|
Simple, rugged doser with
optional PC interface The
new NutriDose1 is a simple, rugged hydroponic EC/pH doser.
The controller has a simple menu system that allows you to
set the nutrient EC and pH set point, calibrate the sensors and
set irrigation timings etc.
In its basic form it will automatically add nutrient stock
solutions and correct the pH of solution in a mixing tank.
It can also be used to periodically switch on an irrigation
pump for a drip irrigated or flood-drain system. An
optional PC interface may be added which will allow
the NutriDose to communicate with a PC running CompuGrow software.
This allows a PC, which can be up to 1200metres away, to
view readings, view and change settings, log data for viewing in
graphical format and sound alarms should anything go wrong.
The PC can even be set to call a telephone and even send a
text message to a GSM cell phone (if fitted with a GSM modem).
One PC can be connected to many controllers over a total
distance of up to 1200m (3000ft). Features:-
Dosing The NutriDose1 measures the nutrient strength in solution and whenever the reading falls below the set point it automatically operates pumps or solenoid valves to add more concentrated nutrient. The nutrient stock solutions can be one-part or, more usually, two-part (A & B). After adding a timed dose (user set), the controller waits for an interval (user set) to allow the added nutrient to thoroughly mix-in before checking to see if a further dose is required. The ratio between the A and B parts can be varied to ensure absolutely equal dosing. A
similar process is used for pH correction.
When dosing acid to lower the pH the controller will
automatically make allowance for the fact that EC dosing usually
lowers the pH in addition to raising the EC.
This avoids the tendency to overdose pH that some dosers
may have. Auxiliary
output - Irrigation An
auxiliary output is provided that may be used to periodically
switch on an irrigation pump to deliver water to a flood-drain
table or via drippers to a crop growing in media pots, bags or
slabs. The irrigation
duration is set by the user and the interval between irrigations
can be set to different values for day and night.
Alternatively, a solar sensor may be added to provide solar
integration triggering during the day.
By this means the interval between irrigations is
automatically adjusted to match the transpiration rate of the
crop. When a solar
integrator is used, the day intervals are set to the maximum
expected time and provide a fail-safe backup so that if a trigger
is not generated by the solar sensor, the timer will eventually
force an irrigation. Solar
integration avoids the media becoming saturated in cool/dull
weather and becoming too dry in hot/sunny conditions. Auxiliary
output – add water The controller can have two EC set points, one for day and one for night.
There are a number of theories that suggest altering the EC
between day and night can assist in reducing tip-burn in lettuce
and blossom-end-rot in tomatoes and capsicum.
One suggestion is that the EC is lowered during the day to
allow free transpiration whilst the other recommends lowing it at
night when calcium translocation is easiest. Whichever theory you
subscribe to, the NutriDose1 can automate the process. The
auxiliary output may be used to operate a two level mixing tank.
At the beginning of each day, (or each night) water is
automatically added to the mixing tank in order to dilute the EC
to the “low EC” set-point. This
low EC is maintained by the doser for the remainder of the time
period after which it switches to the higher EC setpoint.
Alarms There
are three possible alarms; one on the controller (buzzer plus
flashing light), another on the PC (if sound card fitted) and the
third by the PC dialling a remote telephone or cell phone (MODEM
required in PC). If a
GSM modem is fitted then the PC can send a text message to a GSM
cell phone. Each alarm
has a separate enable. Solar
Sensor(OPTIONAL) A
small solar sensor may be added which adds a number of features:- 1)
The NutriDose1 has a built-in solar integrator which is used for
irrigation triggering 2)
It automatically allows the basic NutriDose1 to determine the
period of the day when the sunshine is significant.
This is useful where a different EC for day and night is to
be used. 3)
Different irrigation periods for day and night may be required and
the light sensor allows the controller to automatically detect
dawn and dusk. When
ordering, specify the Autogrow “one wire” solar sensor. Environment
sensor (OPTIONAL) As
an alternative to the solar sensor above, a small environment
sensor may be connected. This allows the data-logging of air
temperature and relative humidity in addition to solar energy.
When ordering, specify the Autogrow “one wire”
enviro sensor with solar. PC
interface (OPTIONAL) A communications interface to a PC may be added by plugging a small module into the main circuit board inside the controller. This allows full communication to a PC running the CompuGrow software via a small interface box at the PC. The CompuGrow software allows all readings and settings to be viewed, settings to be changed and logged data to be viewed graphically. The logged data can include EC, pH, Nutrient temperature, solar energy, integrated solar and if an environment sensor is added, can also display air temperature and humidity. The PC interface also provides an enhanced alarm system to warn against anything going wrong. If an alarm occurs, it can be set to sound an alert through it’s speakers and also dial out to a remote telephone. Some of the following contacts are wholesale only but they will direct you to a local reseller USA:American Hydroponics www.amhydro.com
or phone 800.458.6543 (from overseas +1 707 822 5777) |
