Moisture Measurement Of Building Materials; Air Humidity Measurement Using The Active Electrodes Rft - GANN Hydromette RTU 600 Betriebsanleitung

7.0 Operating Instructions for Moisture Measurement of Building Materials
Set selector switch (7) to position »B«. Connect selected measuring electrode to the meter socket (1) by
means of the measuring cable MK 8 and drive-in or stick-in electrode into the material to be measured. Press
measuring key (12) and read off result displayed by the LCD readout (3). Convert reading into per cent of
moisture by means of scale graphs listed at the end of this section.
7.1 Connection of the Electrodes
Different electrodes can be used with the meter depending on the material to be tested. The electrodes are
connected to the meter socket (1) by means of the measuring cable MK 8. On the meter side, this cable is
fitted with a BNC plug. Turn clockwise to lock it. To disconnect, turn notched fastening ring anticlockwise and
draw off plug. Do not use force and do not pull on the cable.
7.2 Testing Set Building Materials
For testing soft building materials, the drive-in electrode M 20 should be used, whereas hard building materials
such as concrete and cement flooring are to be measured with the stick-in electrode M 6 using contact paste.
7.2 Drive-in Electrode M 20
For penetration measurements, up to a depth of 70 mm, on soft, set building materials (gypsum, plaster, etc.),
drive electrode pins into the material to be tested (the electrode body is of impact resistant plastic). Take care
that both pins of the electrode are driven only into the material to be tested.
When withdrawing the electrode, the pins can be loosened by slight sideways rocking movements. The cap nuts
should be tightened by means of a spanner prior to a series of measurements. Loose pins may easily break.
7.3 Stick-in Electrode M 6
The two electrodes exclusively designed for moisture checks on set building materials are pressed, at approx.
10 cm apart, into the material to be tested. Both electrodes have to be inserted into the same type of build-
ing material. Also, the section to be measured must be coherent and not be crossed by an- other material. If
the material is too hard to press in the electrodes by hand (e.g. cement flooring, concrete, etc.) drill 6 mm
holes and fill them with contact paste. Then stick the pins into the contact paste.
7.3 Contact Paste
The contact paste is supplied in quantities of approx. 450 g in a plastic box sealed with a screw cap. It is used
to produce a good contact between the electrode point and the building material to be measured or to serve
as an extension to the electrode point. The moisture displaced by the drilling process is reconducted to the
material to be measured by the water contained in the highly conductive contact paste.
The surface of the material to be measured must not be smeared with the contact paste as the latter has a
high conductivity. When using the M 6 electrodes, it is advisable for an appropriate amount of the paste to be
rolled into a thin strand and pressed into the hole with the reverse end of the drill.
It is possible to keep the contact paste mouldable by adding normal tap water. The quantity contained in a
box is generally sufficient for approx. 50 measurements.
8.0 Instructions for Air Humidity Measurement using the active electrodes RFT 28
Set selector switch »X« (8) to position »M«. Connect electrode to the meter socket (2). Press measuring key
(12) and read off result displayed (in % R.H.) by the LCD readout (3).
8.1 Technical Specifications
Measuring range: 5 to 98 % R.H. for short periods.
For continuous or long period measurements in the range above 80 % R.H., a special calibration is required
for the measuring sensors.
Admissible operating temperature -10 °C to +60 °C for short periods,
for the meter and the electrodes: 0 °C to +50 °C for long periods.
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15.11.2006 Hydromette RTU 600 #013629