Introduction
This manual provides detailed instructions for the operation, maintenance, and troubleshooting of your MESTEK WM700A Non-Contact Wood Moisture Tester. Please read this manual thoroughly before using the device to ensure safe and effective operation. The WM700A is a versatile tool designed for non-destructive measurement of moisture levels in various materials, including wood, drywall, and masonry.
1. Setup
1.1 Package Contents
Verify that all items are present in the package:
- 1x WM700A Non-Contact Wood Moisture Meter
- 1x User Manual
1.2 Battery Installation
The WM700A requires 3 AAA 1.5V batteries (not included). To install the batteries:
- Locate the battery compartment on the back of the device.
- Open the battery compartment cover.
- Insert 3 AAA batteries, ensuring correct polarity (+/-).
- Close the battery compartment cover securely.
1.3 Initial Power On and Zero Calibration
After installing batteries, press the power button (Power Switch Key) to turn on the device. The device features an AUTO-ZERO function. For accurate measurements, it is recommended to perform a zero calibration before use:
- Ensure the device is held in the air, away from any objects that could interfere with the sensor.
- Press the ZERO button. The display should show '0.0' or a similar indication of successful calibration.
2. Operating Instructions
2.1 Power On/Off
- Press the Power Switch Key (red button with power symbol) to turn the device ON.
- Press and hold the Power Switch Key to turn the device OFF.
- The device features an Auto Power Off function, which will turn off the device after 10 minutes of inactivity to conserve battery life.
2.2 Mode Selection
The WM700A offers four measurement modes for different materials. Press the SEL button to cycle through the modes:
- Drywall Pattern
- Masonry Pattern
- Softwood Pattern
- Hardwood Pattern
2.3 Taking Measurements
The WM700A uses a high-precision electromagnetic wave sensor for non-destructive measurements.
- Select the appropriate material mode using the SEL button.
- Place the back of the device, where the electromagnetic sensor is located, flat against the surface of the object to be measured.
- Ensure the thickness of the measured object is greater than 20mm, and the area is greater than 40x40mm for accurate readings.
- The moisture level will be displayed on the LCD screen.
2.4 Data Hold Function
To retain a measurement on the display:
- Press the HOLD button while a measurement is displayed.
- The reading will be frozen on the screen.
- Press the HOLD button again to release the data and resume live measurements.
2.5 Unit Conversion (°C/°F)
To switch between Celsius and Fahrenheit for ambient temperature readings:
- Press the °C/°F button.
- The temperature unit on the display will change accordingly.
2.6 Ambient Temperature and Humidity Detection
The device includes sensors to detect and display the ambient temperature and humidity of the surrounding environment.
2.7 Over-Range Alarm Function
The WM700A features an audible alarm to indicate high moisture levels:
- For Drywall and Masonry patterns, the buzzer will sound if the detected value exceeds 70%.
- For Softwood and Hardwood patterns, the buzzer will sound if the detected value exceeds 17%.
3. Maintenance
3.1 Cleaning
- Wipe the device with a soft, dry cloth.
- Do not use abrasive cleaners or solvents, as these may damage the casing or display.
- Keep the sensor area clean and free from dust or debris for accurate readings.
3.2 Storage
- When not in use for extended periods, remove the batteries to prevent leakage.
- Store the device in a dry environment, away from direct sunlight and extreme temperatures.
- Recommended storage environment: -10~50°C (5%~95% RH).
3.3 Battery Replacement
When the battery indicator on the display shows low power, replace the batteries promptly to ensure continued accurate operation. Follow the battery installation steps in Section 1.2.
4. Troubleshooting
| Problem | Possible Cause | Solution |
|---|---|---|
| Device does not power on | Dead or incorrectly installed batteries. | Replace batteries with new 1.5V AAA batteries, ensuring correct polarity. |
| Inaccurate readings | Sensor area is dirty; object too thin or small; incorrect mode selected; device not zero-calibrated. | Clean sensor area. Ensure object thickness > 20mm and area > 40x40mm. Select correct material mode. Perform zero calibration. |
| "HI" displayed on screen | Measurement value is outside the device's range or indicates very high moisture. | This indicates a very high moisture level. Refer to the Over-Range Alarm function in Section 2.7. |
| Buzzer alarm sounds continuously | Moisture level exceeds the alarm threshold for the selected material. | The alarm indicates high moisture. Refer to the Over-Range Alarm function in Section 2.7 for specific thresholds. |
5. Specifications
| Feature | Detail |
|---|---|
| Model Number | WM700A |
| Display Type | VA Full Viewing Angle Reverse Display Color Screen (LCD Digital) |
| Measurement Modes | Drywall, Masonry, Softwood, Hardwood |
| Measuring Range (Softwood) | 0% ~ 55% |
| Measuring Range (Hardwood) | 0% ~ 35% |
| Measuring Range (Drywall & Masonry) | Relative values |
| Precision (Softwood, Hardwood) | ±4% |
| Detection Thickness | 4/3 inch (20mm) |
| Sensor Type | Electromagnetic Wave Sensor (Non-destructive) |
| Automatic Shut-down | 10 minutes |
| Battery | 3 x 1.5V AAA (not Included) |
| Working Current | 35mA |
| Operating Temperature | 0°C ~ 40°C |
| Working Humidity | 0% ~ 70% |
| Storage Environment | -10°C ~ 50°C (5% ~ 95% RH) |
| Dimensions (Approx.) | 136.5mm (Height) x 78.5mm (Width) x 39mm (Depth) |
6. Warranty and Support
For any questions, technical assistance, or warranty claims, please contact the seller or manufacturer directly. Keep your purchase receipt as proof of purchase.
7. User Tips
- Always perform a zero calibration in the air before taking measurements to ensure accuracy.
- When measuring, ensure the sensor is fully in contact with the surface and the object meets the minimum thickness and area requirements (20mm thickness, 40x40mm area).
- The device measures relative humidity for drywall and masonry. For precise comparisons, measure a known dry area first.
- Pay attention to the over-range alarm, as it provides an immediate indication of potentially problematic moisture levels.
