Aqua DGTEC CD, Instruction And Maintenance Manual

Page: 12 / 36

ADSP7000634 rev. 1.3 23/09/2020 12/36

Read conductivity :1% - 65% Set-point value

Flow Rate Percentage = 100 * (Nominal Flow Rate/
Effective Flow Rate);

Read conductivity :65% - 90% Set-point value

Flow Rate Percentage = 80 * (Nominal Flow Rate/
Effective Flow Rate);

Read conductivity :90% - 110% (hysteresis) Set-point value

Flow Rate Percentage = 80 * (Nominal
Flow Rate/ Effective Flow Rate) if the conductivity value is nearing the set-point in the indicated range;
Flow Rate Percentage = 0% (non-active dose), if the conductivity value is decreasing in the indicated
range;
The Nominal Flow Rate is the flow rate indicated on the pump label, while the Effective Flow Rate value is obtained
by means of pump calibration, which enables the correction of variations on the nominal flow rate due to multiple
factors (wear of the peristaltic tube, etc).
If, from calculations on the Flow Rate Percentage value, a value greater than 100% of the pump Flow
Rate is obtained, you must consider that maximum value as equivalent to 100% of the effective flow
rate (or nominal, if pump calibration has never been executed).
DOSING SOLID DETERGENT (SOLENOID VALVE)
If the peristaltic pump is not used and the 24V solenoid valve is piloted to pass water into the solid detergent
dispenser, dosing regulation will occur at the time of opening and closing of the solenoid valve: timing is calculated
according to the conductivity distance measure by the set-point value set and the values set for the ON time (
Ton )
and the OFF time ( Toff ).
Timing is calculated as follows:

Read conductivity: 1%-65% of Set-point

E.v. ON = Ton ; E.v. OFF = Toff ;

Read conductivity: 65%-90% of Set-point

E.v. ON = 80% Ton ; E.v. OFF = Ton + Toff - 80% Ton ;

Read conductivity: 90%-110% (hysteresis) of Set-point

E.v. ON = 80% t.on , E.v. OFF = Ton + Toff -
80% Ton , if the conductivity value is nearing the Set-point range indicated; E.v. ON = 0 seconds (non-
active dosing) if the conductivity value is decreasing in the indicated range;
.
Fig. 10 - Operating diagram
Example:
Dosing liquid detergent
Conductivity Set-point = 10 units;
Conductivity read value = 7.2 units; (72% Set-point)
Effective Flow Rate = 4.2 l/h
Nominal Flow Rate = 4 l/h
The pump will dose 76% of the effective flow rate up to a value of 11 units, and will only start dosing again if the
measured conductivity value goes below 9 units (hysteresis around the Set-point value).
Dosing solid detergent
Conductivity Set-point = 9 units;
Conductivity read value = 6.9 units; (76% Set-point)
ON time = 20 sec;
OFF time = 10 sec;