LaserLiner MultiWet-Master Manual De Instrucciones página 19

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Material table - capacitive measurement
Softwood low-density woods: e.g. spruce, pine, limewood, poplar, cedar, mahogany
Hardwood higher-density woods: e.g. beech, oak, ash, birch
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Application notices
– place the conducting contacts completely on the material to be measured, pressing them down evenly
and lightly to achieve good contact
– measured surface should be free of dust and dirt
– keep at least a 5 cm distance from metal objects
– metal pipes, electric lines and reinforcing steel can falsify measurement results
– make measurements at several locations on the surface
13
Determining material moisture
Due to the differing constitution and composition of materials, specific application notices are to be
followed for their moisture assessment:
Wood: The measurement should be made with the length of the device in parallel with the grain of
the wood. The measured depth in wood is 30 mm maximum but does vary somewhat with differing
wood densities. Measurements made on thin wood boards should, if possible, be made on a stack of
these boards as otherwise the measurement will be too low. Measurements made on installed wooden
structures are influenced by the structural conditions and their chemical treatments (e.g. paints) with
various materials. Thus such measurements should only be viewed relatively. Nevertheless, the differences
in moisture distribution are very good for localising moist places as an indication of damage, e.g. in
insulation.
Greatest accuracy is reached between 6 % and 30 % material moisture. In very dry wood (< 6 %)
irregular moisture distribution can be detected, in very wet wood (> 30 %) saturation of the wood
bres begins. Material relative moisture reference values, in %, for use with wood:
– Outdoor usage:
– Use in unheated rooms:
– In heated rooms (12 °C ... 21 °C):
– In heated rooms (> 21 °C):
Example: 100% material moisture for 1 kg of wet wood = 500 g water.
12 % ... 19 %
12 % ... 16 %
9 % ... 13 %
6 % ... 10 %
MultiWet-Master
GB 19