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Autogrow
Systems Ltd
NutriDose II Computerized
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| Overview
The NutriDose II has higher power output than NutriDose1 and also has a PC interface. The PC provides data logging and subsequent graphical display of EC, pH and nutrient temperature as well as the ability to remotely set and trigger the controller. It provides remote alarms ie at the PC (via its sound card) and also telephone alarms (via its MODEM) to a pager or cellular phone. The NutriDose II also provides accurate monitoring and heating control of the nutrient (or grow bed). Last of all it has two extra outputs which can allow it to operate as a simple batched "to-waste" fertigation system or to remotely control events such as reservoir filling and dumping. When used for fertigation, the controller has an input which can be used to trigger an irrigation. This input can be triggered by a solar integrator signal such as that provided by the Autogrow TRS2000 Minder. This causes the controller to irrigate after set quantity of sunlight has been received The Compugrow software allows the user to trigger events from the PC such as (1) switch dosing ON/OFF, (2) start irrigation (3) fill tank (4) dump tank (5 ) Add water to main tank. Alternatively, these outputs can be used for any other purpose you wish such as remotely unlocking the access gate etc. By using remote access software, it is possible to dial into your PC from anywhere in the world and to view the readings, graphs and settings and to make any changes you wish. Of course this feature is password protected. A new feature of the doser is the two time zones. This permits different EC settings to be made for day-time and for night-time. Many growers will have a lower EC setting for the day time when the plants are transpiring and when afternoon arrives they will raise it back up to the night-time setting. The time zone change over points can set by the grower to achieved the exact effect desired. In addition, the remote control feature allows the NFT grower to add a predetermined quantity of water to the reservoir tank to rapidly lower either the EC or the temperature by a click of the mouse from office or home. Note that to achieve this level of control a relatively small quantity of nutrient is stored in a relatively large tank. This allows one or two batches of additional water to be added without overflowing. The small quantity of water also means that the plants, by their normal feeding, will reduce the EC sufficiently during the early morning in time for the mid-day sun. The other remote control feature available to NFT growers is the ability to dump the nutrient remotely. Alternatively this output could be used to unlock an access gateway, turn on/off lights, trigger fogging etc. Specification – NutriDose II On-Line The devices may be grouped into different systems. Usually a group will represent one greenhouse so that viewing is organised in a logical way. Data may be uploaded to the PC either every 1 or 5 minutes. This is set on the PC. Alarms may be set for each NutriDose and Minder and limits set for each measured variable. Settings EC set point PH set point EC dose time PH dose time PH raise or pH lower Dose interval Dosing ON/OFF Temperature set point EC, pH and Temperature alarm limits Alarm delay time Alarm ON/OFF Fill mix time (relay 1 ON time) Irrigate time (relay two ON time) Fill now command (relay 1 ON) Irrigate now command (relay 2 ON) EC, pH, Temperature Measurement EC resolution 0.1CF (0.01 mS/cm) pH resolution 0.01 pH Accuracy of EC and pH will depend on calibration If used in an electrically quiet area and properly calibrated at a temperature within 10 deg C of application temperature, accuracy will be better than +/- 0.2 Temperature resolution 0.1 Deg C Temperature accuracy better that 0.5 deg C without calibration, 0.2 deg C with Temperature in Deg C OR Deg F Conductivity in EC (mS/cm) or CF units Different day and night set points for EC Timed dosing for easy set-up Logs EC, pH, Temp to disk every 5 or 1 min Easily recalibrated Controller continues to operate if PC goes down Compugrow software operates under W95/W98/W2000 PC can be up to 1200m from controller Internal Power supply (either 120V or 230/240V) Two year warranty Easy to recalibrate in any standard solution. Calibrations (and settings)are stored in permanent memory (ie they are still there if the power fails) EC, pH, temperature Control EC control range from 0.00 to 9.99 mS/cm (00.0 to 99.9CF) PH control range from 2.00 to 9.99 pH For temperature control, the system works as a simple thermostat. If the measured temperature fall to one degree C or more below the set point, the heating output will come on. If the temperature rises to 0.1 degree above the set point the heater will go off. Two extra relay outputs are included in the controller. These may be used to implement either a simple batched fertigation system or else they may be used to implement some remote control functions from the PC (see below)
Irrigation control A tank is used to prepare a batch of irrigation water dosed with fertiliser and pH corrected. To do this the controller energizes a 24V AC "fill/mix" output for a user set time, which must be at least long enough to allow the tank to fill and for the dosing to complete. When a trigger signal from the solar integrator or timer is generated, the "irrigate" output is energized. This is used to switch on the irrigation pump. The time that this stays on for is set by the user. At the completion of the irrigation cycle the fill/mix output comes on again to refill and dose the tank. The tank is thus kept full to avoid ground water from pushing the tank out of the ground (assuming the tank is below ground level) Controls: Irrigate time 0 to 99 minutes Using the relay outputs for remote
control Output summary 24V AC - pH Lower 24V AC - pH Raise Contact closure - Alarm plus built-in buzzer 24V AC - Relay 1 (Fill/Mix) 24V AC - Relay 2 (Pump) 24V AC - Heater Input Summary Irrigation trigger from built-in solar integrator (needs enviro sensor with solar to operate) EC probe - 3 wires Temperature probe - 3 wires PH electrode - BNC connector – standard pH electrode (pH7 zero) Off-line operation Warranty pH electrodes carry only a 6 month warranty from their manufacturer. The Autogrow warranty specifically excludes any parts that have been broken or damaged by water, chemical attack or excessive temperature. In particular, the controller and PC interface must be stored and used in a dry, shaded and well ventilated situation. At no time must the case temperature be allowed to exceed 60 deg C (140 deg F). This warranty specifically excludes liability for consequential damages or for charges for labour or other expense in making repairs or adjustments, or loss of time or inconvenience. With any automatic equipment we always recommend an independent alarm system for maximum peace-of-mind. A few applications sheets follow:- 1) Single or two-zone batched irrigation system
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