Minitest 7400

High-end coating thickness gauge with a wide selection of external, interchangeable sensors.
The graphic display allows for direct display of statistical values, trend diagrams, histograms and simplified user guidance.
The MiniTest 7400 coating thickness gauge device enables measurement of non-magnetic coatings (paint, synthetic material, chromium etc.) on a ferromagnetic substrate (steel) and of insulating coatings (varnish, enamel, synthetic material etc.) on conductive substrates (aluminium, copper, stainless steel).
The MiniTest 7400 makes it possible to take a wide range of measurements, from the thinnest coatings in the sub-micrometer range (e.g. galvanised coatings), difficult geometries of the objects to be measured (e.g. measurement of steel pins, measurement to be taken in recesses and holes, etc.) down to thick coatings (e.g. flame retardant coatings in steel constructions, rubber coatings etc.).
The SIDSP sensors are technologically advanced and unique in their accuracy and reproducibility on account of their manufacturing process. Despite high accuracy the sensors are wear resistant and withstand even years of use on rough surfaces.
Measuring range and improved accuracy: the relationship between the electrical signal and the thickness measured is a complex relationship and must be linearized. Despite strict tolerances, each probe has slightly different characteristics. In analog devices, the linearization is done in the measuring unit with a limited number of points and cannot be 'customized' for each probe. In the SIDSP sensors, the linearization curve is stored in each probe and is automatically established during the manufacture of more than 50 points. During this calibration, it also stores changes due to the influence of the temperature for automatic compensation. There are thus not only more precise measures, but also sensors with higher ranges of measurement and resolution.
The MiniTest 7400 coating thickness gauge device is operated via a graphic interface and provides help functions akin to those of a PC: context-specific help, filing of readings in folder structures and menu-driven navigation with symbols and text display. The user guidance is available in 4 languages, others are under preparation.

Sensor type
F0,5 (HD)
N0,2 (HD)
F1.5, N0.7, FN1.5 (HD)
F1.5-90, N0.7-90, FN1.5-90
F2 HD
F5, N2.5, FN5 (HD)
N7
F15
F35
Properties
F
N
F
N
F
N
F
F
N
N
F
F
Measuring range
0 ... 0,5 m
0 ... 0,2 m
0…1,5 mm
0…0,7 mm
0…1,5 mm
0…0,7 mm
0…2 mm
0…5 mm
0…2,5 mm
0…7 mm
0…15 mm
0…35 mm
Field of application
Small samples, thin coatings, use with measuring stand
Small samples, thin coatings, use with measuring stand
Tubes and pipes or objects difficult to access
Rough surfaces
Standard sensors for a wide field of applications
Thick coatings, wall thickness
Thick coatings, wall thickness
Thick coatings, wall thickness  
Measuring principle
Magnetic induction
Eddy currents
Magnetic induction
Eddy currents
Magnetic induction
Eddy currents
Magnetic induction
Magnetic induction
Eddy currents
Eddy currents
Magnetic induction
Magnetic induction
Signal processing
Sensor-integrated 32 bits signal processing (SIDSP®)
Accuracy
± (1 μm + 0,75% of reading)
± (1,5 μm + 0,75% of reading)
± (5 μm + 0,75% of reading)
± (5 μm + 0,75% of reading)
± (20 μm + 0,75% of reading)
Repeatability
± (0,5 μm + 0,5% of reading)
± (0,8 μm + 0,5% of reading)
± (2,5 μm + 0,5% of reading)
± (2,5 μm + 0,5% of reading)
± (10 μm + 0,5% of reading)
Low range resolution
0,02 μm
0,05 μm
0,1 μm
1 μm
1 μm
5 μm
Minimum curvature radius convex
1,0 mm
1,0 mm
-
1,5 mm
15 mm
5 mm
50 mm
Minimum curvature radius concave
7,5 mm
7,5 mm
5 mm
10 mm
25 mm
25 mm
50 mm
Minimum measuring area
(without / with stand)
Ø14 / Ø5 mm
Ø14 / Ø5 mm
Ø14 mm
Ø14 mm
Ø14 / Ø10 mm
Ø23 / Ø20 mm
Ø25 / Ø25 mm
Ø100 mm
Minimum substrate thickness
0,3 mm
40 μm
0,3 mm
40 μm
0,3 mm
40 μm
0,5 mm
0,5 mm
40 μm
40 μm
1 mm
1,5 mm
Sortie câble
0/90°
0/90°
0/90°
0/90°
0/90°
0/90°
0/90°
0/90°
0/90°
Measuring rate in continuous mode
20 readings per second
Max. measuring rate in single readings mode
70 readings per minute