1. Introduction
Thank you for choosing the MASTFUYI Spherical Sensor Moisture Meter FY8869. This instrument is a multifunctional measuring device designed for non-destructive moisture measurement in various bamboo, wood products, and raw materials. Its ease of use and fast measurement capabilities make it an ideal choice for furniture and decoration professionals, as well as DIY enthusiasts. Please read this manual thoroughly to ensure correct usage and to master simple maintenance skills.
2. Product Components
The FY8869 Spherical Sensor Moisture Meter features a user-friendly design with clearly labeled components:
- Spherical Probe: The non-destructive sensing element.
- Display Screen: High-definition backlit color screen for clear readings.
- Power Button (O/SET): Long press to power on/off. Short press to enter alarm threshold setting mode.
- MAX Button: Displays the maximum measured value.
- MIN Button (°C/°F): Short press to toggle between Celsius and Fahrenheit, and to switch to minimum value display.
- ZERO/HOLD Button: Short press to clear data (for calibration) or to lock/unlock the data display.
- Flashlight Button: Short press to turn the flashlight on or off.
- Lighting Lamp: Integrated flashlight for low-light conditions.
3. Setup
3.1 Battery Installation
The instrument requires 3 AAA batteries (not included). To install:
- Locate the battery compartment on the back of the device.
- Open the battery compartment cover.
- Insert 3 AAA batteries, ensuring the correct polarity (+/-) as indicated inside the compartment.
- Close the battery compartment cover securely.
3.2 Initial Power On and Calibration
Before using the instrument for the first time or after each power-on, calibration is required for accurate measurements.
- Long press the Power Button (O/SET) to turn on the instrument.
- Press the ZERO/HOLD key. The word "CAL" will appear on the display.
- During calibration, ensure the instrument is held at least 100mm away from any object.
- Keep your hand position stable relative to the instrument during calibration, as hand position can affect the reading.
- Calibration is complete when "CAL" disappears. The display reading should not exceed 0.3. If it does, recalibrate, ensuring no hands or other objects are near the spherical probe.
4. Operating Instructions
4.1 Taking a Measurement
- After successful calibration, touch the instrument's spherical probe to the surface of the object to be measured.
- Slide the probe across the desired measurement area. The display will show the real-time moisture measurement value, along with the maximum (MAX) and minimum (MIN) values recorded during the current measurement session.
- To ensure accurate readings, hold the spherical probe perpendicular to the material and press it firmly against the surface.
- When measuring in corners or near edges, keep the distance from the probe to a corner greater than 10cm to avoid higher readings due to increased material in the sensing area.
4.2 Key Functions
- Power Button (O/SET): Long press to turn the instrument on or off. Short press to enter alarm threshold setting mode.
- ZERO/HOLD Button: Short press to clear data (after power-on for calibration). During measurement, short press to lock the current reading on the screen (Data Hold function). Press again to unlock.
- MIN Button (°C/°F): Short press to toggle the temperature unit between Celsius (°C) and Fahrenheit (°F). Also used to display the minimum recorded moisture value.
- Flashlight Button: Short press to turn the built-in flashlight on or off. Useful for measurements in low-light environments.
4.3 Alert Value Setting
The meter features a dual-stage alert setting, allowing you to adjust the threshold based on the material being measured. The display provides color-coded indicators for moisture levels:
- DRY: Low moisture content.
- MID (Moderate): Intermediate moisture content.
- WET (Humid): High moisture content, potentially indicating an issue.
Refer to the "Alert Threshold Reference Table" in the Specifications section for material-specific guidelines.
5. Specifications
| Parameter | Value |
|---|---|
| Model Number | FY8869 |
| Probe Length | 58mm |
| Measurement Depth | 5-40mm (0.2-1.57 inches) |
| Measurement Range | 0.1~99.9% (Relative Reading) |
| Accuracy | ±2.5% (at 25°C ambient temperature) |
| Operating Temperature | 0~45°C |
| Operating Humidity | 0~75% |
| Auto Shutdown | Yes |
| Unit Switch | Yes (°C/°F) |
| Auto Calibration | Press ZERO after power-on |
| Battery Specification | 3x AAA Batteries (Not included) |
| Product Dimensions | 199mm*60mm*30mm |
| Product Weight | Approx. 158g (Without batteries) |
| With Backlight | Yes |
| DIY Supplies | Woodworking |
| Certification | CE, FCC, RoHS |
5.1 Instrument Readings and Moisture Content Conversion Table
The instrument reading is a unitless value from 0 to 100, which is different from the CM% (calcium carbide) moisture content. The data in this table can be used by the user to convert instrument readings to CM% moisture content (indicative and non-binding).
| Instrument Reading | Plaster Moisture Content (CM%) | Cementitious Material Moisture Content (CM%) | Lumber Moisture Content (CM%) |
|---|---|---|---|
| 15 | 10.00 | ||
| 20 | 12.00 | ||
| 25 | 15.00 | ||
| 30 | 0.25 | 17.00 | |
| 35 | 0.30 | 2.50 | 20.00 |
| 40 | 0.40 | 2.65 | 23.00 |
| 45 | 0.65 | 2.85 | 25.00 |
| 50 | 1.00 | 3.20 | |
| 55 | 1.40 | 3.55 | |
| 60 | 1.70 | 4.00 | |
| 65 | 1.90 | 4.30 | |
| 70 | 2.05 | 4.70 | |
| 75 | 2.20 | 5.10 | |
| 80 | 2.35 | 5.45 | |
| 85 | 2.50 | 5.75 | |
| 90 | 2.65 | 6.10 |
5.2 Alert Threshold Setting Reference Table
Users can set the humidity alarm thresholds for different materials according to this table, which is for reference and not binding.
| Material | Displayed Value | Moisture Level |
|---|---|---|
| Plaster (Mineral) | <30 | DRY |
| 30-60 | MID | |
| >60 | WET | |
| Cementitious Material | <25 | DRY |
| 25~50 | MID | |
| >50 | WET | |
| Lumber | <50 | DRY |
| 50~80 | MID | |
| >80 | WET |
6. Maintenance
6.1 Cleaning
Clean the instrument with a soft, damp, lint-free cloth. Ensure no moisture enters the housing. Do not use sprays, solvents, alcohol-based cleaners, or abrasive cleaners. Only moisten the cleaning cloth with clean water.
6.2 Battery Replacement
When the instrument's power icon shows low battery, or it cannot be turned on due to depleted batteries:
- Open the battery compartment cover.
- Remove the old batteries.
- Insert new 3 AAA batteries, carefully observing the polarity markings (+/-) in the battery compartment.
- Close the battery compartment cover.
6.3 Repair
Do not attempt to disassemble or modify the instrument, or install any unauthorized accessories. For repairs, please contact the manufacturer or authorized service center.
7. Troubleshooting and Precautions
7.1 Dielectric Measurement Method
Dielectric measurement is an indirect method where the material's dielectric constant changes with moisture content. The instrument infers moisture content by measuring this constant. It is suitable for non-destructive moisture measurements of wood and mineral building materials. Note that the dielectric method provides a rough moisture value; for highly accurate results, more specialized equipment may be needed.
7.2 Factors Affecting Measurement Accuracy
- Bulk Density: Higher bulk density of the material can lead to higher measured values.
- Soluble Salts: An increase in soluble salts in the material increases conductivity and can result in excessively high readings.
- Temperature: Avoid measuring wood at temperatures below -5°C, as low temperatures can affect results.
- Material Homogeneity: Ideally, the material should be homogeneous and free from air pockets.
- Conducting Substances/Electric Fields:
- If the material contains electrically conductive substances (e.g., metal layer reinforcements, slag), the dielectric constant will increase, leading to excessively high readings.
- If metal objects (nails, screws) are within the sensor's measurement area, the reading will spike due to strong reflections.
- Avoid static charges from friction, as they distort measurement results. Wood with less than 10% moisture content can carry static charges.
- Under optimal conditions, no electric fields or conductive substances should be present in the material under test.
Impact of Metal on Measurement Readings - Surface Condition:
- Remove impurities (paint residue, dust) from the measurement point.
- Wood preservatives can affect measurements.
- Rough surfaces may lead to low or inaccurate measurements.
- The surface should be as flat as possible to ensure complete contact with the measuring probe.
- Moisture Distribution:
- If the material thickness is less than 2cm, neighboring material layers can affect the reading. It is recommended to stack the same material to be measured to a thickness greater than 2cm before measurement.
- For optimal results, moisture should be uniformly distributed in the material.
8. User Tips
- Consistent Hand Position: Always maintain a consistent hand position relative to the instrument, especially during calibration and measurement, to minimize variations in readings.
- Surface Preparation: For best results, ensure the measurement surface is clean and free of debris, paint, or other coatings that could interfere with the sensor.
- Multiple Readings: Take several readings in different spots within the area of interest to get a more comprehensive understanding of the moisture levels.
- Environmental Awareness: Be mindful of the surrounding environment. Extreme temperatures or the presence of strong electromagnetic fields can influence the meter's performance.
- Leak Tracing: When investigating potential leaks, start from a dry area and move towards the suspected wet area. A gradual increase in readings can help pinpoint the source of the leak.
9. Storage and Support
9.1 Transportation and Storage
To prevent damage, observe the following:
- Transportation: Use a suitable case to protect the instrument from external impacts.
- Storage: When not in use, store the unit in a dry place, protected from frost, heat, dust, and direct sunlight. Ensure the storage temperature complies with the technical data specifications (0-45°C). Remove batteries if storing for extended periods.
9.2 Support
For any questions, technical assistance, or support regarding your MASTFUYI Spherical Sensor Moisture Meter FY8869, please contact the manufacturer or your local distributor. Refer to the product packaging or seller information for contact details.
User manual (PDF) is available for download from the seller's website.
