Endress+Hauser Solitrend MMP20, Руководство по эксплуатации

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Commissioning fresh concrete measurement Solitrend MMP20 (Option D)
34 Hauser
1. Make sure that no air is trapped in the fresh concrete
2. Press the Enter key to "Start measurement". The water content, determined using
the raw density, is calculated in l/m 3 and displayed. "No. values" indicates the number
of individual measurements that have been taken.
 The first individual measurement is taken and indicated on the screen by a
rotating symbol . The measurement takes approx. 2 s.
 18 The Meas menu
1 Set new parameters
2 Pressed briefly: delete last individual measurement value; pressed for longer: delete entire measurement
series
3 Conductivity / assessment of the cement
4 Standard deviation: more single measurements are needed if the std-dev is > 0.5 !
5 Remaining battery
6 Water content as an average value
7 Last single measurement (can be deleted)
8 Number of measurements performed
• To obtain a representative value for the material mix, take at least 5 individual
measurements (see Measurement cycle for SWZ probe).
• In the case of concretes that tend to bleed, taking a higher number of individual
measurements increases the accuracy and ensures a more representative value.
• Large gravel pieces directly at the surface of the probe can affect a reading; a lower
water content is measured, for example.
• Incorrectly mixed concretes are difficult to measure with the probe.
Measurement quality:
The standard deviation StdDev displayed by the handheld device reflects the quality of the
reading. If the StdDev value is >0.5, the concrete mix is too heterogeneous; more single
measurements are required. At least 6 single measurements should be taken and a StdDev
of 0.1 to 0.5 should be displayed before you can stop taking single measurements and
accept the measured value as the final result.
It is very difficult, however, to achieve a StdDev of <0.5 for very heterogeneous concrete
(e.g. concrete that bleeds significantly).
Smileys on the display screen indicate whether the standard deviation is good, acceptable
or not acceptable:
• good (<0.2)
• acceptable (0.2 to 0.49)
• not acceptable (>0.5)
The handheld device automatically filters out water content values that are less than
100 l/m
3
. 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.
Values that are too low are flagged with a warning sign and are not used to calculate
the average.
The measurement series can be cleared by pressing the navigation key and the
handheld device is then ready for a new measuring cycle.