Extech Instruments MO57 User manual

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USER MANUAL
Pinless Moisture Meter
Model MO57
Introduction
Thank you for selecting the Extech MO57 Pinless Moisture Meter. The MO57 employs a non-
destructive spherical sensor that safely glides over surfaces to measure the relative moisture in
wood and other building materials (wallboard, sheet rock, cardboard, plaster, concrete, and mortar)
at any angle to a depth of 10.2cm (4”).
To indicate moisture level the MO57 provides a digital reading, audible tones, and ‘moisture droplet’
icons. Audible tones (eight levels of intensity) and droplet icons (1, 2, or 3) increase in proportion to
increased moisture. Additional features include Auto Power OFF and Display Lock (hold).
This meter ships fully tested and calibrated and, with proper use, will provide years of reliable
service. Please visit our website (www.extech.com) to check for the latest version of this User Guide,
Product Updates, and Customer Support.
Measurement Considerations
To measure moisture, the sensor emits and senses low-power electro-magnetic signals. The
displayed reading in percent is an average of the moisture content measured over the measurement
surface area and the maximum depth of penetration (10.2cm [4.0”]). Moisture that is closer to the
surface has a greater effect on the displayed average than the moisture nearer to the maximum
depth of penetration.
Placing the sensor on a surface whose thickness is less than the maximum depth of penetration may
result in unreliable moisture readings; in these cases, you can stack material on top of the measured
surface to increase the thickness.
The MO57 also produces audible tones and ‘moisture droplet’ display icons to indicate moisture
level. The audible tone rate and number of droplets increase as the moisture level increases. When
measuring, keep hand stationary on the meter while holding and moving the meter, as hand
movement can affect the readings.
Meter Description
1. LCD Display
2. Power button
3. Display Lock/Beeper button
4. Material Select button
5. Sensor
Note: Battery compartment on rear of meter
Display Description
1. Droplet icons (1 for low moisture, 2 for medium, and 3 for high)
2. Wood mode
3. Building Material mode
4. Beeper active icon
5. Moisture reading
6. Percent moisture unit (relative)
7. Display Lock mode
8. Battery status icon
Button Descriptions
Symbol
Button name
Description
Power ON-OFF Long press to switch the meter ON or OFF
/
Material Select (wood/building
materials)
Short press to toggle material groups
/Display Lock / Beeper control
Short press locks/unlocks reading on the display
Long press toggles the Beeper ON/OFF
Operation
Powering the Meter
1. Long press the power button to turn the meter ON/OFF.
2. The meter emits audible tones and performs a self-calibration upon start-up. Keep the
measurement sensor at least 8 to 10 cm (3 to 4”) from hands and objects during calibration.
The calibration reading must not exceed 0.5. If so, re-calibrate ensuring that hands or other
objects are clear of the sensor. Note: Calibrate the meter whenever moving from one
measurement area to another.
3. If the battery symbol appears or if the meter does not switch ON, replace the battery.
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MO57-en-GB_V1.0 7/17
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Auto Power OFF
The meter will automatically power OFF if the reading stays 0% for 3 minutes. If the meter detects
readings, other than 0%, it will not automatically power OFF.
Display (Hold) Lock
Short press the Display Lock button to freeze the displayed reading. The icon is visible on
the display when Display Lock is active. Press again to return to the normal operating mode.
Beeper ON/OFF
The beeper defaults to ON. To switch the beeper OFF, long press the Display Lock/Audible Beeper
button . When the beeper is active, the audio display icon will be visible.
Pinless Moisture Measurements
1. Short press the Material Select button ( ) to toggle the Wood and Building Material
modes of operation. The displayed icon indicates the selected mode.
2. To take a measurement, hold the meter and position the sensor so that it is directly touching
the surface under test (at any angle). The meter can sense moisture to a depth of 10.2cm (4”).
NOTE: The position of your hand can affect the reading. Do not move or reposition the hand
that holds the meter while taking measurements or when powering the unit.
3. Observe the displayed relative readings, view the displayed moisture droplet icon(s) (more
drops indicate higher moisture levels), and listen for the audible beeping (faster beeping
indicates higher moisture; there are eight intensity levels). As discussed in the Measurement
Considerations section, the displayed reading is an average of the moisture measured over the
tested surface area to the maximum penetration depth.
4. Long press the power button to power OFF the meter.
Relative Moisture Reading Reference Table
WOOD (%)
BUILDING MATERIAL (%)
TOTAL RANGE >
0.1~99.9
0.1~99.9
LOW
0.1~9.9
0.1~9.9
10.0~16.9
10.0~16.9
MEDIUM
17.0~23.9
17.0~23.9
24.0~29.9
24.0~29.9
30.0~39.9
30.0~39.9
HIGH
40.0~59.9
40.0~59.9
60.0~69.9
60.0~69.9
70.0~99.9
70.0~99.9
Maintenance
Battery Replacement
When the battery status icon appears empty or flashing, replace the battery.
1. Remove the battery cover by pushing the compartment latch (bottom, back of meter).
2. Replace the 9V battery observing correct polarity.
3. Replace the battery cover securely.
4. Dispose of battery responsibly and within applicable legal regulations.
Never dispose of used batteries or rechargeable batteries in household waste.
As consumers, users are legally required to take used batteries to appropriate
collection sites, the retail store where the batteries were purchased, or wherever
batteries are sold.
Disposal: Do not dispose of this instrument in household waste. The user is obligated to take
end-of-life devices to a designated collection point for the disposal of electrical and electronic
equipment.
Care and Cleaning
•Store the meter in an environmentally stable, dust-free environment, out of direct sunlight.
•Remove the battery from the instrument if the meter is to be stored for long periods or if
the battery power symbol appears empty (or flashing) on the display.
•To clean the meter case, wipe with a damp cloth, do not use solvents or abrasives.
Specifications
Display LCD with multi-function indicators
Sensor Type Pinless spherical sensor
Measurement Type Non-destructive, electro-magnetic sensing
Measurement Indication Digital, Moisture Droplet icons (1, 2, or 3 droplets) and audible tone with
eight levels of intensity indicating low to high moisture readings
Measurement Ranges:
Wood: Low: 0.1% to 16.9%; Medium: 17.0% to 39.9%; High: 40.0 to 99.9%
Building Materials: Low: 0.1% to 16.9%; Medium: 17.0% to 39.9%; High: 40.0 to 99.9%
Measurement depth Sensor detects to a depth of 10.2cm (4”)
Resolution 0.1%
Accuracy Relative readings only
Auto Power OFF After approx. three (3) minutes with 0% display reading.
Power supply One (1) 9V Battery; Consumption: < 40mA
Low Battery indication < 7.5VDC, approximately
Low Battery APO < 5.5VDC; APO will occur in 20 seconds, approximately
Operating conditions 5 ~ 45oC (41 ~ 113oF); 80%RH max.
Storage conditions 0 ~ 50oC (32 ~ 122oF); 85%RH max.
Dimensions 210 x 70 x 33mm (8.3 x 2.8 x 1.3")
Weight 155g (5.5 oz.) without battery