I am well versed with Wonderware software. You are correct on many accounts. Wonderware is incredibly powerful, flexible software. Unfortunately WonderWares greatest pitfall is its price. Wonderware licenses require yearly renewall. Development licenses start at 1500 dollars a year, and runtime licenses run around 800 dollars. Thats a YEARLY fee that must be paid for continued support. In 10 years it will cost you well over 15 grand to run a single Wonderware application if you also own a development license. The development license is what allows you to create programs.
Regarding Ladder logic. The Automation direct DL06 PLC which I'm using as the controller, is programmed entirely in Ladder Logic. I can also program PLC's in Function Block, and Structured text. But the DL06 is only capable of Ladder.
DIYer, The pumps are incredibly accurate. These pumps can be sized down to less than a milliliter per minute. Meaning that if you wanted, you could dose in tenths of a ml very EASILY. All peristaltic pumps have very uniform feed rates. The reservoir can be sized to whatever you like, and then a peristaltic pump can be matched to the size. The pumps I've spec'd out will be perfect for anything between 10 and 200 gallons. But pumps could be sized for thousands of gallons quite easily.
Initial nuting of a fresh reservoir is the easiest part. Take the needed mililiters of each nutrient divide it by the pumps mL per minute rating and you have a run time for initial dosing. NOW for the cooler part. I see your system is drain to waste, which means you mix a new batch of nutes each time you feed. My system is also designed for maintaining a reservoir that is constantly recycling the nutes. After each feeding cycle the controller measure the PH and EC, and then the Proportional Integral Derivative (PID) Loops activate the needed pumps to restore the reservoir to its set points. As long as the DC motors maintain speed ratios in accordance to the nutrient ratios, the reservoir will continue to maintain the exact 2:1 nutrient ratio that is required - minus any difference that the plants create through absorbtion, (I can only monitor total dissolved solids, theres no way for me to check N-P-K ratios). Essentially this means never again touching nutrients or ph chemicals, unless its to change a bulk bottle, which could take several months, if not longer. The Nutrient bottles will have mixers to maintain uniform consistency.
