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mvip@mitech-ndt.com
2.7 Measuring conditions
In order to avoid erroneous measurements:
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Make sure that no heat or surface deformations occur at the testing point during the testing process.
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Ensure the surface of the workpiece is clean, smooth and dry.
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Ensure that the specimen is immobile and not subject to vibrations during the test (due to the
dynamic functioning of the hardness testing method). Thin parts must be specially fastened.
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Use samples with large dimensions and enough mass if possible. Special measures must be taken
for specimens that weigh less than 5 kg.
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Recommendation: Carry out at least 3 to 5 impacts at spaces of at least 3 to 5 mm at each
measuring point and use the average of the individual values.
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Do not carry out an impact in an area that has already been deformed by another impact.
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When preparing the surface, please observe that the condition of the material may be affected (e.g.
due to heating or cold working). As a consequence, the hardness is also influenced. If the surface is
inadequately prepared, the measuring results can be affected. Excessive surface roughness results
in lower HL values (the true hardness is greater than indicated) and broad variations of individual
measurements. Cold-worked surfaces produce excessively large HL values (the actual hardness is
less than measured).
3 Startup
3.1 Power supply
Two AA size alkaline batteries are needed as the power supply.
The battery compartment is situated at the instrument back. The cover is fastened with two screws. To
insert the batteries:
Loosen the two screws of the battery cover.
Lift the cover off upward.
Insert the batteries into the battery compartment.
Close the battery compartment and fasten the screws.
Turn on the instrument to make sure the battery is installed correctly and firmly.
3.2 Connecting the instruments
To prepare the instrument for operation, you have to connect an impact device to it. The instrument is
available with the Lemo socket connectors.
When connecting an impact device to the instrument, it’s not only important that the physical connection
be properly made. It’s also important that the instrument is properly configured to work with the installed
impact device.
3.3 Starting the instrument
To start the instrument, press down
key until display activates. While the device is booting a splash
screen, the serial number of the unit, the installed software version, the date and time of the system
appear on the display.
The start display of the instrument appears as
right figure.
Press F1 key to change to a different language.
Press F3 key to skip the booting check process
and enter the measure mode immediately.
