How to Use UNI-T UT343E Coating Thickness Gauge Correctly Malaysia

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Published: 1 October 2026

Correct probe placement, substrate selection and reference checking are essential when using the UNI-T UT343E Coating Thickness Gauge.

Even a good instrument may produce inconsistent results if the surface is dirty, the probe is tilted or measurements are taken too close to an edge. Following a consistent procedure improves repeatability during automotive, factory and coating inspections.

Step 1: Identify the Coating and Substrate

Before measuring, confirm what is beneath the coating.

The UT343E supports suitable coatings on:

Ferrous substrates: Steel, iron and other magnetic metals
Non-ferrous substrates: Aluminium, copper, zinc and other non-magnetic metals

The instrument is not intended for ordinary coating measurement on plastic, wood, rubber, glass, concrete or other surfaces without a compatible metal substrate.

If the coating-and-substrate combination is uncertain, confirm compatibility before relying on the results.

Step 2: Inspect the Probe

Check the probe before every inspection.

Look for:

Dust
Oil
Metal particles
Dried coating residue
Physical damage
Material stuck to the probe tip

Clean the probe carefully with a soft cloth. Do not scrape it with a sharp or abrasive object.

A contaminated or damaged probe can prevent proper contact and cause unstable measurements.

Step 3: Check the Gauge with Reference Plates

The UT343E is supplied with ferrous and non-ferrous reference plates and standard coating films.

Perform a basic check:

Select the plate that matches the intended substrate.
Measure the clean, uncoated reference plate.
Place a standard coating film on the plate.
Lower the probe vertically onto the film.
Repeat the measurement several times.
Confirm that the readings are stable and reasonable.

This is a functional reference check. It is not the same as a traceable calibration certificate.

Step 4: Clean the Measurement Surface

The test surface should be:

Clean
Dry
Free from dust
Free from oil and grease
Free from loose rust
Stable and fully cured

Contamination between the probe and coating may increase the apparent thickness or prevent a stable reading.

Avoid measuring immediately after washing the component unless the surface is completely dry.

Step 5: Select Automatic or Manual Substrate Mode

Automatic mode is convenient when inspecting different metal substrates.

Manual mode may provide a more consistent workflow when the operator already knows that every component in the batch uses the same substrate.

Select:

Ferrous mode for suitable coatings on steel or iron
Non-ferrous mode for suitable coatings on aluminium or other compatible non-magnetic metals

If automatic identification changes unexpectedly, confirm the substrate and repeat the measurement using manual selection.

Step 6: Hold the Probe Perpendicular

Place the probe flat and perpendicular to the test surface.

Use the following movement:

Hold the instrument steadily.
Lower the probe vertically.
Allow the measurement to complete.
Lift the probe away from the surface.
Move to the next inspection point.

Do not tilt the probe or drag it across the coating.

Angled contact may produce inconsistent results and can mark a delicate surface.

Step 7: Avoid Unsuitable Measurement Areas

Whenever possible, avoid measuring:

Too close to an edge
Beside a hole
Directly on a sharp corner
On a strongly curved surface
Over weld spatter
On a very rough surface
Over decals or protective film
On loose or damaged coating

Component shape and surface condition can influence the reading.

If an edge or curved area is important to the inspection, take several readings and compare them with equivalent locations.

Step 8: Take Multiple Readings

Do not judge the complete component from one measurement.

Take readings from:

Different sides
Flat centre areas
Edges and corners
Recessed sections
Areas near welds
Locations important to corrosion protection
Positions specified by the customer or drawing

Review the minimum, maximum and average values to understand coating consistency.

A satisfactory average should not be used to ignore an individual reading below a critical minimum requirement.

Step 9: Use Single or Continuous Mode Correctly

Use single measurement mode when each inspection point must be recorded separately.

This is suitable for:

Quality-control checklists
Supplier inspection
Vehicle-panel comparison
Specific drawing locations

Use continuous measurement mode when checking variation across a larger area or taking several readings quickly.

Keep the probe movement controlled and lift it between points unless the operating procedure specifies otherwise.

Step 10: Set the Correct Limits

Enter upper and lower limits only after confirming the approved coating specification.

The LED and audio alarm can help identify readings outside the selected range.

Limit values may come from:

Engineering drawings
Customer specifications
Internal quality standards
Coating supplier recommendations
Approved reference samples
Inspection procedures

Do not use arbitrary limits for product acceptance.

Step 11: Save and Review the Data

The UT343E can store up to 3300 readings and supports Bluetooth App and PC data analysis.

Record enough information to identify:

Product or vehicle
Supplier or customer
Batch number
Coating type
Substrate material
Measurement location
Acceptance limits
Inspection date

Digital data is more useful when each reading can be connected to a specific component and location.

Common UT343E Operating Mistakes

Avoid these common mistakes:

Measuring without checking the reference plate
Using the wrong substrate mode
Holding the probe at an angle
Taking only one reading
Measuring a dirty or wet surface
Testing too close to an edge
Comparing readings from different locations
Measuring plastic components
Assuming every different reading means the gauge is faulty
Treating a reference check as formal calibration

A consistent procedure is as important as the instrument specification.

When Should You Stop Using the Gauge?

Stop using the UT343E for acceptance decisions if:

It repeatedly fails the reference check
Readings remain unstable on a clean reference plate
The probe is damaged
The instrument cannot identify the substrate
It was dropped or exposed to water
The results differ significantly from a verified reference
An error remains after restarting

The gauge should be inspected before it is returned to quality-control use.

UT343E Support in Malaysia

The UNI-T UT343E is suitable for automotive inspection, powder coating, metal fabrication and incoming quality control in Selangor, Kuala Lumpur, Johor and Penang.

For product availability or assistance selecting a suitable coating thickness gauge, contact MTM Precision with your coating type, substrate material and expected measurement range.

MTM Precision Sdn Bhd
Showroom & Service Centre: No. 29-1 & 29-2, Jalan Bandar 18, Pusat Bandar Puchong, 47160 Puchong, Selangor, Malaysia
Tel: 03-8080 7172
WhatsApp: +6016-660 7346
Email: mtmpre@yahoo.com
Website: www.mtmpre.com.my

How to Use UNI-T UT343E Coating Thickness Gauge Correctly Malaysia