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www.agrowtek.com
| 83 Ambrogio Dr Suite H Gurnee, IL 60031 | [email protected]
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pH Dosing
GC-Pro can monitor your pH levels and dose up and down buffer solutions to maintain automatic control of your nutrient pH.
The GC-Pro is designed to deliver volumetric doses with Agrowtek’s standard AgrowDose
TM
pumps. AgrowDose
TM
pumps are
durable peristaltic type pumps which deliver consistent doses from any size stock tank to your reservoir for reliable, low
maintenance dosing. Solenoid valves and other equipment can also be used on a timed basis if desired.
pH dosing works like nutrient dosing and is a very simple process. The controller monitors the pH reading and when it is
outside of your pH settings, it will initiate the dosing process either up or down as required. The dosing process starts with a
delay time; if the pH returns to within parameters before the delay time has elapsed, the dosing process will be terminated. If
the pH still needs correction after the delay time, the required pump will deliver the set milliliter dose. The process will then
repeat with the delay time between each dose until the pH reaches the set-point.
Day/Night pH Set Points: The desired pH for the controller to maintain during the day and night periods.
UP Dose: mL (or seconds) The dose amount that the UP dosing pump should deliver on each up-dosing cycle.
DOWN Dose: mL (or seconds) The dose amount that the DOWN dosing pump should deliver on each down-dosing cycle.
UP / DOWN Output #’s: The output numbers to assign to the respective up and down dosing pumps.
Dwell Time: The time to wait before dosing when pH needs correction and between each subsequent dosing cycle.
Note: The dwell time can be set to ‘0’ for continuous repeating dosing cycles.
Nutrient Dosing Interrupt
pH is often influenced by nutrient dosing and it may be desirable to have the system wait until the nutrient dosing is complete
before dosing pH; if this is the case, set the nutrient dosing interrupt to “On.” Otherwise, to allow pH dosing to occur
simultaneously with nutrient dosing, set the dosing interrupt to “Off.”
Cancel Output: Output to disable when pH dosing is active. Intended to disable the main feed pump when dosing if desired.
To disable this feature, leave the cancel output set to 0.
Dead Band: Drift allowed from set point before re-dosing back to set point.
Reverse Band: Drift allowed in opposite direction before dosing opposite pump back to set point.
If pH outside set range
Start Dose Cycle
Auto pH Dose Control
If Dosing
is Active
Disable Output
(feed pump, etc.)
Calculate Length of Time to run Dosing Pump
Injects dose amount (mL) each cycle.
Wait Dwell Time
Enable
pH Dosing
Dwell Time
Seconds
Pump Flow Rate
(system units)
pH
Reading
Cancel
Output #
Set-Points
Day & Night Values
Dead Band /
Reverse Band
pH UP Dose
mL per cycle
pH DOWN Dose
mL per cycle
UP/DOWN Pump
Output #’s
Run Dose Pump Output
If dosing still required
If interrupt enabled & nutrients dosing,
wait until nutrient dosing is complete.
Nutrient Dosing
Interrupt
