Application of Nano PLC In A Growroom

[BlazenCDN]

HMI over network useing a remote desktop app on my playbook

 

[Danks2005]

During my apprenticeship we learned about plc's, though I do not have much hands on experience with them, and it's been a while since I was in the classroom. I have pulled wire and terminated I/O cards, but there's not much to it when your just following a termination sheet. I still have my books and everything in the book is based off of the Allen Bradley SLC 500 series. I have a good understanding of hardwired automation and a strong grasp of ladder logic. I think I am going to start with 4 or 7 slot chassis and an SLC 500 or 5/03. I will start buying the parts when I harvest my current crop. Hopefully after my 2nd harvest I will have the PLC controlling the grow. Then start attemping to build an Interface, with remote accessability.

To start I will control:

lighting schedule for flower and veg room
veg room cooling
humidity
flower room cooling
E+F pumps

Then add:
CO2 control
Dosing of rez's
auto topoff
auto ph adjustment
Complete rez change
contant realtime monitoring of ph,tds, rez temp, room temp, humidity
high temp shut off
I'm sure I'll think of more

Feel free to suggest specific part #'s I may need/want and or suggestions of things I may want to control but am overlooking. I will post pics of my build as I go. I'm about 70 days from harvest, and will need this time for research to ensure I buy the proper hardware.

I love this thread, I have been talking about this for a year or more, and this thread gave me the motivation to retrieve my books and actually start reading and preparing and pricing controllers, chassis, and I/O cards.

Thanks!

 

[BlazenCDN]

You will need an analog input card for you ph, ec, and co2 sensors to do dosing, analog cards are not cheap so you will want to limit the amount of inputs you need, for the heating and cooling its cheaper to use thermostats and run the contact to a plc input for control.

I control my dehumidifier and fans, the inline blowers, the E & F pump for the babies, the ballast power, flip relays, PH up or down, nutrient ppm, CO2 PPM, Feed pump for the main system, and the chiller, and it keeps the RO water res and the main res topped off.

Nutrient and ppm is controlled according to the schedule on the HMI, realtime ph, ec, and co2 levels are displayed and charted on screen, Co2 levels can be changed on the HMI.

There are fault conditions programmed in for ph changeing to quickly, ph to high, ph to low, co2 low, co2 high, ppm low, ppm high, co2 bottle empty, RO res tank low, main res system low which also kills the pumps. I also have a reminder once a week to check my pump filters, when any of these faults occur the PC sends an email (or text message but i prefer email) to my phone with current ph, ec levels and the fault condition. It also automatically changes the water every 2 weeks.

Future additions:
Water sensors on the floor in every room to detect leaks.
Amperage monitoring on ballast circuits and controller supply.
R/H and temp probes and transmitters paired with process controllers or possibly analog input card for the plc.

Parts needed for mine:
3 water level sensors
12 relays of various load capacities
10 diaphragm valves (7 gravity feed suitable, 3 need pressure)
a ph and EC probe with transmitter (see below)
2 co2 sensors with transmitter built in
12VDC power supply
24VDC power supply
allen bradley micrologix 1500
analog input card
24VDC output card
lots of cords recepticles, terminal blocks, fuse holders, blah blah

Hannah industrial grade probes and transmitter
HI 3001 - Conductivity Probe w/NTC Sensor for ATC
HI 1001 - pH Electrode w/Double Teflon Junction & BNC
HI 98143-04 - pH & EC Transmitter with Isolated Output 0-4V

honeywell CO2 sensor - C7632A

 

[Danks2005]

You will need an analog input card for you ph, ec, and co2 sensors to do dosing, analog cards are not cheap so you will want to limit the amount of inputs you need, for the heating and cooling its cheaper to use thermostats and run the contact to a plc input for control.

I control my dehumidifier and fans, the inline blowers, the E & F pump for the babies, the ballast power, flip relays, PH up or down, nutrient ppm, CO2 PPM, Feed pump for the main system, and the chiller, and it keeps the RO water res and the main res topped off.

Nutrient and ppm is controlled according to the schedule on the HMI, realtime ph, ec, and co2 levels are displayed and charted on screen, Co2 levels can be changed on the HMI.

There are fault conditions programmed in for ph changeing to quickly, ph to high, ph to low, co2 low, co2 high, ppm low, ppm high, co2 bottle empty, RO res tank low, main res system low which also kills the pumps. I also have a reminder once a week to check my pump filters, when any of these faults occur the PC sends an email (or text message but i prefer email) to my phone with current ph, ec levels and the fault condition. It also automatically changes the water every 2 weeks.

Future additions:
Water sensors on the floor in every room to detect leaks.
Amperage monitoring on ballast circuits and controller supply.
R/H and temp probes and transmitters paired with process controllers or possibly analog input card for the plc.

Parts needed for mine:
3 water level sensors
12 relays of various load capacities
10 diaphragm valves (7 gravity feed suitable, 3 need pressure)
a ph and EC probe with transmitter (see below)
2 co2 sensors with transmitter built in
12VDC power supply
24VDC power supply
allen bradley micrologix 1500
analog input card
24VDC output card
lots of cords recepticles, terminal blocks, fuse holders, blah blah

Hannah industrial grade probes and transmitter
HI 3001 - Conductivity Probe w/NTC Sensor for ATC
HI 1001 - pH Electrode w/Double Teflon Junction & BNC
HI 98143-04 - pH & EC Transmitter with Isolated Output 0-4V

honeywell CO2 sensor - C7632A

Very nice setup! I may be asking you some questions in the weeks/months to come.

 

[BlazenCDN]

Ask away, happy to help. Mine is an ongoing project that is never done, there is always more to add. I first started using that micrologix controller about a year ago, its worth all the time spent building and programming, a PLC does a better job of keeping everything in spec then I ever did, and it frees up a lot of time.

 

[high life 45]

Very impressive blazen!

How much did your set up cost? Immjust looking for a ballpark figure.

 

[BlazenCDN]

Industrial grade shit is mad pricey but I managed to do this on the cheap over time, when I started out my budget was $1500 and I used a bunch of spare stuff from work so I didn't pay for the PLC or I/O cards, power supplies, relays, or most of the wire so thats like $4000 right there, but you can probably find this stuff used on ebay. I ended up spending about $2000 in the end on sensors, valves and hardware and stuff. Now i gotta buy a cabinet and rebuild it all too code which i imagine will probably run me up another $1500, I used scrap wire and just used the wrong colours when I ran out so its kind of a mess although free wire is dope because that shit is expensive. I run 2x2400watt rooms in DWC when i built these 2 rooms a few years ago I spent $12000. Im in Canada by the way eh so if your in the US everything is cheaper damnit.

 

[high life 45]

ok so this is semi costly investment......

seems like my best bet would be to befriend someone in the industry and try to get things cheaper

I am really interested, any books that you recommend that might give me a good start?

 

[BlazenCDN]

Yeah it is costly but you said it right its an investment, think about the benefits to your yield from having everything precisely controlled 24/7. I have been growing in this space for a while but I'm just starting my third run since finishing the automation(its never really finished) and I have seen a big improvement I would say about 35-40% but that may just be mostly because of my own personal situation since I am so busy with work it was hard to give the plants the attention they need. I used easily 3 times the amount of nutrients I used before and double the co2(I use tanks).

Having a friend in industry would be ideal haha especially if that friend can help set it up, its not for the average user and this equipment is generally not user friendly.

As far as books I am not sure, allen bradley plc programming software like rslogix5/500, contrologix has good explanations in the help guide but you would need the basic knowledge. For complete grow space control like I set up the programming is simple enough there is no complex logic just a bunch of simple conditions, but for a amateur with no plc programming experience it would probably be tough. Now of course I wrote a program already for my own application so if someone out there has PLC there trying to program
I could probably be convinced to share the logic and that would make things a lot easier even if your own application is unique you could use it as a guide.

 

[LilMissPuffIt]

This is a very cool thread!

 

[Rednick]

I could be wrong but don't digital ballast have "soft start" control built in to ramp up power when igniting? I am not sure if the ballast would stand up to the amperage surge when you flip to cold bulbs. I know someone who does flip without powering down but he uses magnetic ballasts. PLC would be the best way to do it because everything would be very accurately synchronized. If you dont have experience working with PLC's you could just use a relay. You run the power for your ballasts through a relay on normally closed contacts and use a cycle timer to power the coil for 5 minutes or whatever while you do your flip, just make sure your timers stay in sync.

My understanding, so far, is that SSRs work for digital because of the soft start gently ramping up power not as big of a surge. DPDT contactors for magnetic (240v). Flipping without powering down causes arcing, reducing the life of the contactors.

 

[Biosynthesis]

Uh.... this is all way over my head but fantastic sophistication. Please come set me up a grow room. Cheers!