7
Humidity measuring unit CMG 100
Inserting and replacing batteries
The humidity measuring unit is
powered by a 9 V block battery.
When delivered, the battery
is enclosed separately. It must
be inserted into the humidity
measuring unit.
To insert the battery, proceed as
follows:
•
Using a suitable screwdriver,
remove the battery compartment
cover from the back of the
measuring unit
•
Insert a new 9 V block battery
into the battery compartment [8],
observing the correct polarity.
Make sure that the contacts of
the unit are well seated
•
Replace the battery compartment
cover and screw it back in place
•
Replace the battery when the low
battery indicator [9] lights up on
the LC display
•
To change the battery, proceed
as described above. However,
remove the used battery from
the contacts and the battery
compartment before inserting a
new one.
7.0 Commissioning
NOTE
Ensure that the humidity
measuring unit is switched off
before changing the battery.
General notes before starting
measuring
•
The displayed humidity level is
an average value determined by
the moisture on the outer surface
as well as inside the material.
If there is any visible surface
moisture or water, wipe it off
and allow the surface to dry for
a few minutes before starting
the measurement
•
Other factors can also influence
the measurement. Before the
measurement, the corresponding
surface must be cleaned of any
paint residues, dust, etc
•
Before measurement, the
measuring point must be cleared
of impurities (e.g. dust and other
loose components).
•
If the measured material contains
metal (e.g. nails, screws, leads,
pipes, etc.) and this is located in
the measuring field of the sensor,
the measured value increases
abruptly due to strong reflections
•
If the spherical head is held in
corners (e.g. tile joints or window
niches), the measured value is
generally higher because there is
more substance in the scattering
field of the measuring head
•
There must be a distance of more
than 8 to 10 cm from the corner
•
Hold the measuring unit at its
outermost end as far away as
possible from the ball head of
the humidity sensor [1] to avoid a
possible influence of humidity by
your hand on the measured value
8.0 Use
•
The measuring unit is not suitable
for measuring metal or other
highly conductive materials.
If there is metal enclosed in
the material (e.g. nails, screws,
cables, pipes, etc.) in the sensor's
measuring range, the measured
values increase considerably
•
If the humidity sensor [1] is
placed in a corner of the wall,
the measured values may be
higher because there are two or
three surfaces in the measuring
range.
Keep a minimum distance of 8
to 10 cm from other surfaces to
avoid interference
•
Place the humidity sensor [1] on
smooth surfaces. Rough surfaces
lead to inaccurate measurement
results
•
The measuring depth of the
unit ranges from 20 to 40 mm.
Depending on the density of
the material, a measurement
of the inner core may not be
possible. If the material is less
than 2 cm thick, the measured
value of the humidity level may
be inaccurate due to adjacent
material
•
The humidity sensor [1] must be
held at right angles directly to
the surface to be measured
•
The density of the measured
material plays an important role
for the measurement result.
The measured value increases
with the respective density
•
An important area of application
for this unit is comparative
measurements, where the
measured value is compared with
a reference value. The reference
value is determined by
