Omron Memory areas (new to PLC's)

[nikos 0]

Hello, Have gotten back on an Omron project I looked at a while back. Hydroponic greenhouse control. I posted once regarding "hello world comms with Omron" Have the following hardware CQM1H/CPU51, 4x Inputs(slot2), Builti-n 16 input,AD401 power supply and AD 401, and 4x OC222 modules, and OD213 (don't know what this one is used for). Sparse documentation on anything, and the system is controlled by a CX program running on a PC, that we need to get rid-of as we don't have the source and cannot support it. I need help in addressing all my inputs and outputs to use with an OPC server I believe that in the first module above (4xinputs), sorry there’s no number on it is connected some sensors such as Ph, Electrical conductivity, tank level, Temperature. In the AD401 we have Light CO2 and Temperature A whole slew of relays are connected to the 4x OC222 relay boards Am taking peoples here advice and have setup an OPC server. Have an OPC client SDX that I can talk to the OPC server running a demo. I now need to define the Omron PLC data in the OPC server, and need to give it the addresses that I’m interested in reading and writing… This is where my problem is, as I have no idea where my inputs and outputs reside in the plc’s address space. I have used CX programmer to connect to the PLC and download it’s “program” into CX programmer. Cant really understand the ladder logic that’s drawn (it’s been 25 years since I’ve seen RLL). Have used the memory reporting in CX programmer to give a “Usage overview” for the different memory areas, AR, DM etc.. So, does this help me in figuring out where my inputs and outputs live in the memory area, if it does, I cant see it... For example, how do I read the Ph input in that first add-on module, or how do I read the temperature in the ad401, and lastly, how do I toggle one of the relays in the OC222 modules Summarising, how can I figure out the memory areas my stuff is connected to and defined them in the OPC server. (Kepware) Sincerely, Nikos Sorry about the long post

[nikos 0]

FWIW, the link below is the cx programmer file I generated... http://193.218.36.79:9000/IUNG/hydro2_w_serial.cxp regards, nikos

[sobejon 0]

Hi, I'm a little confused at the layout you described but... attached is the CQM1H manual. in section 2 it will tell you about the "inner boards" (ones attached inside the CPU chassis) and section 3 ought to cover the rest. Good luck. i see your code does not have any symbols created... Cheers, Jon W364-E1-2.pdf

[sobejon 0]

the OD213 is a transistor output module. (sorry, I meant to add that to the previous post)

[nikos 0]

Thanx for the link. Using this I understand that many of the inner boards have specific memory areas that are used. One board is the MAB42 A/D board, so my first input (Ph) is connected to ch1, and its value is in IR232, and my second, Ec (electrical conductivity), ch2 should be at IR23 etc. What software in CX1 can I use to read these? CX programmer? CX supervisor? I tried to use DDE manager to create a point and paste it into excel, but It did not look like a value... I guess, ultimately I want to create points/tags in OPC Kepware server and read them from an OPC client... regards, nikos

[BobB 58]

I have semi automated several green houses using a CJ2M, wireless Ethernet and Citect. I also purchased some temperature and humidity sensors that go into the PLC. I also have a fogger to increase humidity (does not leave spots on the leaves for fungus to grow), variable speed controllers for fans etcetera. I grow orchids - one green house is running at 75% humidity, one at 70% and several others at 65%. I trend the temperature and humidity in Citect and am about to add a watering system to the overall project. I also have several tanks set up with fertiser in them in a solution and am just about to automate the fertiliser system. The tanks have small stirrer motors to keep the whole thing moving. Also considering an automated insecticide and fungicide regime. I would like to have some EC, Ph and moisture sensors as well but these would be way too expensive - 8000 odd orchids! Wish I had more money and time as I am sure there would be a huge market out there for something like this. Too hard for me in a CQM PLC - need more horsepower, communications etcetera. What are you using for Ph and EC? Something inexpensive? I would probably require to measure these in at least 100 places in the green houses. I refuse to use OPC at this point as most of my 'real' work projects require a far faster response than OPC can deliver. I normally use Omron Controller Link or Ethernet I/P. Controller Link is best but Ethernet I/P surfices most of the time.

[nikos 0]

Hi Bob, Pretty cool setup. Are you doing this "soiless"? We have temp and Rh wind inputs as well as foggers, boilers, and window/curtain control.... The main purpose of the system though is to "mix-up" various nutrient recipes depending on specific "recipes". There are 12 peristaltic pumps that dose these out, as well as one that uses dilute nitric acid to adjust the solutions Ph. After the solutions are mixed they are used for watering cycles programs at different times of the day, four green houses in all. The experiments are part of student research that eventually gets them an MS in horticulture. As an aside, one problem that is seen is that Ph is not very linear around ~5.8 or so where they want it, and here, a couple of drops more or less has a big influence on the resulting Ph. One thought I have is to use a much smaller capacity pump to tighten up the "hysterisis". The Ph meters are somewhere around 400 euro, but they do not really last more than several months before they need replacement. I've been told there are more accurate ones, but they are more expensive, and it seems most vendors only guarantee accuracy for only 3-6months... I have understood the above from the botanists and horticulturists that experiment with the system. I'm just an engineer that has been given the job to "improve" this system regards, nikos

[BobB 58]

I am doing it soiless but probably not as yoiu mean. My growing media is coco husk and perlite (sponge rock), sometimes added spaghnum moss, charcoal, zeolite etcetera. I guess you refer to hydroponic. I am consdering semi hydroponic for some orchid types but it does mean that orchids grown this way will have to grow a new root system to grow this way. It involves using the usual large peletts (15-18mm diameter) and a pot that is sealed in the bottom but has holes about 20mm up. This allows the addition of fertiliser solution and due to the size of the holes the pot fills up and then drains down to the hole level. One of the greatest problems with hydropnic growth is that the salts from the fertiliser build up, rots the roots and kills the plant. The semi hydroponic method flushes the concentrated salt solution from the pot with fresh stuff but still allows the migration of water/fertiliser upwards into the growing media via the hydroponic action. Mine is just a home setup that I am playing around with for myself because I can - also it may save me a lot of time - my most precious resource. Yours appears to be a commercial project - I have not been there and wish you good luck. I really have no more experiences at this stage to help. By the way, I would like to measure Ph in the pots with a probe - a number of pots in an area all with the same plants and one sensor - common media and re-potting at the same time may enable me to do this - I do not know at this stage. I would not use acid to adjust Ph for my setup but the various forms of lime (dolomite [calcium also here], and the other forms). I cannot, at this stage, see a method of automating this. Please also bear in my I have a hobby set up - it is constant - I am not trying to produce a commercially viable product such as lettuce for example. One of the things that is absolutely imperitive for what I am doing is 7-8% calcium in my fertiliser and low nitrogen. I use Peters CalMag finisher due to the high level of calcium, medium/low nitrogen, medium phosphorus (flowers) and good mix of trace elements. Commercial production of hydroponic lettuce for example would require probably require higher nitrogen and lower phosphorus as they are not trying to produce flowers but fast green growth and off to market in the shortest possible time to make a buck. Also hey do not keep the plants for any length of time but off to market in the shortest possible time.