Figure 19: The Calc Mode Calculation - Hydronix Hydro-Control VI Operator's Manual

Using Moisture Control
Optimising CALC Mode
2.9
CALC Mode works by taking one average value at the end of the Dry Mix, and a second average
value at the end of the Wet Mix. Using these two values and the percentage moisture change
between the two points (this is the quantity of water added divided by the batch weight) it is
possible to calculate the quantity of water that is needed to get from any other start point to the
target moisture value.
Mixer
Loading
Moisture
B
A
Moisture
B
A
C
As the diagrams in Figure 19 show, if it takes 'x' litres to get from moisture point A to moisture
point B then, as the sensor unscaled value is linear with moisture, a calibration line can be
obtained that can then be used to calculate the amount of water needed to get from any new
moisture point to the target value, B. In the diagram example it takes 'xx' litres to get from point
C to the target.
The real moisture percentage values are not required for this calculation as it relies only on the
change in the unscaled values. In order to achieve an accurate calibration the following values
must be known:
Batch weight
•
Quantity of water added
•
An accurate Dry Mix sensor reading
•
• An accurate Wet Mix sensor reading (which also gives the target value)
46 Hydro-Control VI Operators Guide HD0456 Rev 1.7.1
Main Water
Dry Mix Time
Addition
'x' litres
'xx' litres

Figure 19: The CALC Mode Calculation

Wet Mix
Discharge
Time
Chapter 8
Time
Water
Added