1. Introduction
This manual provides detailed instructions for the safe and effective use of the Benetech GM620 Wood Moisture Meter. The GM620 is a precision instrument designed to measure the moisture content of various wood types, as well as environmental temperature and humidity. It features adjustable settings for different wood species, automatic temperature compensation, and a clear LCD display with backlight.
2. Safety Information
Please read and understand all safety instructions before operating the device. Failure to follow these instructions may result in injury or damage to the meter.
- Keep the device away from water and high humidity environments to prevent electrical shock or damage.
- Do not attempt to disassemble or modify the meter. Repairs should only be performed by qualified personnel.
- Handle the measurement probes with care. They are sharp and can cause injury.
- Remove batteries if the device will not be used for an extended period to prevent leakage.
- Dispose of batteries and the device according to local regulations.
3. Product Overview
The Benetech GM620 Wood Moisture Meter is designed for accurate and convenient moisture content measurement. Key features include:
- Adjustable for 4 tree species groups.
- Reading lock function for stable measurements.
- Automatic temperature compensation for environmental variations.
- Maximum moisture reading review.
- Backlight on/off switch for visibility in various lighting conditions.
- Utilizes CPU technology for accurate measurements.
- Powered by 2 AAA batteries with a battery icon indicator.
- Large LCD for clear display of readings.
- Automatic power-off after 120 seconds of inactivity; manual turn-off also available.
- Capable of measuring environmental humidity and temperature.
- Compact, lightweight, and portable design.
Figure 1: Benetech GM620 Wood Moisture Meter with its external probe. The main unit features an LCD display showing temperature, humidity, and moisture percentage, along with 'M', 'HOLD', and 'SET' buttons. The external probe has two sharp pins for insertion into wood.
Figure 2: The Benetech GM620 Wood Moisture Meter retail box, displaying the product image and model number.
4. Setup
4.1 Battery Installation
- Locate the battery compartment cover on the back of the device.
- Slide or unclip the cover to open it.
- Insert two (2) 1.5V AAA batteries, ensuring correct polarity (+/-).
- Replace the battery compartment cover securely.
4.2 Connecting the External Probe
If using the external probe for measurement, connect its cable to the designated port on the top of the main meter unit.
Figure 3: The Benetech GM620 Wood Moisture Meter, external probe, and user manual neatly arranged within its protective packaging, ready for initial setup.
5. Operating Instructions
5.1 Power On/Off
- Press the POWER button (often integrated with the 'M' or 'SET' button, or a dedicated button) to turn the meter on.
- The meter will automatically turn off after 120 seconds of inactivity. To manually turn off, press and hold the POWER button.
5.2 Selecting Wood Species Group
The GM620 supports 4 different wood species groups (M1, M2, M3, M4) to ensure accurate readings for various wood densities. Refer to the table below for common wood types and their corresponding groups. Use the SET button to cycle through the groups.
| Group | Wood Species Examples | Density Range (g/cm³) |
|---|---|---|
| M1 (Group A) | Teak, Walnut, Afrormosia, Rubber Tree, Imbuia, Kokrodua, Niove Bidinkala, Cork | ~0.65 - 0.80 |
| M2 (Group B) | White Poplar, Keruing, Beech, Cedar, Tola, Larch, Birch, Fir, Elm, Aspen, Maple, Padauk, Oak, Cherry | ~0.45 - 0.65 |
| M3 (Group C) | Lauan, Ash, Elm, Juniper, Maple, Padauk, Oak, Cherry, Basswood, Pine, Poplar | ~0.35 - 0.45 |
| M4 (Group D) | Larch, Pine, Birch, Fir, Elm, Aspen, Maple, Padauk, Oak, Cherry | ~0.25 - 0.35 |
5.3 Taking a Moisture Measurement
- Ensure the correct wood species group is selected (refer to 5.2).
- Carefully insert the measurement pins of the external probe (or integrated pins if applicable) into the wood surface. Ensure both pins penetrate the material to a sufficient depth for good contact.
- Read the moisture content percentage displayed on the LCD screen.
- To hold the current reading, press the HOLD button. Press it again to release.
- To review the maximum moisture reading, press the M (Memory/Max) button.
5.4 Environmental Measurement
The GM620 also displays ambient temperature and humidity. These readings are typically shown on the upper part of the LCD screen automatically.
5.5 Backlight Control
Press the LIGHT button (often integrated with another button, e.g., long press 'HOLD' or 'M') to turn the LCD backlight on or off for improved visibility in low-light conditions.
6. Maintenance
- Cleaning: Wipe the meter with a soft, dry cloth. Do not use abrasive cleaners or solvents.
- Storage: Store the device in a cool, dry place, away from direct sunlight and extreme temperatures. Remove batteries if storing for extended periods.
- Probe Care: Keep the measurement pins clean and free from debris. Replace bent or damaged pins to ensure accurate readings.
7. Troubleshooting
| Problem | Possible Cause | Solution |
|---|---|---|
| Meter does not power on. | Dead or incorrectly installed batteries. | Check battery polarity, replace with new AAA batteries. |
| Inaccurate or inconsistent readings. | Incorrect wood species group selected; poor probe contact; damaged probes; environmental interference. | Verify wood group setting; ensure pins fully penetrate; inspect and replace probes if damaged; avoid strong electromagnetic fields. |
| LCD display is dim or blank. | Low battery; backlight off. | Replace batteries; press the backlight button to turn it on. |
8. Specifications
| Parameter | Value |
|---|---|
| Moisture Measurement Range | 2% ~ 70% (depending on wood group: 2~40%/50%/60%/70%) |
| Moisture Measurement Error | ±1% |
| Temperature Measurement Range | -10°C ~ 60°C (14°F ~ 140°F) |
| Humidity Measurement Range | 20%RH ~ 90%RH |
| Display Type | LCD with Backlight |
| Power Supply | 2 x 1.5V AAA Batteries |
| Automatic Power-Off | Approx. 120 seconds of inactivity |
| Dimensions | 135.6mm x 55mm x 29.4mm |
| Weight | 107.7g (without batteries) |
| Special Features | Auto Temperature Compensation, Reading Lock, Max Reading Review, Adjustable Wood Species Groups |
9. Warranty and Support
For warranty information and technical support, please refer to the documentation provided with your purchase or contact the manufacturer directly. Keep your purchase receipt as proof of purchase for warranty claims.
