Ver 5.6 IntelliDose Installation Guide (30 June 2020) Copyright© 2020 Autogrow Systems Ltd 6
One part or two-part dosing
For 1-part dosing, only one dosing pump is used to add nutrient to the mixing tank. When 2-
part dosing is selected then two dosing pumps will be used to add part A and part B stock
solutions. In this case it is sometimes found the part A and part B do not dose at exactly the
same rate (one tank empties quicker than the other). There are a number of reasons why this
may occur including different pipe arrangements, filters partly blocked, tanks or dosing valves
mounted at different heights and even the difference in specific densities of the stock
solutions. To compensate for this, you may adjust the two dose rates electronically by
reducing either A or B dose rates below 100%. For example, if you set A at 100% and B at 95%
then B will dose a little less than A each time that a dose is added to the tank. This is set by
trial -and-error starting with both A and B at 100%. (Always leave one at 100% and reduce the
other)
Multi-part dosing
With 3 to 9-part dosing, the ratios may be varied to suit a feeding schedule as recommended
by the nutrient supplier. In this case the ratios between all the nutrient parts can be
individually varied. A schedule may be added with IntelliGrow which will automatically vary
the nutrient ratios and EC as required. This can be used to gradually and automatically
change the mix from vegetative to generative whilst at the same time gradually changing
the EC. Note: On each date specified, the settings change to the new values and then stay
at these settings until the next date schedule is reached. Once the last entry is reached the
settings just stay at those values permanently. It is important to note, that when using
variable ratios for various nutrient parts, the dose time must be set to be long enough that
the part with smallest ratio still gets a dose of one second.
Sequential dosing (default ON)
This causes the dosing pumps or valves to activate in sequence, one after the other and
allows high current valves or pumps to be connected to the unit without fear of
overloading the controller or its power adapter. If in doubt about the current required to
drive the pumps, always select sequential dosing. If 3 or more nutrient parts are selected
sequential dosing is enforced to avoid damage to the controller.
Proportional dosing (default OFF)
This causes the dose size to automatically vary in proportion to the error, it is useful when
you want the tank to dose up quickly. If this is selected, then the dose size is specified as both
a maximum and minimum dose time. The controller then looks at the size of the error and if
large, will give large doses, as the EC or pH setpoint is approached, the controller will give
smaller doses. This is useful in irrigating (drip) systems that do not re-circulate as it allows
rapid dosing after each irrigation occurs. This feature is not available with more than a 2 part
mix.
