CARSYS DPM-816 PRO and COMBO gauges — the full manual

Dear owner of the coating thickness gauge (hereinafter the gauge), congratulations on your purchase. The gauge is designed and made in Russia. We are sure it will serve you well for a long time. For correct use, please read this manual carefully.

This model has the following features:

• Measures coating thickness over ferrous, galvanised ferrous and non-ferrous metals.
• Measures on convex and concave surfaces.
• Zinc and ferromagnetic filler detector.
• Thickness comparison mode.
• Wide measuring range from 0 to 3500 µm.
• Readings in millimetres, micrometres and mils.
• Wide operating temperature range −25…40 °C.
• Automatic calibration adjustment.
• Informative backlit LCD display.
• Probe contact-force stabilisation.
• Automatic substrate-type recognition.
• Automatic and manual selection of the measuring method.
• Magnetic-induction and eddy-current methods.
• Power: one 1.5 V “LR03/AAA” cell.
• Low-battery indicator.
• Compact, convenient size.
• Automatic power and backlight off.
• Single and continuous measurement.
• Smart thickness calibration of up to 8 points stored in non-volatile memory.
• Simple, intuitive three-button control.
• A dedicated sound for each measuring method and for button presses.
• Complies with industry standards.
• A 3-year factory warranty.

The gauge is designed to measure coating thickness:

By the magnetic-induction method — the thickness of various dielectric coatings (paint, plastic, primer, including those with non-magnetic metal powders, etc.) and conductive non-magnetic coatings (aluminium, zinc, chrome, copper) over ferrous substrates (steel, iron).

By the eddy-current method — the thickness of various dielectric coatings (paint, plastic, primer, etc.) over non-ferrous substrates (aluminium, zinc, copper, etc.).

Use. Inspecting a car body to assess its condition — for example, when buying a car, before paintless dent repair or scratch removal. Quality control of painting or other protective coatings in service centres and production.

The gauge is a precision instrument. Avoid dropping it and mechanical impacts.

The gauge is water-resistant but not fully waterproof; it must not be used underwater or in heavy rain. If water accidentally gets on the gauge, wipe the drops with a soft dry cloth.

Do not use the gauge near sources of strong radio waves or magnetic fields — they can affect its operation and measurement accuracy.

Do not leave the gauge in hot places, for example a car standing in the sun. Do not disassemble the gauge.

When moving the gauge from cold to a warm room, condensation may form on the case and internal parts. To avoid condensation, first put the gauge in a plastic bag. Before taking it out, wait until it warms up. If condensation forms, do not use the gauge until all the condensation has evaporated.

Cleaning. To remove dust from the case or probe, use a soft dry cloth. Do not use cleaning agents containing organic solvents.

Storage. Keep the gauge away from direct sunlight in a heated dry room. Do not leave the cell inside the gauge during long storage. Do not keep the gauge near devices generating strong magnetic fields, such as magnets, power supplies or electric motors. Do not store it in hot, dusty or damp rooms, or where corrosive chemicals are present.

Display. The gauge has an LCD with an auto-off backlight, showing the coating thickness, mode, method, units and other parameters. Although the display uses FSTN technology with a wide operating temperature range, at low and high temperatures the image may refresh more slowly.

Sound. The gauge has a dedicated sound for each measuring method, so during measurement you can tell at once from the sound which substrate (metal) is under the coating.

Probe. To improve accuracy and to measure on convex and concave surfaces, the gauge uses a probe designed to stabilise the contact force of its sensitive part against the surface, with a spherical sensing tip. The sensitive part is made of heat-treated high-strength steel.

Do not apply mechanical force to the probe. Do not try to remove the probe from the device or rotate it — this may impair correct operation.

The gauge is controlled by three buttons, each with several functions via a short press or a hold:

• “MODE” — switches the measurement mode; increases the thickness during calibration; enters thickness calibration; starts the 6-point calibration for ferrous metals.
• “ON/OFF” — turns the gauge on/off; turns the backlight on/off; exits thickness calibration.
• “UNIT” — selects the units; decreases the thickness during calibration; resets the thickness settings; toggles thickness comparison; starts the 6-point calibration for non-ferrous metals.

First make sure the kit includes all the components listed below:

• The coating thickness gauge.
• Aluminium and steel calibration bases.
• Two reference plastic calibration plates.
• An insert with a QR code and a link to this user manual.

To start, install one alkaline 1.5 V “LR03/AAA” cell.

Before first use, after a long period of not using the gauge, and to improve accuracy, check the measurement accuracy and, if needed, run the thickness calibration.

Installing the cell. Open the battery cover by sliding it with your thumb in the direction of the arrow.

Insert the cell into the compartment observing polarity. The gauge will display the serial number in groups of 4 characters. Close the battery cover until it clicks.

When the gauge ships with a cell, the battery is installed with an insulating film tab. Remove the film by pulling the protruding end.

Low-battery indicator. The gauge uses very little power and, without the backlight, can run on one battery for a very long time. When the cell is low, a low-battery icon appears in the top-right of the display.

Do not use the gauge with a flat cell. Do not leave the gauge in long storage with cells inside — over time the cells may deteriorate, leak electrolyte and damage the gauge.

Turning on. To turn on, press and hold “ON/OFF” for 2 seconds until it beeps.

After powering on, the gauge auto-calibrates for 2 seconds, adjusting the probe to the environment. Until auto-calibration finishes, keep the gauge away from metal objects and strong magnetic fields. After 2–3 seconds dashes appear on the display, meaning the gauge is in measurement mode and ready.

Turning off. To turn off from any state, press and hold “ON/OFF” for 2 seconds. After 2 minutes of inactivity the gauge turns off automatically to save the battery.

Backlight. The backlight lets you use the gauge in the dark. To toggle it, press “ON/OFF”. After 1 minute of inactivity the backlight turns off automatically to save the battery.

The gauge has 5 measurement modes: “A”, “M”, “P”, “F”, “N”. To switch, press “MODE” briefly — the modes cycle. The current mode is shown on the display.

• “A” — a single automatic measurement with substrate recognition and the magnetic-filler and zinc detectors. Ferrous “Fe”, non-ferrous “NFe”, ferrous coated with non-ferrous “FeNFe” (zinc). If magnetic filler is detected, a triple warning beep sounds. The gauge automatically uses the right method. The metal type is shown on the display. Ideal for checking a car body.
• “M” — detailed measurement. Works like mode “A” but with higher resolution across the whole range.
• “P” — industrial mode. Works like mode “M” but uses a 6-point user calibration map. To use it, you must run the 6-point calibration. Intended for cases where you need to switch quickly between calibration maps for different metals.
• “F” — fast continuous measurement (8 per second) of coating thickness over ferrous metals by magnetic induction. Suits curved surfaces.
• “N” — fast continuous measurement (8 per second) of coating thickness over aluminium alloys by eddy current. Suits curved surfaces and pipes.

For convenience the gauge can show results in several units: millimetre (mm), mil, micrometre (µm). 1 mm = 1000 µm. 1 mil = 25.4 µm.

Units are selected by short successive presses of “UNIT”, cycling through the units. The choice is shown in the bottom-right of the display.

Turn on the gauge (see “Turning on”) and wait for auto-calibration to finish. When it finishes (2–3 seconds), dashes are shown on the display. If needed, choose the mode and units. Mode “A” is on by default.

Measuring in modes “A”, “M”, “P” (automatic modes). Place the probe firmly and squarely on the surface. Do not move the gauge during measurement (until it beeps), otherwise the reading may be wrong.

As soon as the gauge detects the probe is still on the surface, you hear a beep marking the end of the measurement. Lift the gauge at least 5 cm from the surface. For 30 seconds the display shows the result — the coating thickness, the substrate type and the units. “Fe” — ferrous, “NFe” — non-ferrous, “FeNFe” — zinc over ferrous.

Accuracy depends on how flat and firmly the probe sits on the surface. Do not move the gauge during measurement until the beep. If you use the kit plates for measuring or calibrating, because of their small area, measure at the very centre of the plates to avoid the edge effect.

Measuring in modes “F”, “N” (continuous). In these modes the gauge measures fast and continuously. Place the probe on the surface — the gauge immediately and continuously (8 times per second) shows the result. This mode helps when it is hard to hold the gauge still, for example on pipes and concave or convex surfaces.

How comparison works. You measure an area of coating (e.g. a car roof) that is taken as the reference. Then, when measuring, the gauge shows how much thicker or thinner the reading is than the reference.

Taking the reference. Measure the coating you want as the reference. When the result is shown, press and hold “UNIT” for 2 seconds. The display shows “CAL”, meaning the reference was taken successfully. Now thickness is shown as a comparison with the reference. The reference is taken separately for ferrous and non-ferrous metal.

Turning comparison off. There are 3 ways: 1 — turn the gauge off and on; 2 — enter thickness calibration; 3 — clear the thickness settings.

This function fully removes all previous thickness settings (calibrations) for ferrous and non-ferrous metals and disables the comparison mode.

It restores the gauge in case of a wrong calibration, but for accurate measurement you will need to calibrate again.

To clear the thickness settings, while dashes are shown press and hold “UNIT” for 3 seconds. The display shows “CL” and a beep sounds. The thickness settings (calibrations) are removed.

For accurate thickness measurement the gauge needs calibrating to your conditions. The gauge keeps the calibration for a long time, and if conditions have not changed it does not need re-doing each time.

For ideally accurate measurement, calibrate the gauge on a metal base as close as possible to what you measure (material, shape, size, surface roughness).

The gauge has 2 independent calibration maps for ferrous and non-ferrous metals. The 1st, base factory calibration is used by modes “A”, “M”, “F”, “N”. The 2nd works in mode “P” and uses a 6-point thickness calibration, letting you switch calibration quickly just by changing mode.

When calibrating, keep it clean, as the tiniest speck between the reference plate and the metal base can shift the result by 5–10 µm.

Smart calibration. When to calibrate: on first use for your needs; if the gauge has not been used for a long time; before measuring for maximum accuracy.

Calibration procedure. To enter thickness calibration, press and hold “MODE” for 2 seconds until “F-0” appears on the display.

Measure on a bare metal base or with a reference plate of known thickness within 0 to 3500 µm. For example 0, 100 or 1000 µm. Repeat if needed. While the result is shown, use “MODE” and “UNIT” to set the thickness of the coating being measured on the display. Measure again to check and adjust once more if needed. Repeat until you get the right results.

If during calibration the readings are sometimes higher, sometimes lower, it means each measurement is done differently: different spots (not the centre of the plates), tilt, or movement of the gauge and plates during measurement, etc.

The gauge can store from 1 to 8 points of different thickness. This number covers any need, and you choose how many points and of what thickness to calibrate. The gauge picks the optimal use of the points itself. It is best to calibrate at least two or three thickness points. For example 0 and 100 µm, 0 and 1000 µm, or 0, 100 and 1000 µm — this covers the whole measuring range.

Settings are saved and removed automatically. The gauge analyses the current thickness settings and adjusts the probe.

Exiting calibration. Press “ON/OFF” twice to exit calibration and go to measurement mode. The display shows “8888” for 1 second and the gauge enters measurement mode.

The gauge is factory-calibrated for substrates of ANSI430 steel (magnetic-induction method) and AMG2 aluminium alloy (eddy-current method).

Used in measurement mode “P” and needed when measuring coatings on substrates whose properties differ from the standard ones and where fast switching between calibrations is required. In a new gauge this calibration is identical to the factory one. Calibration requires a metal base and 5 calibration plates of known thickness (not included). All calibration points must be evenly spread across the whole measuring range from 0 to 3500 µm.

Entering calibration. Turn the gauge off. Then press and hold “MODE” to enter calibration for a ferrous base (magnetic-induction method) or “UNIT” for a non-ferrous base (eddy-current method) until “FCAL” or “ACAL” respectively appears. Wait for the digit “0”, the zero calibration point — from then you can start calibrating.

Calibration process. First point “0”. Measure the bare metal base for which you are calibrating. Repeat if needed. Press “ON/OFF” briefly to save the result and move to the next point. The display shows “F-1” — the next point, and the gauge shows the recommended plate thickness for this point.

Measure the metal base with a reference plate on it. Repeat if needed. Use “MODE” and “UNIT” to set the thickness of the measured plate and press “ON/OFF” to move to the next point.

Repeat for each calibration point. After saving the last point the display shows “8888” and the gauge enters measurement mode “P”. In a new gauge the 6-point calibration matches the factory one.

Magnetic (metallic) filler is a filler made specifically to fool thickness gauges. It consists of fine iron powder mixed with a binder. Using magnetic filler distorts the reading, and the gauge shows a thickness of roughly 1–2 layers of paint.

Detection is based on differences in how eddy currents pass through ferrous metal and iron powder. If the reading is below 1000 µm, the gauge runs a magnetic-filler check and, if detected, gives three warning beeps. If the reading is 1000 µm or more, there is no point detecting magnetic filler, since 500 µm and above already indicates filler.

This function is useful for comparing car body panels. For example, if the original factory panel is galvanised but a repaired one is not. You can measure all body panels and confirm the left side matches the right.

Detection is based on using eddy currents to find non-ferrous metal applied over ferrous metal and measuring the relative conductivity of the surface. Aluminium or copper have higher conductivity, zinc lower. Analysing these parameters, the gauge can detect galvanising.

If the reading is below 1000 µm, the gauge runs a zinc check and, if detected, shows the “FeNFe” indicator. If the reading is 1000 µm or more, detecting zinc is pointless, since 500 µm and above already indicates filler and repair. The zinc sensitivity is set to an optimal level, giving maximum sensitivity with minimum false triggers. Unlike many others, the gauge does not read ferrous metal coated with aluminium or copper as galvanising.

The zinc detector relies on the gauge’s thickness settings for ferrous (steel) and non-ferrous (aluminium alloy) metal. So if the thickness settings are off or set for another metal, the detector may misbehave.

You can find repainted spots by taking point readings on the parts of the body most prone to damage. Every car is factory-painted in an automated process, and the paint thickness is relatively constant, but it can differ somewhat between makers and from batch to batch.

Usually the car’s coating thickness is 80–200 µm. On one car the spread between panels should not exceed 20%.

If on one or more panels the reading exceeds the average of the others by 2 times, this indicates a second coat of paint. If it exceeds the average by more than 2 times, the panel was prepared with filler. The thicker the paint layer, the poorer the bodywork.

• Factory paint on most cars is no more than 200 µm. Signs of repair are a layer that is either thicker or thinner.
• Repainted panels are on average 50–100 µm thicker. With a “paint-to-beat-the-gauge” job the thickness stays near factory (if there is no filler), but there is usually a patch with filler.
• Sharp jumps in paint thickness (from 50 µm) between adjacent points (up to 2 cm) indicate filler over dented metal.
• All cars are painted symmetrically. If in doubt about a left door, compare it with the right. Sharp differences in paint thickness from one door to another most likely indicate a respray of the panel.
• The evenness of factory paint depends on the model: some cars are painted evenly (±20 µm within a panel), some less so (±30 µm within a panel).
• Paint in door apertures is often much thinner than on the outside of the body.
• Protective and decorative films have an even thickness, which lets you check paint thickness under the film too, allowing 100–150 µm for the film.
• Check roof pillars in small steps (every 5 cm) so as not to miss filler on the seams.
• Do not trust paint-thickness tables — better take the roof as a reference.
• Zinc detection can sometimes reveal a replaced original panel. Cars are not always galvanised entirely — often only the parts prone to corrosion are (sills, wings, doors).
• Cataphoresis and so-called “cold galvanising” are not galvanising — they are just a special anti-corrosion primer with added zinc.

It is recommended to hold the gauge closer to the probe — it is then easier to place it flat and square on the surface, and the gauge does not shake in your hand.

When measuring on the reference plates, hold the plates in your left hand and the gauge in your right. A common mistake is putting the plates on a table and measuring: you cannot place the gauge flat, and the plates shift with each measurement.

When measuring on an orange-peel surface, note that the height difference of the orange peel increases the error due to the uneven coating thickness. The probe lands on different parts of the orange peel with different thickness. In this case take several readings and average them.

The specification is general; individual units may differ and may be changed by the maker without notice.

If the gauge behaves unexpectedly, check the table below first.

The maker guarantees free repair of defects arising through its fault within the warranty period, provided all warranty, storage and operating conditions are met.

The warranty does not cover gauges: with broken seals, signs of corrosion or opening (self-repair), dirt, insects or foreign objects; with mechanical, electrical (smoke, short-circuit marks, liquid spills) or other damage from misuse or transport, or natural wear; or where the serial number on the warranty card (receipt) does not match the gauge.

It also does not cover gauges without a warranty card or receipt confirming the date and place of purchase, the seller’s name and the serial number (the warranty then counts from the date of manufacture). Warranty repair and service is carried out by the maker via the authorised dealer that sold the gauge. The buyer may send the gauge directly to the maker for repair without the seller — in this case the warranty repair is free, and delivery to the repair point is at the buyer’s expense.

The warranty for the “CARSYS DPM-816 PRO” is set at 3 years from the date of purchase. Full details at car-sys.com. Designed and made by: IE V. N. Chuvakin, Omsk, Russia.