Total Hydroponic Control (T.H.C.) - The build starts NOW!

Hello Rollitup, its been a while since I was last here, and consequently, this is a new account. I've been through 5 indoor grows, and 3 outdoor grow seasons. I will start out by saying, that when it comes to growing cannabis I am clearly an amateur. However, I've been working with automation for over 5 years. I am currently employed by a fortune 500 company, and when I wake up everyday I head to work to argue with high speed manufacturing, and process control systems. I'm familiar with Allen Bradley, Automation Direct, Koyo, Omron, Gidding & Lewis, and G.E. PLC's. I eat, breathe, and sleep, automation.

Lately I've been very intrigued with the D.I.Y. automation here on Rollitup. It is clear that RIU is a community of intelligent, driven individuals who are more than willing to share their knowledge and expertise. I applaud all of you who are continually striving to add integrity, knowledge, and ingenuity to the world of marijuana.

This thread is to be my opportunity to share my knowledge on growing, in the manner I am most capable of: Automation.

While many of you have undertaken Arduino projects, with great success, I will be developing a grow system centered around proven industrial process control equipment. I love the arduino platform for hobby projects, and it certainly is a great fit for growers without a significant budget. I will explain in detail why i have made each of the equipment choices I've made, in the hopes that you the reader will understand why even though the price seems significant, the benefits counteract the initial investment.

The goal of the system is complete and total automation. What does that mean? Watering, feeding, lighting control, temperature control, humidity control, co2 control, ph control, and security. If marijuana was grown by multi billion dollar corporation, inside giant facilities, their systems would look and operate strikingly similar to what I intend to build, just on a much larger scale than my project. My grow system will be industrial hardened, capable of withstanding harsh environments and demanding situations. This entire thread will encompass the automation, instead of the growing. A grow journal will follow the completion of the project.

Lets start with a system summary. Including a budget. The budget for this project is 5 thousand dollars. Don't cringe, we have a lot to accomplish!

Equipment summary
PLC - The brain of the operation.
HMI - Human machine interface, a touch screen which allows user manipulation, for changing timers, PID loops settings, schedules, etc etc. The HMI talks directly to the PLC.
EC/ PH transmitter - This device sends information to the plc regarding current ph, and current conductivity.
co2 transmitter - this device sends information the the plc regarding the co2 levels at the sensor
temp/humidity transmitter - this device sends information regarding the temperature and humidity of the environment back to the PLC controller
Relays - to control the flow of power to devices
Liquid level sensors - to monitor reservoir heights
solenoid valves - to control water flow to the reservoir/hydroponic system.
Miscellaneous control wiring to the various remote devices
peristaltic pumps - to dose nutrients into the reservoir

I will go into more specifics of the project in a short while. But until those post start happening. I should probably leave you with a teaser to prove this project is happening, even as we speak...

Pictures are worth how many thousands of words? I'll try to do a little explaining with each picture....

This is an HMI. Its a 6 in Automation Direct touch screen interface. It retails for 699.00$ USD. Its ethernet capable, which means a user can connect the system to their home network and monitor the operator screens from anywhere in the world. It will display all current environmental levels, and allow for the input of schedules and desired levels. It has a built in html server which means you can custom design an accompanying website which loads much the same way a user logs in to control settings. It can send email alerts on any system variable. For instance if the ph drifts out of a range you will get an email letting you know, if the temperature exceeds a safety limit and the controller shuts the system down to prevent damage, it will send you an email to let you know. All screens, and the system itself can be password protected to multiple user levels.

This is belden signal cable. When it comes to transmitters, and sending analog data, belden is the way to go. This is a 100' reel of 22 gauge 3 twisted, and shielded pair. I will be using it to transmit the analog signals from the ph/ec transmitter back to the plc. The foil shield and twisting of this signal pairs is what makes this cable so unique, and capable in an industrial setting, together these two features help to eliminate, RF, EMI, and other common mode disturbances, which can cause anomalies in any electrical system. All signals will be 4-20 mA signals. There are several industry standard control signals, the primary two being +-0-10v, and +-0-20 mA. I exclusively use 4-20 mA because of its resilience to electrical noise. My main concern with electronics in a grow room is electrical noise from digital ballasts. Proper grounding, and bonding, along with an aggressive noise control plan is key to preventing stray signals from negatively impacting your process. This is one of the reasons I cringe when I review arduino projects. Most arduino applications utilize voltage signals, including 0-1, 0-5vdc. These systems are incredibly susceptible to electrical noise. Because a 4-20mA loop relies on current, instead of voltage, there is a certain degree of inherent noise immunity. Retail 107$

This is belden 2 pair twisted shielded cable, 100 ft. Retail 54$

This is two nema 12 enclosures, one will house the PLC and HMI, the other will contain the ph/ec transmitter. A nema 12 enclosure is rated for dust, debris, and splash environments. Going to a nema 4x enclosure would also make them wash down rated, meaning you could literally take a garden hose to your grow controller. I don't plan on watering my controller, just the plants, but in a worst case scenario all of this equipment is splash rated, including the touch screen hmi. A third enclosure as large as the first will contain the outlets, and relays for controlling external devices, such as air conditioners, pumps, ballasts, etc. the 16x12x8 enclosures were bought for 79$ each, the 8x6x4 enclosure was purchased for 54$

Simple enough: PH/EC calibration, cleaning, storage solutions. If you have a digital meter you've used these before. Made by Hanna Instruments.

This is the ph/ec transmitter. It sends back 2 analog signals to the PLC controller. Both signals are 4-20 mA. Example: If the ph of the solution is 14, the ph signal is at 20mA, if the ph is at 2, the signal is 0 mA. This controller has galvanically isolated outputs to mitigate possible sources of noise back to the controller. The ph and ec probe are separate units. This transmitter retails for 400$ Made by Hanna Instruments.


This is the EC probe, it sends an un amplified signal back to the ph/ec transmitter, which then processes that signal, and scales it to the output range. This probe retails for 130$. It should never need replacement. Made by Hanna Instruments.

This is the PH sensor. It also send an unamplified signal back to the transmitter, which does all of the scaling before sending back a processed signal to the PLC. This probe retails for 125$. It should be replaced, like almost all probes, once a year. Especially since it will be submersed and measuring the ph 24 hours a day. Also made by Hanna Instruments.

Relays, and Relay bases. For controlling the flow of electricity to the external devices. 100$ in miscellaneous wiring supplies. Automation direct.


Terminal blocks, to make wiring less cluttered and more organized. Automation Direct.

Relative humidity and temperature transmitter. It will send back 2 separate analog signals to the plc in the form of 4-20mA loops. Its measuring range is from 0-100 percent relative humidity, and -32 - 140 degrees Celsius. This transmitter is made by OMEGA engineering, it retails for 175$

The BRAINS of the beast. This is a koyo/direct automation, DL06 PLC. It is capable in executing over a thousand boolean arguments in under a millisecond. It can control up to 8 P.I.D. Loops. It has expansion for up to 4 expansion cards. Slot one is occupied by an analog input module, this module can accept up to 8 different analog inputs, all 4-20 milliamp range. We have 1. Temp 2. Humidity 3. Ph 4. EC. 5. C02.. A total of 5 analog inputs. This controller is programmed with Directsoft programming software. The software bundle which includes all features retails for 495$. It can program any of the direct automation line of PLC's, including the DL05, DL06, DL205 series, DL305 Series, and DL405 hardware series. The Analog input card retails for 130$, and the DL06 PLC retails for only 239$... Even though the PLC is in charge of everything, it actually carries a very small part of the project budget. These controllers are VERY reasonably priced. So a total for the PLC including software and cards comes to 864$, add an analog output card for control of the dosing pumps and we round it to 1000$




Questions and comments are welcome. In fact, they will drive the direction, and detail of this thread. I will continue to update the thread with the status of the overall project as I move through all of the developmental stages, up until the point its controlling a grow room. I will answer as many questions as I can. Thanks for checking it out, and I hope that someone can take something away from my experiences to improve their own. Cheers!

Wow this looks like it could be amazing! With all that technology you could hone nutrients and environmental aspects to a T. Subbed

Hey man, nice bunch of expensive looking toys you got there I'm all about automation, i always say i would rather man the machine then be it.

I'm most interested in the peristaltic pumps to dose nutrients into the reservoir, or more so how you intend to rig that up? I recently started a DIY to gravity dose my res, went with a liquid level controller and some solenoids only, whole thing cost me around $130 and i'm about done with it, here. How do you plan to have adjustability in the amount you dose? I couldn't figure out a convenient way with pumps, so i went with syringes in my build.
subbed.

That's an amazing idea, well thought out too. Something like that would come in handy for a large scale grow. You should look into marketing this.

DIYer, I was lurking in your thread earlier, and I couldn't help but admire the great lengths you've gone to in order to feed your plants without much human intervention.

I chose peristaltic pumps for a number of reasons.

Firstly they are incredibly consistent and accurate when it comes to pumping a specific volume in a given amount of time.
They generate positive displacement and require no priming. Because of this your not at the mercy of gravity, these pumps can generate enough vacuum to actually LIFT nutrients from bulk bottles.

The solutions being pumped never actually touch the pump! Only the tubing its being pumped through. The non contact feature of peristaltic pumps is incredibly important for PH chemicals. All of my pumps will utilize silicone tubing which is known for its resistance to chemical corrosion.

I plan to run two part Lucas formula and a PH up and PH down. Which will require a total of four pumps. The two pumps controlling nutrients will be a little more special than the PH pumps. With PH I'm not so concerned with volume, just the PH... But with the nutrients its critical that I hold a constant ratio between part a, and part b. This will be accomplished by coupling the pumps to variable speed motors. The motors speed will be set by the plc and will directly reflect a nutrient ratio. With Lucas formula its one part micro, to two parts flower, which makes for an easy solution to the problem, one pump will run at full speed while the other runs at 50% speed. Any ratio could be accomplished.

Nice equipment. Do you plan on using ladder logic with your PLC or are you planning on writing some code? Wonderware has a nice development platform you should check out if you haven't heard of it - that's what I originally wanted to do but opt out for creating my own software and code for the arduino, cheaper, but not exactly industry standard. The Wonderware software is great for ladder logic and setting up man-machine interfaces for on the PC.

http://global.wonderware.com/EN/Pages/WonderwareDevelopmentStudio.aspx



[video=youtube_share;GszmxAv3VKA]http://youtu.be/GszmxAv3VKA[/video]

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.

Total.Hydroponic.Control said:

(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.

Click to expand...

hmmm,... if you can't check N-P-K ratios, just TDS, i don't see how you're ever going to be able to give your plants the right ratios after your initial res mix. Why go that far with a system, and not run DTW? If you recirculate, you're never going to know your plants don't like a lot of one chemical, from one of your 2 bottles, and you'll just keep adding more back, causing lock out. My HPA DTW system uses less then 1.6 gallons of water a day, to water 6 full grown flowering moms. Little .2 second pulses of 50 micron mist ever 90 seconds is whats hitting my roots, very little runs off, would seem silly to toss it back in my res and have it muck up my ratio. In my setup i'll only ever have to fill a bulk bottle too, and i'm mixing mine with air bubbles, which if they say to shake it before use have to be ok.

I have run recirculating systems before, and reservoir changes once ever two weeks has worked incredibly well for me. I've never experienced a situation where after two weeks the nutrients had fallen so far out of range that it was causing plant stress. I'm more concerned with maintaining a target TDS/EC than maintaining the NPK ratios. The whole idea behind the nutrient ratios in the first place is that its been established that the plant uses those nutrients in a uniform manner, congruent with the schedule. I grow using aero, and no media. The roots hang in a chamber exposed to oxygen between feeding intervals (1 minute on, 5 minutes off), so i have no choice other than re-circulation being there is no media to store water/nutes.

The reservoir changes will be automated too.. drain and fill, so the only time I'll be touching the res is during a cleaning.

So let me get this right,.. you're going to automate the holy ever living hell out of all this grow,... and still change your own res every 2 weeks? Seems silly to me when you can just not over saturate the roots in the first place, and let your runoff go down the drain, i bet it will be way less then you toss every two weeks. Again, i hope you go with a small res in this setup.

An ultra sonic sensor will monitor the resivour level to the accuracy of an 1/8th inch. The reservoir will go through a drain/rinse/fill sequence once every two weeks. in between the automated reservoir change sequence the reservoir ph and EC will be maintained by PID loop. The reservoir size has yet to be determined... and it doesn't need to be, the PID's can be adjusted for any reservoir size.

I don't really like wasting water either... so the waste water will be pumped up to my rain water collection barrel outside the house, to be used for the lawn, and vegetable garden. I refuse to grow with any medium, I am stuck on aero.

TotalControl, really sick setup - can't wait to see this work out

Ignore any trolls - you know when you come in here talking about the initial startup costs a lot of people who can't afford it are going to hate on you

Best of luck.

Understood THC, but that setup will waste more water then drain to waste, everything does. It seems if this system were ever done on the scale its really intended for, DTW would be the only sensical thing to do. For the environment, and your wallet. You paid for those chemicals you'll be pouring away every two weeks.

EDIT
Get over yourself bobby, you're the only troll here. No ones talking about the cost, and you're also the only dumbass assuming what others can and can't afford. This is obviously meant for a large scale op, even if it's initially setup on a small scale, no sense in not doing how it would be done on a large scale IMO. If you're just building it to build it, like the guy making the robot to tend his plants, go for it. But if you intend to market it, you might has well make it make as much sense for the type of buyers that will be interested. No one is doing this on a super big scale and dumping res's.

Hey Bob . I don't think DIYer is hating at all. He makes a lot of very relevant points. Most of those points I have already considered the pro's and con's. This really will be an entirely hands off system, and even though a circulating reservoir will be involved, I promise right now, that it will only be touched for cleaning. Reservoir changes will be handled by the controller. I've done the whole reservoir change thing, and its not for me. DTW would be ideal, but my growing method of choice prevents it. Thanks for checking it out!

DIYer... I have to completely agree with you... If this system was controlling 20 kilowatts worth of lighting, DTW would be the only way to go. Thankfully this system can be configured any way you want. Drain to waste would actually be an easier setup from a programming stand point. In fact, to honor your input and logical arguments, I will include a setup page which gives the user a choice between drain to waste, and recirculation.

A system like this would be tits along with a 'growing method of choice' that mirrors the efficiency of the system. You should look into High Pressure Aero. It's a hell of a lot to digest at first, and it'll take awhile to dial in just right, but if you're just doing what amounts to soakponics now anyway, you wont do worse right out of the gate, and very little water will you waste just 2 cents,.. not trolling,.. LIKE BOB,.. lol

Here is the touch screens home page. Blue boxes are displays. Orange Boxes are Screen changes, and A color yet to be determine will be user inputs.