GANN HYDROMETTE HB 30, Operating Instructions Manual

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Deep Electrode M 21-100/250
These two electrodes, exclusively designed for the measurement of set building materials, al-
low a measuring depth of up to 100 mm or 250 mm respectively. Insulated sleeves prevent
the results from being distorted by a high degree of surface moisture such as dew or rain.
Drill two 8 or 10 mm dia. blind holes approx. 10 cm apart (the section to be measured must
be coherent and consist of the same material).
It is very important that a sharp drill is used at low speed. Where a lot of heat is generated in
the hole, it is necessary to wait at least 10 minutes before introducing the electrodes or con-
tact paste. Insert the tube point 30 mm vertically into the contact paste in order to fill it with
paste. Clean the outside of the electrode tube right to the point and insert into blind hole.
Prepare the second hole in the same way. Connect measuring cable to the electrode rod and
insert the latter into the electrode tube. Press the contact paste to the end of the hole by ex-
erting pressure with the rod. Connect the measuring cable to the meter, press measuring key
and read off result.
The readings may under some circumstances be distorted if there is too much
contact material in the electrode tube or if an electrode tube contaminated with
contact paste is repeatedly removed and inserted.
Contact Paste