User Manual

MO257 V1.0 04/10

Introduction

Congratulations on your purchase of the Extech MO257 Pinless Moisture Meter. The

pinless moisture sensor monitors the moisture in wood and other building materials without

causing surface damage. High frequency sensing technology allows the meter to take non-

invasive moisture measurements. User programmable alarms alert the user if moisture

measurements exceed alarm set-points. This meter is shipped fully tested and calibrated

and, with proper use, will provide years of reliable service.

Meter Description

1. Measurement sensor

2. Power ON-OFF button

3. LCD display

4. Measure (MEAS) button

5. UP and BACKLIGHT button

6. SET button

7. DOWN button

Battery compartment located on rear of unit

LCD Display

1. Low Battery icon

2. Main LCD display

3. MAX reading

4. MIN reading

5. HOLD function

6. Measurement alert

7. MAX mode icon

8. MIN mode icon

Battery Replacement

1. Turn off the meter

2. Remove the Philips head screw located on the rear of the unit

3. Lift off the rear battery cover

4. Replace the three (3) ‘AAA’ 1.5V batteries

5. Secure the rear battery cover