MMP20 SONO-DIS (option D)
Hauser
Page 17
To start measuring, briefly press the "Start measurement" key
. The device starts measuring
and a rotating
symbol appears in place of the battery in the top right-hand corner for the
duration of the measurement process. No other actions can be performed during this time. A single
measurement takes around 2-3 seconds. Once the measurement is finished, the battery symbol
appears on the display again. The
water content
, calculated using the raw density D, is displayed
in
l/m
3
. The number of individual measurements
"No. values"
is displayed below this value.
To obtain a representative value for the material mix, it is advisable to take at least 5 individual
measurements as described under the section "Measurement of laboratory samples in a bucket".
In the case of concretes that tend to bleed, we strongly recommend taking a higher number
of individual measurements, as this increases the accuracy and makes for a more
representative value!
Note: Incorrectly mixed concretes are difficult to measure with the SONO-WZ!
An evaluation of the quality of the measurement:
The standard deviation
StdDev
displayed by the SONO-DIS is a reflection of the quality of the
reading. The
StdDev
provides information about the quality of the measurement. If the
StdDev
value is greater than 0.5, the concrete mix is so heterogeneous that it is recommended to take more
individual measurements. At least 6 single measurements should be taken and a
StdDev
of 0.1 to
0.5 should be displayed before you should stop taking single measurements and accept the
measured value as the final result. It must be noted that it is very difficult to achieve a
StdDev
less
than 0.5 for very heterogeneous concretes (e.g. concretes that bleed a lot).
Smileys on the display screen indicate whether the standard deviation is good (<0.2), acceptable
(0.2 to 0.49) or not acceptable (>0.5).
SONO-DIS automatically filters out water content values that are less than 100 liters. This can
happen, for example, if the start button is accidentally pressed during a measurement series or if
the probe was not yet fully introduced into the concrete. As they are too low (<100 liters), these
values are flagged with a warning sign
and are not used to calculate the average!
The measurement series can be cleared by pressing the
key and the SONO-DIS is then ready for
a new measuring cycle.
