Ridder Aqua CX300, User Manual

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Maximum control percentage of mixer valve 0 - 100 %
1 -> 99: The percentage of the total cycle time that the mixer valve may be actuated.
100: Maximum control percentage EC has no influence.
This setting limits the length of time that the mixer valve will be actuated, so
that a delay in the dosing system (e.g. due to a mixer tank) will not cause
fluctuations in EC control.
Adjusting the EC mixer valve
Set the EC setpoint for the valve group. Make sure the differentiation time is set
to 0;
Start an irrigation cycle using the valve group.
Monitor the trend of the measured EC (Control EC) in relation to the calculated
EC setpoint in the 'Activities' summary.
Calibrate the mixer valve as follows:
1. How to set the optimum gain:
Set the gain depending on the EC level that you want the irrigation water to
have:
EC 0-2 mS/cm: Set the gain to 200.
EC 1-6 mS/cm: Set the gain to 100.
EC control tends to function best when the differentiation time is disabled (set to
0).
2. If EC control is still too unstable, lower the value set for 'Maximum control
percentage of mixer valve'.
3.3.1.2.2 EC control with dosage valves
EC gain 0 - 1000
This sets the factor that determines how many seconds the dosage valves must be
actuated, when a difference arises between the calculated EC setpoint and the
measured control EC.
EC integration time 0 - 1000 sec.
0: The integration time is disabled.
1 -> 100 -> 300: The degree to which the controller will aim to achieve an equilibrium
in operating the EC dosage valves.
When there is no difference between the measured EC and calculated EC
setpoint, the integration time ensures that the correct quantities of fertilizers
are dosed.
Adjusting the EC with dosage valves
Set the EC setpoint for the valve group. Make sure that the gain is set to 30, and
the integration time is set to 100.
Start an irrigation cycle using the valve group.
Aqua CX300
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