UNI-T UT343A Coating Thickness Gauge

UT343A is a high-performance coating thickness gauge that can measure coating thickness on both ferrous and non-ferrous metals. This device features high precision, non-destructive measurement, and functions for single-point, multi-point averaging algorithm, and quick judgment. It is widely used in manufacturing, metal processing, aerospace, marine mechanics, rail transport, scientific research, quality supervision, and other industries.

The product is based on the principles of electromagnetic induction and the eddy current measurement.
The principle of electromagnetic induction measurement is to measure the coating thickness according to the size of the magnetic flux flowing from the sensor through the non-ferrous magnetic coating into the ferromagnetic substrate. The symbol is Fe. It can measure non-conductive or conductive coatings on magnetically permeable metals such as iron and steel (for example: galvanized steel sheet).

The principle of eddy current measurement is to measure the coating thickness according to the difference in the eddy current formed by an AC magnetic field on a non-magnetic metal substrate (such as aluminum). The symbol is NFe. It can measure non-conductive coatings on non-magnetic metal materials such as aluminum and copper. The substrate must be metal, and the coating cannot conduct electricity.

Features:

1. The measurement method conforms to GB/T 4956 for non-magnetic coatings on magnetic substrates (magnetic method).
2. The measurement method conforms to GB/T 4957 for non-conductive coatings on non-magnetic substrates (eddy current method).
3. Two thickness measurement methods: magnetic and eddy current.
4. Automatic identification of ferrous or non-ferrous substrates.
5. High-precision, hard-wearing, stable sensor.

II. Accessories

Open the packing box and take out the gauge. Please double-check whether the following items are missing or damaged:

1. Coating thickness gauge — 1 pc
2. User manual — 1 pc
3. Standard coating thickness sheets — 1 set (5 pcs)
4. Ferrous substrate — 1 pc
5. Non-ferrous substrate — 1 pc
6. Sensor protective cover — 1 pc
7. AAA alkaline batteries — 2 pcs

III. Safety Instructions

1. Initialization self-test is needed for the gauge when it is powered on. When turning on the gauge, please do not put the sensor close to any metal objects (at least 5 cm away from them) and stay away from strong electromagnetic fields; otherwise, the meter will be unusable and need to be restarted under the above-mentioned environment.
2. Please keep the sensor clean and in good condition to avoid dust, oil, and other factors affecting the measurement accuracy.
3. Do not use or store the gauge in high-temperature, high-humidity, flammable, explosive, and strong magnetic field environments.
4. Clean the gauge casing with a soft cloth and mild detergent. Do not use abrasives or solvents to avoid damage to the gauge.
5. Do not disassemble or modify the gauge.
6. When the LCD displays the low battery symbol, replace the battery in time. Remove the battery if the gauge is not used for a long time.
7. The batteries are normal “AAA” alkaline batteries that cannot be charged.
8. The standard coating thickness sheets are high-precision accessories that are related to the accuracy of the gauge and need to be preserved properly to prevent scratches, corrosion, bending, and deformation of the surface.
9. The metal substrates also need to be preserved properly to prevent scratches, rust, oxidation, and deformation of the surface.

IV. Function Description

A. Product Structure

1. LED warning light
2. LCD screen
3. Power button
4. Up/value+
5. Rotate/cancel/delete
6. Down/value-
7. Sensor module
8. Battery door

B. Display Interface

1. View stored data
2. Stored data number
3. Calibration mode
4. Setting mode
5. Continuous measurement
6. Battery status
7. Higher limit
8. Lower limit
9. Ferrous substrate
10. Non-ferrous substrate
11. mil (unit)
12. μm (unit)
13. Stored data number symbol (rotated)
14. View stored data (rotated)
15. MAX/MIN/AVG value
16. Average
17. Minimum
18. Maximum
19. Higher limit (rotated)
20. Lower limit (rotated)
21. Ferrous substrate (rotated)
22. Non-ferrous substrate (rotated)
23. mil (rotated)
24. Measured value
25. μm (rotated)
26. Stored data number symbol

C. Buttons

V. Operating Instructions

A. Power on/off

• Power on: Long press the power button until the screen is on.
• Power off: Long press the power button until the screen displays “OFF” and then release it.

B. Normal Measurement

1. Long press the power button to turn on the gauge. The gauge displays the initialization process and enters the normal measurement mode after initialization is completed.
2. Estimate the coating thickness of the measured object and select the corresponding or close standard coating thickness sheet to calibrate on the measurement substrate.
3. A substrate with thickness or material close to the measured object and without coating should be selected as the measurement substrate as far as possible.
4. Please refer to the calibration chapter for the calibration method.
5. When measuring, select 3 to 5 measuring points on the surface of the measured object evenly, measure 5 times for each point, and take the average value of the 5 times as the indicating value of the point.
6. After the indicating values of the 3 to 5 measuring points are measured, the average of the values should be taken as the reference value of the object coating thickness.

Note:

• Hold the gauge perpendicular to the substrate to be measured and lightly press the sensor against the substrate for measurement. Keep the sensor in close contact with the substrate and avoid measurement error due to excessive force.
• If the measured value is greater than 1750um, the screen displays “OL” to indicate over range.
• If the measured value is greater than 2000um, the gauge will not respond.

C. Menu Settings

Long press the menu button in normal measurement mode to enter the menu settings mode. “SET” will show on the LCD.

• At this time, the interface is for setting the measurement unit. Short press the buttons to adjust the unit (um or mil). Short press the menu button to confirm the setting and enter the next setting item. Short press the power button to exit the setting interface and return to the normal measurement interface.

Operation of Other Setting Items

1. Higher Limit
   • When the LCD displays “SET” and “HI” symbols, it is in the higher limit setting state.
   • Short press the buttons to adjust the setting value upward/downward. Confirm with the menu button.
2. Lower Limit
   • When the LCD displays “SET” and “LO” symbols, it is in the lower limit setting state.
   • Same process as the higher limit.

Note:
If an error occurs, the LCD will display “Er” and return to the higher limit setting.

3. Probe Mode
   • The gauge has 3 probe modes:
     • Auto mode: Automatically identifies substrate type (ferromagnetic or non-ferromagnetic).
     • NFe mode: For non-ferromagnetic materials.
     • Fe mode: For ferromagnetic materials.

4. Continuous Measurement Mode
   • Toggle continuous measurement on/off with buttons.

5. Sound
   • Toggle sound on/off in the sound setting state.