1. Important Safety Information
Please read this manual thoroughly before operating the Yanmis WT100A Ultrasonic Thickness Tester. Keep this manual for future reference.
- Do not attempt to disassemble or modify the device. This may void the warranty and cause damage.
- Ensure the device is used within its specified operating temperature range (0-40°C).
- Avoid exposing the device to strong impacts, vibrations, or corrosive substances.
- Use only the specified coupling agent for measurements to ensure accuracy and prevent damage to the probe.
- Keep the device and accessories out of reach of children.
2. Product Overview
The Yanmis WT100A is a microprocessor-controlled ultrasonic thickness tester designed for quick and accurate measurement of various materials. It utilizes ultrasonic waves to determine thickness without causing damage to the material. This device is suitable for measuring metal, plastic, ceramic, glass, and other materials that conduct and reflect sound waves consistently.

Figure 2.1: Front view of the Yanmis WT100A Ultrasonic Thickness Tester, showing the display and control buttons.
Key Features:
- High digital precision for accurate thickness measurements.
- USB charging capability.
- Suitable for a wide range of materials including metals, plastics, ceramics, and glass.
- Microprocessor controlled for reliable performance.
- Capable of monitoring corrosion levels in pipes and production equipment.
3. Package Contents
Upon unpacking, please verify that all items listed below are present and in good condition:

Figure 3.1: The WT100A device, carrying case, USB cable, instruction manual, coupling agent, and probe.
- Yanmis WT100A Ultrasonic Thickness Tester Unit
- Ultrasonic Probe (Standard 5MΦ10)
- USB Charging Cable
- Coupling Agent Bottle
- Carrying Case
- User Manual
4. Setup
4.1 Connecting the Sensor
Before use, connect the ultrasonic probe to the main unit. Ensure the connectors are securely fastened.
Video 4.1: Demonstrates connecting the sensor to the ultrasonic thickness gauge and initial power-on.
4.2 Applying Coupling Agent
The coupling agent is essential for transmitting ultrasonic waves between the probe and the material being measured. Apply a small amount of coupling agent to the surface of the probe or the material before taking a measurement. Without the coupling agent, the device will not display accurate readings.
Video 4.2: Shows the application of coupling agent to the probe for effective measurement.
5. Operating Instructions
5.1 Powering On/Off
Press and hold the MENU button (power symbol) to turn the device on or off.
5.2 Selecting Material and Sound Speed
Different materials have different sound velocities. To ensure accurate measurements, select the correct material type or manually input the sound speed.
- Press the VEL key to access the sound speed selection menu.
- Use the UP and DOWN arrow keys to navigate through the list of materials or to adjust the sound speed value.
- Press OK to confirm your selection.
Video 5.1: Demonstrates how to select the medium and sound speed using the VEL key.
5.3 Calibration
For optimal accuracy, calibrate the device using a known standard sample before taking critical measurements.
- Apply coupling agent to the standard sample.
- Place the probe firmly on the standard sample.
- Access the menu and navigate to the 'Calibration' option.
- Follow the on-screen prompts to complete the calibration process.

Figure 5.2: Calibrating the device by placing the probe on a standard metal block of known thickness.
5.4 Taking Measurements
After setup and calibration:
- Ensure the correct material sound speed is selected.
- Apply coupling agent to the surface of the material to be measured.
- Press the probe firmly and steadily against the material surface.
- The thickness reading will appear on the display.
- Remove the probe to automatically save the measurement (if autosave is enabled).
Video 5.3: Demonstrates the process of taking thickness measurements on various materials.
5.5 Data Management (Save/Clear)
The device can store multiple sets of data across different files.
- Press the ESC key to access options for saving or clearing current data.
- The device supports 15 files, each capable of storing 100 sets of data.
- Autosave function automatically stores data after measurement.
Video 5.4: Illustrates how to save or clear data and manage files within the device's memory.
5.6 Setting Alarms
You can set high and low thickness limits to trigger an alarm.
- Navigate to the 'Alarm' option in the menu.
- Set the desired High Limit and Low Limit values.
- The device will sound an alarm if measurements fall outside these limits.
Video 5.5: Shows how to set high and low alarm limits for thickness measurements.
5.7 Other Settings
The device offers various customizable settings:
- Unit Selection: Switch between millimeters (mm) and inches (in).
- Probe Selection: Choose the appropriate probe type (e.g., 5MΦ10, 2.5M, High Temperature).
- Language: Select the display language.
- Shutdown Time: Adjust the automatic shutdown timer.
- Key Sound: Enable or disable button press sounds.
- Backlight Function: Adjust display backlight settings.
- Restore Factory Settings: Option to reset all settings to default.
Video 5.6: Demonstrates how to adjust various settings including units, probe type, language, shutdown time, key sound, and backlight.
6. Applications
The WT100A Ultrasonic Thickness Tester is versatile and can be used across various industries for non-destructive thickness measurement.

Figure 6.1: The device is suitable for measuring thickness of various materials such as metal, plastic, ceramic, and glass.
Typical Use Cases:
- Manufacturing: Quality control for material thickness.
- Metal Processing: Checking the thickness of metal sheets, pipes, and components.
- Corrosion Monitoring: Assessing the extent of corrosion in pressure vessels, pipes, and other equipment.
- Material Inspection: Verifying thickness of plastic, ceramic, and glass products.

Measuring metal sheet thickness.

Measuring pipe thickness.

Measuring plastic thickness.
7. Specifications

Figure 7.1: Rear view of the device displaying technical specifications.
| Measurement Range | 1.00 ~ 225.0 mm |
| Accuracy | ± (0.5%H + 0.05) mm |
| Operation Frequency | 5 MHz |
| Sound Velocity Range | 1000 ~ 9999 m/s |
| Operation Temperature | 0 ~ 40°C |
| Battery | 3 * 1.2V Ni-MH rechargeable batteries |
| USB Charging Socket | 5V/1A |
| Product Dimensions | 3.94 x 3.94 x 3.94 inches (approx. 100 x 100 x 100 mm) |
| Item Weight | 1.65 pounds (approx. 0.75 kg) |
8. Maintenance
Proper maintenance ensures the longevity and accuracy of your device.
- Cleaning: After each use, wipe the probe and the device with a soft, dry cloth to remove any residual coupling agent or dirt. Do not use abrasive cleaners or solvents.
- Storage: Store the device in its carrying case in a cool, dry place, away from direct sunlight and extreme temperatures.
- Battery Care: If the device will not be used for an extended period, ensure the batteries are fully charged before storage. Recharge regularly if stored for very long periods.
- Probe Care: Handle the probe carefully. Avoid dropping it or subjecting it to excessive force, as this can affect its performance.
9. Troubleshooting
If you encounter issues with your WT100A, refer to the following common problems and solutions:
- No Reading or Inaccurate Reading:
- Ensure sufficient coupling agent is applied between the probe and the material.
- Verify that the probe is placed firmly and flat against the surface.
- Check if the correct material type and sound velocity are selected in the settings.
- Perform a calibration using a standard sample.
- Inspect the probe and cables for any visible damage.
- Device Not Powering On:
- Check battery charge level. Connect to USB charger.
- Ensure batteries are correctly inserted.
- Display Issues:
- Adjust backlight settings in the menu.
- If the display is frozen, try restarting the device.
If the problem persists after attempting these solutions, please contact customer support.
10. Warranty and Support
For information regarding warranty coverage, technical support, or service, please refer to the warranty card included with your product or visit the official Yanmis website. Contact details for customer service are typically provided in the product packaging or on the manufacturer's support pages.