Vaisala HM44 - Manual (Page 18)

User's Guide _______________________________________________________________________
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Preparations for the measurements
The holes shall be drilled 3 days before the measurements. A plastic sleeve and an installation
cover are placed to the hole immediately after drilling. A probe can be placed to the plastic
sleeve immediately after drilling or before measurements. Follow the instructions below.
1. Bore 3 days before the measurements at least two holes with diameter of
∅ 16 mm and
sufficient depth, see page 13. Clean the hole thoroughly e.g. by blowing air or with a
vacuum cleaner.
2. Press a plastic sleeve into the hole. If you need something to press it with, use e.g. the
lid of the installation cover.
Figure 5.1 Pressing the sleeve into the hole
NOTE Make sure that the sleeve and the probe are not colder than the
concrete during installation: this might cause condensation on the
probe and the readings can be incorrect.
3. Close the hole by using an installation cover as described in the following or Press an
installation cover on the plastic sleeve and make it slide down freely. Press the installation
cover against the base so that the sealing presses down slightly. Turn the cover 90° to lock
it in place.
Figure 5.2.Locking the
cover in place