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  1. The attached file shows how i have wired the PHTX 212 to the v200 18 e1b. This is, from what i can gather EXACTLY as shown in both the PHTX 212 and the 18 E1B's instruction manual. However i am still not getting any reading from MI2 (the input the transmitter is wired to). With a multimeter, i cannot find a signal on MI2, as if no power is running to that particular Input. I feel like I'm missing something very obvious indeed! Thanks in advance Memphis
  2. Joe- The pH sensor i picked up is from a garden centre, and as its a 'replacement' probe for an existing Bluelabs product. Cheap i know The product uses a BNC connection, just like the PHTX 212. Compatibility wise - could the probe only work with the Bluelabs product and not the PHTX 212? I will test the transmitter later and let you know how it goes.
  3. v290 200-18-E1B Transmitter: PHTX 212 (http://www.omega.com/manuals/manualpdf/M0447.pdf) Probe: Bluelabs 'Reaplcement' pH probe (http://www.planetnatural.com/wp-content/uploads/bluelab-ph-manual.pdf) I've been having a little trouble myself, trying to correctly wire in my pH transmitter to my v290 using Snap I/O v200 18 E1B I'm using Analog Input 2 for my pH transmitter, i have assigned it correctly in the ladder. However i don't seem to be getting any raw data from it what so ever. I've wired the transmitter EXACTLY as shows in the Omega spec sheet. (It is a two wire connection, problem?) I've used a mutlimeter, and placed the two probes into where the transmitter is wired to the 'Analog Input' part of the Snap I/O. And i get no electrical signal at all. This leads me to think that perhaps the internal circuitry of the Snap I/O may be faulty. Any help would be fantatsic!
  4. Hello Nogmor! Glad I could have been of assistance! I found this rather interesting, and i think it make be of some assistance to you. http://www.omega.co.uk/pptst/CL601_PHCL-602.html
  5. The company's router has a static IP which I've now located and entered the default gateway into the Card INIT FB I can now connect to the PLC through the company's LAN and sporadically through the internet. When i click 'Get OPLC iNFORMATION' (from outside the company's network), it retrieves the relevant info. That tells me that my logic at least can connect to the PLC. However, the connection doesn't seem to be stable, as two minutes after I've got the plc information, i get error message 210. (The usual Comm Error message). Thus, i cannot read any changing operand values, or use Remote Operator. Always found these forums to be most helpful! Learning networking and PLC programming all in one go!
  6. v290 Netgear DG834V3 Hello there! After the trials and tribulations of learning ladder logic to an acceptable degree, I have embarked on a journey into networking! What I aim to do, is to be able to use remote operator from any location with a internet connection. There didn't appear to be a webinar addressing this issue. The PLC is connected to a modem within a network My ethernet connection appears to be valid as i can ping the PLC from another computer on the network. I have forwarded port 20256 in the router config. So i gather that that means that I can access the PLC using Remote Operator as long as I'm within the company's network.. So my question is: What is required for for me to be able to connect to the PLC from the internet/outside the company network? Please let me know if there is any more information that you require I have attached my current ladder logic, please feel free to edit. Thanks in advance Memphis
  7. Thank you very much Joe and Simon! Always good to hear that you're going in the right direction. The pH only needs to be at the set point once everyday, and is then pumped out to another tank. Given that, i decided that over a period of 30/40 minutes prior to pumping, my current program should be able to account for any increases in pH. The acid or base that will be added to the tank can diffuse slowly so i don't want to end up with the program overdosing the acid and then trying to make up for it by adding large amounts of the base. Due to the fragile nature of pH electrodes, I've decided to place the probe externally to the tank. By pumping water from the tank to an external pipe and back, and then fitting the pH electrode so the part that takes the reading is inside the pipe, i can take more stable readings, as the water inside the 500 gallon tank is being constantly mixed by the pump. Hopefully this will decrease the time required for the mixing stage. I also hope this will help anyone looking for a basic pH management system, i looked on the forums for a while and couldn't find anything quite like this with attached ladder diagram. I'll be recieving the pH signal transmitter shortly and will let you know on the success or lack of it!
  8. Here is my current pH control subroutine: http://forum.unitronics.com/files/file/36-%7B%3F%7D/ I have linearised the input elsewhere in the program, and then averaged the input readings in order to prevent relay bounce and generally to insure a smoother running and to avoid and potential anomalys.
  9. 712 downloads

    pH control subroutine
  10. Hi v290 V200 18 E1B I am attempting to control the pH of a 500 gallon water tank.The pH needs to be at at 6.0 with a variant of .2. I was originally planning on using PID to control this, but i do not want the PID constantly be redosing. So instead have opted for a on/off diagram. he level of the water tank will alter as water is pumped out, once it has reached the required pH and once the daily drain pump starts As a result, the coding will need to be able to compensate for any drop in water level to not over dose the tank. I was planning on using the this pressure transmitter http://uk.rs-online.com/web/p/pressure-sensors/7396774/ too measure the changing water levels. What i want the code to achieve: When time parameters are achieved (say between 4-5pm). and the pH is too high. I want to measure the tanks level, dose the tank accordingly , wait 10 minutes until acid has diffused, check pH and dose again if not at required point. If the ph is within range i want to skip the dosing step. If any one can help me out with the above steps that would be fantastic Please let me know if there is any other information that is needed Cheers Memphis
  11. Hi I've tried to control an intake fan and a extraction fan by using SET AND RESET Coils, controlled by a set point (saved as a HMI entry MI). I also included a timer subroutine to try and prevent relay bounce However the program does not reset the coil when the temperature lowers. This is the Fan section of the project (the 1st image), showing the 'SET' part of the ladder This is the 'RESET' net Both the set and reset ladders also have a touch controlled on/off switch represented by positive/negative transitional This image shows the timer net, that is meant to stop relay bounce It should i think in theory work, if there are any experienced coders that would like to take a look that would be marvellous Thanks Memphis
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