurements can be taken using the integral pin electrodes, or using the heavy duty moisture probe.

When used with the temperature probe, the moisture measurements are automatically corrected with respect to temperature. This meter is shipped fully tested and calibrated and, with proper use, will provide years of reliable service.

2 MO220 V1..2 4/10

Specifications

Display

Measurement principle

Range

Electrode length

Dual measurement scale LCD with bargraph metering

Electrical resistance

Wood: 6 to 44%

0.3” (8mm)

Electrode pins

Auto Power OFF

Integrated, replaceable

After approx. 15 minutes

Power supply Two (2) ‘AAA’ 1’5V batteries

Meter housing Impact-proof plastic

Operating Temperature 32 to 104 o

F (0 to 40 o

C)

Operating Humidity

Dimensions

85% Relative Humidity maximum

5.1 x 1.6 x 1.0” (130 x 40 x 25mm)

Description

Meter Description

2. Low battery icon

3. LCD measurement reading

1

5. Units of measure

6. External moisture sensor input

7. Remote temperature probe jack

8. Temperature units button

9. Wood group letter selector button

10. Power ON-OFF button

Note that the battery compartment is located on the rear of the instrument.

2

3

4

8

9

5

6

7

10

3 MO220 V1..2 4/10

Operation

CAUTION: The electrode measurement pins are extremely sharp. Use care when handling this instrument. Cover the pins with the protective cap when the instrument is not in use.

Basic Measurement Instructions

1. Remove the cap to expose the needle electrodes OR connect the heavy duty moisture probe socket on the right hand side of this instrument

2. Switch the meter ON by pressing the button.

3. Select the appropriate wood calibration scale A, B, C, E, F, G, H or J (see the Wood

Calibration Tables later in this guide) using the button.

4. Push the needle pins or the heavy duty moisture probe pins into the wood and observe the reading.

5. Press and hold the power button to shut the meter off.

Manual Temperature Correction (for use without the Temperature Probe)

The instrument is calibrated for wood at 68°F (20°C). In general, wood that is warmer than

68°F (20°C) will give higher readings and wood colder than 68°F (20°C) will give lower readings. An approximate manual correction of 0.5% moisture content per 9°F (5°C) may be subtracted from wood that is above 68°F (20°C). For wood that is below 68°F (20°C), a manual correction of 0.5% moisture content per 9°F (5°C) may be added to the measured value.

Automatic Temperature Correction ATC (for use with the Temperature Probe)

1. Switch the instrument on and select the appropriate wood calibration scale as detailed earlier.

2. Using a hammer and nail of a nominal 3 mm diameter, make a hole in the wood to be tested.

3. Remove the nail and push the Temperature Probe into the hole until the tip is at the required depth.

4. Connect the Temperature Probe into the instrument via the Temp socket.

5. Measure the wood as described earlier to obtain the automatically temperature corrected (ATC) moisture value.

6. To read the current temperature of the wood press the T button, the LCD will display the temperature.

Auto Power OFF

The meter can automatically turn itself off after several minutes. This is to conserve on battery energy. The user can select the period of time the meter must remain idle before turning itself off (1 through 9 minutes). The user can also elect to disable the automatic power off feature (select 00).

1. With the meter ON, simultaneously press the power and the right arrow buttons. The current time period will appear.

2. While continuing to hold the power button, use the right arrow button to select the desired time period. Select ‘00’ to disable this feature.

3. Release both buttons when the desired value is on the LCD.

4 MO220 V1..2 4/10

Manual Accuracy Check

There are two (2) sets of calibration poles located inside the meter’s protective cover.

One set is for the 18% calibration and the other is for the 26% calibration, as marked inside the cover.

When checking the calibration, the A scale should be selected and the temperature probe must be disconnected.

Touch the two measurement pins to the 18% calibration nodes and view the measurement on the meter display. Do the same for the 26% calibration.

When correctly calibrated, the instrument will register %H2O values in the range of

17.7 to 18.3 (18% calibration) and in the range of 25.5 to 26.5 (26% calibration).

If the tolerance exceeds ±1 the instrument must be recalibrated.

Care and Maintenance

When the instrument is not in use, keep it in its pouch together with its accessories. Store the kit in a stable, dust-free environment out of direct sunlight. Remove the batteries from the instrument if it is to be stored for periods of more than one month, or when the low battery power symbol appears on the display. Check the condition of accessories used with the instrument on a regular basis and replace them if they become worn or damaged.

Battery replacement

When the low battery icon appears on the display, replace the battery as soon as practical.

1. Remove the rear battery compartment screw.

2. Remove the battery compartment door

3. Replace the two (2) ‘AAA’ 1’5V batteries

4. Replace the compartment door and secure the screw before using the meter.

5 MO220 V1..2 4/10

Calibration Tables for Wood

Wood Species Group Tables

Common names of wood (BS-888 & 589:1973)

Wood Species Group

Abura E

Aformosa G

Afzelia E

Amboyna

Ash, American

Ash, European

Ash, Japanese

Baguacu, Brazilian

G

B

A

A

F

Basswood G

Beech, European C

Berlina B

Binvang E

Birch, European J

Birch, Yellow

Bisselon

A

E

Bitterwood

Blackbutt

F

C

Bosquiea

Boxwood, Maracaibo

A

A

Camphorwood, E African

Canarium, African

C

B

Cherry, European J

Chestnut C

Coachwood G

Cypress, E African

C

Dahoma A

Danta C

Douglas Fir B

Elm, English

Elm, Rock

Elm, White

Empress, Tree

Erimado

E

E

E

J

F

Fir, Douglas

Fir, Grand

Fir, Noble

B

A

J

6 MO220 V1..2 4/10

Wood Species Group

Greenheart C

Guarea, Black J

Guarea, White H

A

Gum, Saligna

Gum, Southern

Gum, Spotted

B

B

A

Gurjun A

Hemlock, Western C

Hickory F

Hyedunani B

Ironbank B

Jarrah C

Jelutong C

Karpur A

Keruing F

Kuroka A

Loliondo C

Mahogany, African

Mahogany, West Indian

J

B

Makore B

Mansoia B

Meranti, White B

Merbau B

Missanda C

Muhuhi J

Muninga G

Musine J

Musizi J

Naingon C

A

Oak, European

Oak, Japanese

Oak, Tasmanian

A

A

A

C

Oak, Turkey E

Obeche G

Odoko E

7 MO220 V1..2 4/10

Wood Species Group

Okwen B

Olive, E African B

Olivillo G

Opepe H

Padang A

Padauk, African F

Persimmon

Pillarwood

Pine, Bunya

Pine, Corsican

Pine, Hoop

Pine, Huon

G

F

C

B

C

C

C

B

B

E

A

B

Pine, Kauri

Pine, Lodgepole

Pine, Maritime

Pine, Parana

Pine, Ponderosa

Pine, Radiata

Pine, Red

Pine, Scots

C

B

C

C

B

A

Pine, Sugar

Pine, Yellow

C

A

Poplar, Black A

Pterygota, African A

Pyinkado

Queensland Kauri

E

J

Queensland Walnut C

Ramin G

Redwood, Baltic (European) A

Redwood, Californian

Rosewood, Indian

Rubberwood

B

A

H

Sapele C

Seraya, Red C

C

C

Spruce, Sitka C

Stringybark, Messmate

Stringybark, Yellow

C

C

Sterculia, Brown

Sycamore

Tallowwood

A

F

A

8 MO220 V1..2 4/10

Wood Species Group

Totara E

Turpentine C

Walnut, African J

Walnut, American A

Walnut, European C

Walnut, Queensland C

Wawa G

Wandoo J

Whitewood C

9 MO220 V1..2 4/10

Botanical Names of Wood

Wood Type Grp

Abies grandis A

Abies procera

Acanthopanex ricinifolius

J

A

Acer macrophyllum

Acer pseudoplatanus

A

F

Acer saccharum A

Aetoxicon punctatum G

Aformosia elata G

Afaelia spp E

Agathis palmerstoni J

Amblygonocarpus andgensis

Amblygonocarpus obtusungulis

A

A

Araucaria angustifolia B

Araucaria bidwilli B

Araucaria cunninghamii

Berlinia grandiflora

Berlinia spp

B

B

Betula alba J

Betula alleghaniensis J

Betula pendula J

Betula spp J

Bosquiera phoberos A

Brachylaena hutchinsii J

Brachylaena spp B

Calophyllum brasiliense H

Cardwellia sublimes C

Cassipourea elliotii F

Cassipourea melanosana F

Castanea sutiva C

Ceratopetalum apetala

Chamaecyparis spp

Chamaecyparis spp

Chlorophora excelsa

(8-18%mc)

G

G

(18-28%mc)

C

F

Cordial alliodora

Corton megalocarpus

F

J

Cryptomelia japonica B

Cupressus spp A

Dalbergia latifolia A

Diospyros virginiana G

Dipterocarpus (Keruing) F

Dipterocarpus zeylanicus A

Distemonanthus benthamianus

Dracontomelium mangiferum

C

B

Dryobanalops spp A

Dyera costulata C

10 MO220 V1..2 4/10

Wood Type

Entandrophragma angolense

Entandrophragma cylindricum

Entandrophragma utile

Erythrophleum spp

Grp

H

C

J

C

Eucalyptus crebra B

Eucalyptus diversicolor A

Eucalyptus globules B

Eucalyptus maculate A

Eucalyptus marginata C

Eucalyptus microcorys A

Eucalyptus obliqua C

Eucalyptus pilularis C

Eucalyptus saligna B

Eucalyptus wandoo J

Fagus sylvatica C

Flindersia brayleyana B

Fraxinus Americana B

Fraxinus mardshurica

Gossweilodendron balsamiferum

Gossypiospermum proerox

A

J

A

Guarea thomsonii

Guibortia ehie

Hevea barsilensis

J

B

H

Juglans nigra A

Juglans regia C

Khaya senegalensis

Khaya ivorensis

Larix deciduas

E

J

C

Larix kaempferi

Larix leptolepis

C

C

Larix occidentalis F

Liquidamper styraciflua A

Lovoa klaineana

Lovoa trichiloides

J

J

Maesopsis eminii J

Mansonia altissima B

Millettia stuhimannii A

Mimusops heckelii B

Mitragyna ciliate E

Nauclea diderrichii H

Nesogordonia papaverifera C

Ochroma pyramidalis

Ocotea usambarensis

11

A

C

MO220 V1..2 4/10

Wood Type Grp

Octomeles sumatrana E

Olea hochstetteri B

Olea welwitschii

Palaquium spp

C

A

Paulownia tomentosa J

Pericopsis elata G

Picea sitchensis

Pinus caribaea

Pinus contorta

Pinus lampertiana

J

C

C

C

A

C

Pinus palustris

Pinus pinaster

Pinus ponderosa

C

B

C

Pinus spp B

Pinus strobus

Pinus sylvestris

A

A

Pinus thunbergii

Pipadeniastrum africanum

B

A

Piptadenia africana A

Podocarpus dacrydiodes B

Podocarpus spicatus C

Podocarpus totara

Populus spp

E

A

Pseudotsuga menzesii B

Pterocarpus angolensis G

Pterocarpus indicus G

Pterocarpus soyauxii F

Quercus cerris E

Quercus delegatensis

Quercus gigantean

C

C

Quercus robur A

Quercus spp A

Ricinodendron heudelotti

Sarcocepalus diderrichii

F

H

Sequoia sempervirens B

Shorea smithiana G

Shorea spp B

Sterculia rhinopetala A

Swietenia candollei A

Swietenia mahogani B

Syncarpia glomulifera C

Syncarpia laurifolia C

Tarrietia utillis C

Taxus baccata C

12 MO220 V1..2 4/10

Wood Type Grp

Terminalia superba A

Tieghamella heckelii B

Tilia anericana

Tilia vulgaris

G

E

Triploehiton scleroxylon G

Tsuga heterophylia

Ulmus amercana

C

E

Ulmus thomasii

Xylia dolabriformis

E

E

NOTES:

The calibration data in this table are based on standard tests by oven-drying of commercial samples of the various wood species, between 7% and fibre saturation.

Above the fibre saturation point (25%-30%) readings are approximate and generally apply to wood that has been dried and re-wetted.

The instrument is calibrated for wood at 68°F (20°C). If the temperature of wood varies by more than 5°C, the meter reading can be corrected approximately by adding 1/2% for every 9F (5°C) below 68°F (20°C) or subtracting 1/2% for every 9F

(5°C) above 68°F (20°C).

Readings higher by 1%-2% may be obtained where wood has been impregnated with a water-borne preservative.

High readings obtained with some ply-woods of peculiar composition must be treated with caution.

13 MO220 V1..2 4/10

Building material measurements: Select the ‘A’ scale to measure building materials.

Refer to the following conversion table to obtain the building material moisture value.

Std

Scale

A

Bldg

Mat’l Species Group

B C E F G H J

Chip- board

%H2O

6 3

7 4.8 9.2 9.4 8.6 6.8 6.7 11.0 10.1

8 7.0 10.0 9.3 7.4 7.4 11.5 11.0

9 8.7 10.8 9.7 7.9 8.1 12.1 11.6

8.5

10 10.5 11.7 11.5 10.4 8.6 8.8 12.7 12.2

9.4

11 12.2 12.7 12.6 11.3 9.5 9.7 13.4 13.4

10.5

12 13.3 13.6 13.7 12.1 10.5 10.5 14.0 14.3

11.5

13 14.8 14.5 14.5 12.7 11.2 11.2 14.5 15.1

12.5

14 16.2 15.3 15.5 13.4 11.8 11.8 15.0 16.0

13.5

15 16.6 16.3 16.7 14.1 12.5 12.6 15.6 17.0

14.4

16 17.2 16.9 17.5 14.8 13.0 13.2 16.0 17.7

14.9

17 18.8 17.7 18.8 15.7 14.3 13.9 16.6 18.5

15.3

18 19.6 18.2 19.7 16.3 15.0 14.5 17.0 19.1

16.1

19 20.2 19.0 21.0 16.9 15.9 15.2 17.6 20.0

16.7

20 20.6 20.0 22.6 17.8 16.9 16.1 18.4 21.3

17.2

21 20.9 20.8 23.5 18.5 17.6 16.8 19.1 22.3

18.3

22 21.5 21.5 24.5 29.3 18.3 17.4 19.7 23.2

19.1

23 22.1 22.9 26.4 20.2 19.8 18.6 21.2 24.5

19.9

24 22.7 23.5 27.4 20.8 20.4 19.0 22.0 25.8

20.5

25 23.2 24.2 27.8 21.2 21.0 19.4 22.7 26.3

23

26 23.6 25.3 29.0 22.4 22.3 20.1 23.9 27.3

27 24.0 26.6 30.0 23.3 23.5 20.8 24.9 28.2

28 24.2 27.9 31.2 24.2 24.6 21.6 25.7 29.2

29 24.4 29.3 32.5 25.6 26.0 22.9 26.9 30.2

30 24.6 30.8 33.7 26.8 27.5 24.1 28.2 31.1

14 MO220 V1..2 4/10

Warranty

EXTECH INSTRUMENTS CORPORATION warrants this instrument to be free of defects in parts and workmanship for one year from date of shipment (a six month limited warranty applies to sensors and cables). If it should become necessary to return the instrument for service during or beyond the warranty period, contact the Customer Service Department at (781) 890-7440 ext. 210 for authorization or visit our website www.extech.com for contact information. A Return Authorization (RA) number must be issued before any product is returned to Extech. The sender is responsible for shipping charges, freight, insurance and proper packaging to prevent damage in transit. This warranty does not apply to defects resulting from action of the user such as misuse, improper wiring, operation outside of specification, improper maintenance or repair, or unauthorized modification. Extech specifically disclaims any implied warranties or merchantability or fitness for a specific purpose and will not be liable for any direct, indirect, incidental or consequential damages. Extech's total liability is limited to repair or replacement of the product. The warranty set forth above is inclusive and no other warranty, whether written or oral, is expressed or implied.

Support line (781) 890-7440

Technical support: Extension 200; E-mail: [email protected]

Repair & Returns: Extension 210; E-mail: [email protected]

Product specifications subject to change without notice

For the latest version of this User’s Guide, Software updates, and other up-to-theminute product information, visit our website: www.extech.com

Extech Instruments Corporation, 285 Bear Hill Rd., Waltham, MA 02451

Copyright © 2007 Extech Instruments Corporation

All rights reserved including the right of reproduction in whole or in part in any form.

15 MO220 V1..2 4/10